science exam review

8/6/2019 Science Exam Review

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By: Vinny 1

Science Exam Review

1. Chemistry

Physical and Chemical Properties and Changes

Chemical Change: a combination of 2 or more elements to produce a new compound. E.g. Mg + O2

Mg O (Magnesium Oxide)

Physical Change: a change in state or form, but no new substance is created. E.g. state changes;

magnesium dissolves

Clues for Chemical Changes

y Colour change

y New gas

y New solid- precipitate y Heat produced

y Light produced

y Hard to reverse

Periodic Table

y Metals left side, non-metalsright side, metalloids along staircase

y Alkali metals(column 1), Alkaline earth (column 2), Halogens (column 17), Noble gases

(column 18)

y Columns ² same # of ´eµ in outer orbits

y Periods- rows- # of orbits

y Room temperature: black (solid), blue (liquid), red (gases)

I ons and Chemical Reactions

y Ion [giving away or receiving ´eµ (-)]charged atom

y Giving away electrons (+) ion

y Receive electrons (-) ion

y Example:

Li + O

y Other examples include:

o Mg + N= Mg 3N2

o B + F= BF3



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Atoms and I ons

y ions are charged atoms

y they become positive (+) by losing electrons

y become negative (-) by gaining electrons

y cation: positively charged ion

y anion: negatively charged ion

I onic Compounds

y The transfer of electrons from a metal to a non-metal (left side to right side of periodic table)

y formation of the positive and negative ions form a compound

y dissolve in water- separate ions

y conduct electricity

y form ionic bond

M olecular Compounds

y composed of non-metals (right side of periodic table) ² no metals in them

y form a covalent compound

y don·t transfer electrons

y share electrons- no exchange

y don·t conduct electricity ² no ions

y use prefixes like ¶di· and ¶mono·

y fuels (hydrocarbons)

p carbon- hydrogen compounds

p methane CH4

N aming I onic Compounds (no prefixes)

y each column of elements has a charge to become stable p E.g., Column 1 all have a 1+ charge

p Column 17 all have a 1- charge

y write the symbols, put the ionic charge above the symbol

p 1+ 2-

Na O

y criss-cross valences

p Na2O

y Charges add up to zero- the charges disappear

y ide- ending for 2 elements joined together

p E.g., oxide y ate for 3 or more elements joined together

p E.g., Sodium sulphate oxygen (sodium + sulphur + oxygen)

N aming M olecular Compounds (no criss-crossing)

y when naming use prefixes

p PCl3 phosphorous trichloride

y Never use mono for the first element



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y Examples:

p H2O ² dihydrogen monoxide

p CCl4 ² Carbon tetrachloride

p PF5 ² Phosphorus pentaflouride

Polyatomic I onsy groups of atoms

p E.g., OH, SO4

y behaves as if it is a single element

y single overall charge for both

p E.g., OH1-

y most end in ´ateµ

y Examples:

p Nitrate ² NO3 1-

p Chlorate ²ClO3 2-

p Carbonate ² CO32- p Hydroxide ² OH1-

y Y ou name them the same way you name Ionic compounds (with the crisscross)

M olecular compounds and Fossil Fuels

y fossil fuels is a another source of different molecular compounds

y coal, oil and natural gas are the most common fossil fuels

y these take millions of years to form from the partially decayed remains of ancient plants and

animals

y fossil fuels are called non-renewable resource because they are not formed as quickly as we

are using them

y when we burn fossil fuels, the energy stored within them heats our homes, powers our

vehicles and can be harnessed to generate electricity

y compounds extracted from fossil fuels are processed into petrochemicals

y we use petrochemicals to make consumer products and industrial chemicals, including

plastics, pharmaceuticals, and synthetic fabrics

y There are so many uses for molecular compounds here are some:

Crude oil and natural gas are then raw materials for a vast range of chemical products.

p Natural Gas Processing

o fuels and other products (helium and natural gas)

o gases (methane, ethane, propane, butane)

p Oil Refinery o Gases and liquids

o fuels (gasoline, kerosene, jet fuel, heating oils)

o Lubricants and other products (greases, waxes, solvents, asphalt, sulphur)

p Petrochemical Plant

o agriculture (fertilizers, pesticides, herbicides)

o detergents

o synthetic fibres



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o inorganic chemicals (sulphuric acid, ammonia, nitric acid)

o organic chemicals

o other products (paints, varnishes, solvents, adhesives, explosives)

o plastics

o rubber

y Molecular compounds can be harmful when they are leaked for example the toxin trichloroethene.

y this is a great problem in Canada because it goes into the ground and contaminates the

ground water

y but Dr. Edwards from the University of Toronto has discovered that pollutants are food for

microbes

y so they use microbes to remove trichloroethene from soil

y the microbes convert the pollutant into ethane (relatively harmless gas)

y now this method is being used around the world

W ord and Chemical Equations

y Chemical reaction: a process in which substances interact, causing the formation of new

substances with new properties

y Word Equations: a way of describing a chemical reaction using the names of the reactants

and products

y chemical equation: a way of describing a chemical reaction using the chemical formulas of

the reactants and products

y reactant: a chemical, present at the start of a chemical reaction, that is used up during the

reaction

y product: a chemical that is produced during a chemical reaction

y Chemical reactions can either absorb or release energy

y In the reaction below more energy is released than is absorbed. The word ´energyµ is therefore written on the right side of the equation, with the products

y if energy is absorbed then it is written with the reactants

y Diagram explanation:

Reactants Y ields Products

Law of Conservation of M ass (RE AD P AG ES 230-231)

y In any given chemical reaction, the total mass of the reactants equals the total mass of the

products.

y Remember mass is neither created or destroyed in a chemical reaction

Balancing Equations

Rules of writing and balancing equations

Word Equation: iron + sulphur iron (II) sulphide + energy

Chemical Equation: Fe + S FeS + energy



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o Example:

CO2 C + O2

3. Single Displacement- it begins with a element + compound and equals a compound +

element

A + CD AD + C

4. Double Displacement-it begins with a compound + compound and ends with a different

compound + compound

AB + CD AD + CB

5. Combustion

o Combustion is a chemical reaction in which a fuel ´burnsµ or reacts quickly with

oxygen

o products of this reaction are usually an oxide and energy

o Example:

Propane C3H8

o Complete combustion is a combustion reaction of hydrocarbons that uses all the

available fuel and produces only carbon dioxide, water, and energy ; it occurs when

the supply of oxygen is plentiful

o If the oxygen supply is limited, incomplete combustion may occur, releasing carbon

monoxide das and carbon (soot), in addition to carbon dioxide and water. An orange,

flickering flame often indicates incomplete combustion.

Corrosion

y This is the breakdown of a metal as a result of chemical reactions with its environment

Beneficial Corrosion

y corrosion of metal can be beneficial for example, when aluminum is exposed to air, it quickly

corrodes to form aluminum oxide (one of the hardest substances known)

y Aluminum oxide tightly coats the underlying aluminum metal, preventing any further

corrosion from occurring. This explain whys aluminum camping pans can be safely left

outside in the rain, while cast iron pan rusts in matter of days

Compound Element -

Metal

o Metals kick out metals

o non-metals kick out non-metals



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Rust

y reddish-brown flaky material produced when metals containing iron corrode

y rust does not stick well to the underlying steel (unlike aluminum and copper)

y Rust is a very porous and readily flakes away from the surface of steel. As it does, fresh steel

is exposed to further corrosion y this process continues until the steel is completely corroded

y there are many causes for rust such as: the presence of air, water, and electrolytes, along

with acidity and mechanical stress

y steel will not corrode if it is kept away from the water and oxygen which is why it lasts much

longer in dry climates

y salt does not cause corrosion of iron but it speeds it up once it starts (it is an electrolyte that

helps the rusting process)

y Y ou can prevent corrosion by using corrosion-resistant material, protective coatings, and

galvanizing

y A simple way to prevent corrosion is to cover the metal with a rust-inhibiting paint, chrome, or

plastic coating but if the coating is chipped of scratched corrosion is inevitable

y Using corrosion-resistant materials is a great way to prevent corrosion. For example, most

cutlery is made from stainless steel, an alloy of various elements, including iron, carbon,

nickel, and chromium. Surgical-grade stainless steel, which is used to make medical tools

and implants, contains enough chromium to make the steel corrosion-proof almost

indefinitely.

y Another way of preventing corrosion is using galvanizing steel which is steel that has been

coated with a protective layer of zinc which forms a hard, insoluble oxide. The corrosion

protection remains intact even if there are nicks or scratches in the since layer. Galvanizing

steel requires no maintenance which is also why it is better than paint.

Acids (H+ ions, react with metals and carbonates) and Bases (OH- ions, react with proteins)

Acids

y sour tasting

y compounds contain hydrogen

y water soluble

y compounds split up into ions when mixed with water

o HCl (aq) H + (aq) + Cl²(aq)

y react with metals to produce H2

y good conductors of electricity (because produce ions)

y important in chemical industry:

p sulfuric acid ² fertilizers, explosives, oil refining, electroplating

p hydrochloric acid ² steel, stomach acid, batteries

y Common acids:

p vinegar ² HC2H3O2

p carbonic acid- H2CO3

p Aspirin- HC9H7O4



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p Car battery- H2SO4

Bases

y bitter tasting

y water soluble

y feel slippery

y compounds contain hydroxide (OH)

y when mixed with water - OH ions are released

o NaOH (aq) Na +(aq) + OH ² (aq)

y reacts with protein (hair, skin)

y Uses:

p antacids

p drain cleaner

p soap

p Windex

p cooking (baking powder)

y react with carbonates to produce CO2

y bases can contain OH -, HCO3

pH Scale

y scale to measure how acidic or how basic a substance is

y Log scale- each number goes up or down acidity by a power of 10

y 0 is the most acidic (battery acid)

y 14 is the most basic- alkaline (Drano)

y 8 is 100x less acidic than 6 or 100x more base

y 7 is neutral (equal conc. of Hydrogen ions and hydroxide ions) y soil pH important

p legumes (pH-7-10)

p corn (pH-5-6)

p potatoes and blueberries (pH- less than 5)

pH in cosmetics

y high pH in shampoos (basic)

p dissolve cuticle and damage hair

y Low pH (acidic) ² restores hair

y if you want to straighten curly hair use a higher pH shampoo

y skin ² pH 5-6

N eutralization Reactions (the reaction of an acid and a base to form neutral products, an ionic compound (salt) and water)

y Acid + Base

p product that is close to neutral

p H2O + salt (titration)



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y This can be applied to chemical spills in Northern Ontario

y antacids

Acid Pollutants (sulfur dioxide, nitrogen oxides, buffering) RE AD P AG E 286-290

Sulfur Dioxide

y Sulfur dioxide is a clear, colourless gas that has a strong, choking odour.

y Most of Canada·s production of sulphur dioxide comes from industry which includes burning

coal to generate electricity and the mining and refining of metals.

y Smelting is a process used to separate a metal from the ore extracted from the ground

y smelting involves heating the ore to high temperatures and collecting the molten metal

y during the process, any sulphur present in the ore reacts with the oxygen in the air, forming

sulphur gas: S(solid) + O2(gas) SO2(gas)

y the same reaction tales place during the combustion of fossil fuels ² which generally contain

some sulfur

y once in the atmosphere, sulfur dioxide reacts with more oxygen to produce sulfur trioxide:

2SO2(gas) + O2(gas) 2SO3(gas)

y then sulfur trioxide combines with water droplets in the atmosphere to form sulphuric acid:

SO3 (gas) + H2O (liquid) H2SO4(aq)

Nitrogen Oxides

y most of the nitrogen oxide emissions in North America are produced by vehicles that burn

fossil fuels ² mostly gasoline

y the temperatures inside the internal combustion of a car or train are high enough for

atmospheric nitrogen and oxygen to react to form nitrogen monoxide: N2(gas) + O2(gas)

2NO(gas)

y when nitrogen monoxide reacts with more oxygen it produces a toxic, reddish-brown nitrogen dioxide: 2NO(gas) + O2(gas) 2 NO2(gas)

y in the atmosphere, nitrogen dioxide combines with water to produce nitric acid and more

nitrogen monoxide: 3NO2(gas) + H2O(liquid) 2HNO3 (aq) + NO (gas)

Buffering

y Buffering capacity: is the ability of a substance to resist changes in pH

y it depends on substances in the soil that act like bases, neutralizing the acid

y if a soil·s buffering capacity is high, acids passing through the soil are neutralized before

reaching nearby streams or lakes

y neutralization reactions use up buffering minerals in the soil so the buffering capacity

eventually decreases

y the buffering capacity of a soil partially protects forests from the effects of precipitation

y If the soil has only a small buffering capacity it can only neutralize a small dose of acid. Then

the soil loses valuable nutrients needed to for trees to grow properly.



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2. Tissues, Organs and Organ Systems

Cell theory ² 3 statements

1. All living things are made up of one or more cells and their products 2. The cell is the simplest unit that can carry out al life processes

3. A

ll cells come from other cells; they do not come from non-living matter Eukaryote (true nucleus) and Prokaryote (no true nucleus)

Prokaryote: a cell that does not contain a nucleus or other membrane-bound organelles

Eukaryote: a cell that contains a nucleus and other organelles, each surrounded by a thin membrane

Cell Structures in Plants and Animals- organelles and their functions

Organelle: a cell structure that performs a specific function for the cell

Structure Diagram Description Function

Cytoplas

m y

Fluid substance

y Mostly water

y

Storage until needed

Cell membrane y Flexible y Double layer y Semi-

permeable

y Support cell y Allows some

substances to go into cell and

blocks others out

Nucleus y Spherical structure within the cell

y Contains genetic info that controls

y Controls all activity in the cell

Animal cell

Plant Cell:

(Text p.30)



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all cell activities contains chromosomes that have DNA

y When cell

divides, DNA is copied so each new cell has a complete cell of DNA

Mitochondria y Power plants y Contain

enzymes that help convert stored energy into usable energy

y Cellular respiration

y Fat cells only have 1 or 2mitochondria

y Make energy available to the cells

Golgi bodies y Make secrete mucus

y Collect and process materials to be removed from the cell (package proteins)

Endoplasmic reticulum y 3D network of branching tubes and packets

y Extends throughout the cytoplasm and is continuous from the nuclear membrane to the cell

membrane

y Transport materials, such as proteins throughout the cells

y Assists with production and release of hormones

y Involved with muscle contraction

Vacuole (animal) y Single layer of membrane enclosing fluid in a sac

y Animal cells have many small vacuoles

y Contain some substances

y Removing unwanted substances from the cell

y Maintaining

Animal

vacuoles



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Differences between plant and animal cells

- Plant cells have a cell wall surrounding the cell membrane, and animal cells only have a membrane.

- Plant cells contain chloroplasts which are used for photosynthesis.

- Plant cells have a large vacuole (it's like a fluid sack), compared to an animal cell which has

multiple vacuoles.

often not visible

internal fluid pressure (waste products)

Cell Wall (plants only) y Found outside of cell membrane

y Rigid but porous structure made of cellulose

y May last long after plant is dead

y Provides support and

protection form physical in jury

Vacuole (plants) y Plants have one large vacuole

y Takes up most of space

y When full of water, turgor pressure keeps cells plumped firm

y If water level drops, vacuoles lose turgor pressure and cells become soft, until water is replaced

y Keeps plants· stems and leaves firm

Chloroplasts (plants only) y Contain chlorophyll

y **plant cells can rely on mitochondria to metabolize glucose, like animals do**

y Give leaves green colour

y Absorb light energy which is used in photosynthesis

Plant

vacuole



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-Animal cells are 'blobby', but cells in plants are more structured due to the cell wall, and form a

lattice like structure which helps with rigidness.

-Prokaryotes are found in plant cells and have no nucleus and eukaryotes are found in animal cells

and have a nucleus.

Cell D ivision ( Asexual and sexual)

y Asexual Reproduction: the process of producing offspring from only one parent; the

production of offspring that are genetically identical to the parent.

y Sexual reproduction: the process of producing offspring by the fusion of two gametes; the

production of offspring that have genetic information from each parent.

Reasons for Cell D ivision (reproduction, growth and repair) RE AD P AG E 36-37

Reproduction:

y it is necessary to reproduce and pass on genetic information along

y it is useful so that we can have a larger population

Growth:

y as organisms grow, the number of cells increases which only happens if they divide and

reproduce

y Diffusion: a transport mechanism for moving chemicals into and out of the cell, from an area

of higher concentration to an area of lower concentration

y Concentration: the amount of a substance (solute) present in a given volume of solution

y Osmosis: the movement of a fluid usually water, across a membrane toward an area of high

solute concentration

y When part of an organism is damaged, the remaining cell divide to repair the in jury

Repair:

y cell divides and reproduces which is helpful for repairing the loss of dead skin cells(replaced

by new ones)

y your body replaces each red blood cell every 120 days

y if you break a bone, cells divide to heal the break

y all organisms need to repair themselves to stay alive

Cell Cycle and M itosis

y Cell Cycle: the 3 stages (interphase, mitosis, and cytokinesis) through which a cell passes as

it grows and divides

y Interphase is the time between cell division when a cell grows

y Mitosis:the stage of the cell cycle in which the DNA the nucleus is divided; the first part of the

cell division

y Cytokinesis: the stage in the cell cycle when the cytoplasm divides to form two identical cells;

the final part of cell division

Phases of Mitosis



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1. Prophase: The first stage of mitosis, in which

the chromosomes become visible and the nuclear

membrane dissolves

Words to know

Chromosome: is a structure in the cell nucleus made

up of a portion of the cell·s DNA, condensed into a

structure that is visible under a light microscope

Chromatid: one of two identical strands of DNA that

make up a chromosome

Centromere: the structure that holds chromatids

together as chromosomes

2. Metaphase: the second stage of mitosis, in

which the chromosomes line up in the middle of the cell

3. Anaphase: the third phase of mitosis, in which

the sister chromatids separate into daughter

chromosomes, and each moves toward opposite ends

of the cells

4. Telophase: the final phase of mitosis, in which

the chromatids unwind and a nuclear membrane

reforms around the chromosomes at each end of the

cell

A ging ² telomeres

y Aging is complicated but scientists are researching the causes of aging. There are a lot of possible reasons here are some:

p increasing number of faulty cells (can lead to Alzheimer·s) p errors during DNA duplication and cell division (can lead to kidney and heart failures) p Telomeres

p centromere location y Telomeres are regions of DNA located at the end of each chromosome y their function is to protect the chromosomes from damage during cell division (like plastic at

the end of a shoelace)

y As a cell ages, telomeres get shorter y when telomeres get to short, cell division stops



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Cancer

Tumour

y Tumour is a mass of cells that continue to grow and divide without any obvious function in

the body

Benign

y Benign tumour: a tumour that does not affect surrounding tissues other than by physically

crowding them

Malignant

y Malignant tumour: a tumour that interferes with the functioning of surrounding cells; a

cancerous tumour

Mutation

y Mutation is a random change in the DNA

Carcinogens

y Carcinogen is any environmental factor that causes cancer such as, tobacco smoke;

radiation such as X-rays and UV rays form tanning beds and sunlight; some viruses such as

HPV and Hepatitis B; certain chemicals in plastic; and many organic solvents

Reducing Risk

y Pap test is a test that involves taking a sample of cervical cells to determine if they are

growing abnormally y There are many ways to reduce the risks of cancer and one of them is to make good lifestyle

choices by eating a lot of fruits and vegetables and maintaining a healthy diet

Diagnosing

Endoscope:

y An endoscope is commonly used to screen for colon cancer

y The endoscope is made up of a fibre-optic cable to deliver light, a tiny camera, and a

cable that sends the images to a screen

X-ray

y a mammogram is a specialized X-ray technique for imaging breast tissue

y X-rays can also cause DNA damage especially to a growing fetus, so women who are

pregnant should not undergo X-ray examination



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Ultrasound

y Ultrasound imaging uses ultra-high-frequency sound waves to create a digital image

CT or CAT scan

y A CT scan allows the X-ray technician to take multiple X-rays of the body from many different angles.

y The images are then assembled by computer to form a series of detailed images

MRI

y In an MRI, radio waves and a strong magnetic field create images with more detail

than CT scan

y Computers can assemble the information into 3D models

Examining Cells

y The next step is to examine a sample of suspected cancer cells under a microscope

y This is the only way to confirm a diagnosis of cancer

y Certain cell samples can be obtained easily, such as blood cell samples

y A sample of tumour cells may have to be removed surgically

Treatment

Surgery

y Surgery is physically removing the cancerous tissue

Chemotherapy y Chemotherapy is a method of treating cancer using drugs to kill the cells

y The drugs can be in jected or taken orally(by mouth)

y Chemotherapy is often one of the first stages of cancer treatment

y Its aim is to shrink a tumour for surgical removal or for radiation treatment

Radiation

y Cancer cells are easily damaged by ionizing radiation because they divide rapidly

y The DNA of many of the daughter cells is damaged by the radiation, so the cells cannot

divide further

Biophotonics

y The technology of using light energy to diagnose, monitor and treat living cells and organisms

Specialization of Cells- P AG E 58

Specialized cell: it is a cell that can perform a specific function



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y Specialized cells have physical and chemical differences that allow them to perform one job

very well

Animal specialized cells

Red Blood cells: contain haemoglobin that carries oxygen in blood. The cells are smooth so they can

easily pass through the blood vessels.

Muscle cells: arranged in bundles called muscle fibres. They can contract, which makes the fibre

shorter and causes bones to move.

Fat cells: have a large vacuole which stores fat molecules. This is how it stores chemical energy.

Skin cells: fit together tightly, covering the outside of the body to protect the cells inside and to

reduce water loss.

White blood cells: can move like an amoeba to engulf bacteria and fight infection.

Nerve cells: log, thin, and have many braches. They conduct electrical impulses to coordinate body activity.

Bone cells: collect calcium form food and allow growth and repair of bones. They build bone around

themselves, creating the body·s skeleton.

Sperm cells: able to move independently, carrying DNA from the male to join with an egg form the

female.

Photophores: these are in animals that are mainly active at night and the ones that live deep in the

ocean. They can emit light.

Plant specialized cells

y Some plant cells transport water and dissolved minerals throughout the plant

y Some plants cells dissolve sugars around the plant

Storage cells: contain special structures that store starch, a source of energy for the plant.

Epidermal cells: cells on young roots that have hairs that absorb water from the soil.

Guard cells: in the surface of leaves control water loss.

Photosynthetic cells: contain many chloroplasts to collect energy form sunlight to make sugar for the

plant

Levels of Organization

Hierarchy ² an organization structure, with more complex or imports things at the top and simpler or

less important things below it

Tissue ² a collection of similar cells that perform a particular, but limited, function. There are 4

functions:



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Epithelial (skin, lining of digestive system)

y Thin sheets of packed cells

y Protection, insulation, inhibits dehydration

Connective (bone, tendons, blood)

y Held together by a liquid, solid, or gel

y Support

Muscle Tissues (skeletal, cardiac, smooth)

y Long cells called fibres

y Movement

Nerve Tissue (brain, sense, organs)

y Long, thin, cells with fine

y Branches carry electrical impulses

Organ ² a structure composed of different tissues working together to perform a complex body

function. Each organ system is made up of highly specialized organs and other structures that work

together to perform the overall function of the systems. Most organs work within a single organ

system. Some organs, however, play a role in more than one system.

Organ System ² a system of one or more organs and structures that work together to perform a

ma jor vital body function such as digestion or reproduction. They obtain oxygen and nutrients and

eliminate wastes. They all sense and respond to their environment, grow and repair damage &

reproduce.

Stem Cells- cell differentiation (cord blood, transplantation, regeneration) P AG E 77

Cellular differentiation: is the process by which a cell becomes specialized to perform a specific

function

Stem cell: an undifferentiated cell that can divide to form specialized cells

y A stem cell divides into two daughter cells through the processes of mitosis and cytokinesis

y Each resulting daughter cell can develop into a different type of cell, based on which parts of

its DNA are switched on ]they generally occur in clumps that differentiate into different tissue

layers, such as epithelial, muscle, and nerve tissues

y There are two types: embryonic that can differentiate into any kind of cell and tissue stem cells that exist within specialized tissue (only able to differentiate into certain types of cells)

Cord Blood

The blood found in the umbilical cord immediately following birth is a rich source of stem cells. These

are not embryonic stem cells; they are more similar to tissue stem cells. They can develop into any of

the various kinds of blood cells. Umbilical cord blood has a high concentration of these tissue stem



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cells and is relatively easy to obtain. This collected blood could be ´bankedµ in case it is needed

later.

Tissue Stem Cell Transplantation

Both cord blood and bone marrow stem cells are relatively easy to isolate. It·s used to cure leukemia.

Leukemia is a cancer that occurs in the bone marrow. The stem cells that differentiate into blood cells divide too quickly, resulting in non ² functioning blood cells. Chemotherapy can target and kill

bone marrow cells and white blood cells. Healthy bone marrow cells are obtained from a carefully

matched donor. The healthy stem cells are then in jected into the patient·s blood.

Regeneration

Regeneration has the ability of a tissue to repair itself. Skin, muscle, and bone can regrow and heal

after an in jury. Not all cells regenerate.

D igestive System- mouth, esophagus, stomach, intestine, liver, pancreas, gall bladder P AG E 80

(T

extbook page 80)

Mouth ² process of breaking down food in

2 ways with teeth and tongue and

chemically with chemicals called enzymes

that break apart the molecules of food

Esophagus ² muscles are a special type,

called smooth muscle tissue, which can

contract and relax without conscious

thought. Movement is controlled by nerve tissue.

Stomach ² holds food and turn it to

continue the process of digestion.

Produce digestive enzymes and acids. Mix the stomach contents ² mucous + acid (HCl) + enzymes,

protein, acids kills bacteria

Intestine ² intestine has cells that produce mucus. Also has many blood vessels interlaced through

the other tissue

2 parts to the intestine:

Small intestine is narrow and where most digestion occurs. Goblet cells release mucus, & nutrients

diffuse through the wall of the small intestine and enter the bloodstream

Large Intestine lining absorbs water from the indigestible food. Remaining solid matter is excreted as

feces from the anus

Accessory Organs



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y The liver, pancreas, and gall bladder all help with the digestion of food by supplying digestive

enzymes

y The liver produces fluid called bile, which helps breakdown fats in our food

y Pancreas produces insulin which regulates the concentration of glucose in the blood

Circulatory System- blood, heart, arteries, veins, capillaries, coronary artery diseases, heart attack (Textbook page 83)

The 3 main parts of the circulatory system are

the blood, the heart, and the blood vessels.

Blood: blood is a type of connective tissue that

circulates throughout all parts of your body. The

blood consists of 4 components

p Red blood cells ² contain a protein called haemoglobin, which allows them

to transport oxygen throughout the body

p White blood cells ² they

recognize and destroy invading bacteria and

viruses. They are the only blood cell that has a

nucleus

p Platelets - tiny cells that help in

blood clotting

p Plasma ² is a protein ² rich liquid that carries the blood cells along

Heart: the heart is made up of 3 different types of tissues: cardiac muscle tissue, nerve tissue, and

connective tissue. All of the cardiac muscle tissue in each part of the heart contacts at the same

time. The muscles and nerves are covered by a smooth layer of epithelial tissues. This covering

reduces friction and protects the heart from damage when the lungs expand and contract. The inner

surface of the heart, where the blood to flow freely.

Arteries

y Is a thick walled blood vessel that carries blood away from the heart.

Veins

y Is a blood vessel that returns blood to the heart.

Capillaries

y is a tiny walled blood vessel that enables the exchange of gases, nutrients and wastes

between the blood and the body tissues



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Coronary Artery Disease

y coronary arteries are blood vessels that provide blood to the heart tissue

y these vessels can become partially blocked with plaque (a deposit made of fat, cholesterol,

calcium etc. that usually circulate in the blood)

y causes: genetic information, poor lifestyle choices (high-fat diet, smoking, less exercise)

y symptoms: tiredness, dizziness, pain or burning sensation in chest or arms

y problem can be diagnosed by angiogram (a special X-ray), in which fluorescent dye is in jected

into bloodstream, then dye shows up on X-ray image

Heart Attack:

y coronary arteries can become completely blocked then heart muscle cells no longer receive

oxygen and nutrients they need to function

y so heart stops pumping and heart tissue starts to die

y Symptoms: chest pain/pressure, shortness of breath, nausea, dizziness etc.

y Can be diagnosed with blood test and electrocardiogram y The electrocardiogram (ECG) measures the electrical signals created by the heart as it beats

«e.g.:

Respiratory System

(Textbook page 91)

Respiratory system: the organ system that

is made up of the nose, mouth, trachea, bronchi, and lungs; the system that

provides oxygen for the body and allows

carbon dioxide to leave the body

y Air enters through mouth and nose,

passes through the pharynx (throat) and

travels down the trachea (windpipe)

y Trachea separates into 2 braches,

bronchi

y Some epithelial that line the

trachea and bronchi produce mucus

y Epithelial cells have cilia (hair like

pro jections)

y Cilia help move mucus and filter

out any foreign material

y Bronchi deliver air to lungs



By: Vinny 22

Gas Exchange

Oxygen enters the bloodstream in the lungs by diffusion. Carbon dioxide leaves the blood in the

same way. Each of the bronchi branch again & again, ending in tiny air sacs called alveoli. The alveoli

have very tiny walls. Each is surrounded by a network of capillaries. Oxygen and carbon dioxide have

only to diffuse through two thin walls: the walls of the capillaries and the walls of the alveoli. It

switches the oxygen to CO2

Breathing

Breathing involves alternately drawing air into the lungs (inhalation) and then pushing air out

(exhalation). This process involves muscles that move the ribs, making the rib cage expand and

contract. Breathing also involves the diaphragm and the muscles between the ribs increase and

decrease the volume of the lungs. The pressure inside them also changes.

Breathing is controlled by a part of the brain that detects the concentration of carbon dioxide in the

blood. As the level of carbon dioxide increases, the brain sends signals to the diaphragm, the

muscles between the ribs, and the heart.

Tuberculosis:

y Infectious disease

y Caused by bacteria that enter your body when you breathe

y Bacteria grow in lungs, can spread to body

y Chest X-ray is one of the best test used to diagnose this

y Medical technicians may examine samples of stomach or lung secretions

y Symptoms: fever, cough, weight loss, tiredness, chest pain

SARS

y Severe Acute Respiratory Syndrome

y Symptoms: high fever, short breath, dry cough, sore throat, headache, muscle pain, and

exhaustion

y Chest x-ray show evidence of pneumonia and cell samples are taken from patient

Organ Transplantation

y Some organs that can successfully be transplanted include: heart, liver, lung, pancreas, and

intestines

y Transplantable tissues include: cornea, skin, bone, bone marrow, tendons, and blood vessels

Benefits Risks

y Recipient can live a healthy, normal life

y Donor has the satisfaction is knowing that they saved

someone·s life

y Medical researchers gained a lot of new knowledge

y Re jection; the recipient·s immune system may recognize the new organ as a foreign material and try to destroy it

y Patient will need to take drugs to prevent the immune system from re jecting new



By: Vinny 23

tissue or organ

y With immune system suppressed by drugs the body· ability to fight off infections is reduced

Living Donor Organs

y Organs from living donors include: a kidney, a lobe of one of their lungs, or a part of their

liver.

y Living donor lung transplantation requires 2 donors, each giving one lobe

y Kidney transplantation only requires 1 donor

y In the case of a liver transplantation, doctor remove one lobe form donor and transplant to

recipient. Live has ability to regenerate or grow gain. Over time, the transplanted lobe will

form new tissue and function. The donor·s liver will also regenerate new tissue to replace the

removed portion

Deceased Donor Organs

y Donor or donor·s family gives consent to donate organs after death

y Organs must be checked to determine whether they are healthy and undamaged

y Medical professionals take into account blood and tissue types, age and location of donor,

and how long recipient had been waiting for a transplant

Xenotransplantation

y It is the process of transplanting an organ or tissue from one species to another

y Heart valves from pigs have been used to replace damaged human heart valves. However

these valves have been chemically treated to kill cells so they are no longer considered living tissue

M usculoskeletal System (P AG E 99)

y Consist of the bones, ligaments, and cartilage

Connective Tissue

y Bones consist of cells within a matrix of minerals and collagen fibres. Canals inside the bones contain nerves

and blood vessels.

y Ligaments are tough, elastic connective tissues that

hold bones together at the joints.

gament



By: Vinny 24

y Cartilage is a dense connective tissue found in the ear, nose, esophagus, the disk between

our vertebrate and joints Fibres provides a strong, flexible, low ² friction support for bones

and other tissues.

Muscles

y Skeletal muscles that is attached to the bones by tendons, allowing the movement of body

parts

y The main role of the skeleton is to provide structure and support for our bodies and anchor

points for our muscles

y Some bones protect the soft internal organs and brain

y Skeletal muscle is used for voluntary movements of the body, such as walking

y When muscles contract in response to signals from the nervous system, they exert a force.

y They move one or both of the bones to which the muscles is connected

y 650 muscles 40% body mass

A MUSCLE

N ervous System ² P AG E 140

Nervous system: the organ system that is made up of the brain, the spinal cord, the peripheral nerves; the system that senses the environment and coordinates appropriate responses

p Central Nervous System ² consist of the brain and spinal cord. The nerves that carry signals

between the central nervous system and the body make up the peripheral nervous system.

Peripheral nervous system relays information about the internal and external environments

to the brain. It also relays instruction from the brain to other parts of the body to control

many of the body·s functions and responses.



By: Vinny 26

y The musculoskeletal system uses the circulatory system to deliver constant supply of oxygen

and nutrients and it must remove wastes

y These wastes enter the blood by diffusion through capillary walls and are carried away for

disposal

y The blood collects waste products as it travels through all the body·s tissues. The blood

passes through the kidneys and the unwanted toxic substances are removed (urine). y FOR MORE INTERACTIONS GO TO PAGE 110

Systems in Plants

Shoot System

y It is the system in a flowering plant that is specialized to conduct photosynthesis and

reproduce sexually; it consists of the leaf, the flower, and the stem

Leaf

y In photosynthesis, tissues in the leaf use carbon dioxide, water, and light energy to produce

glucose and oxygen.

y The glucose is used for plant growth, cellular respiration, and energy storage

y PHOTOS Y NTHESIS

Light energy + carbon dioxide + water glucose + oxygen

y The cell structure that actually performs photosynthesis is an organelle called chloroplast

y Chloroplasts contain flat, disc-like structures called thylakoids

y Thylakoids are arranged in stacks called grana

y These stacks act as solar collectors, using chlorophyll in the membranes of thylakoids

Flower

y Flowers are specialized structures developed for sexual reproduction

y They contain male or female reproductive structures, sometimes both

y Male reproductive structures produce pollen grains; female reproductive structures produce

eggs

y Eggs are fertilized by pollen then the female flower parts form seeds

y In most flowering plants, the seeds are contained within a specialized structure called a fruit

y Pollination occurs by wind or animals

y Mosses, ferns, and coniferous trees are not flowering plants

y Conifers are all wind pollinated and they produce pollen and seed in specialized cones

Stem

y It supports the branches, leaves, and flowers and provides a way to transport materials

y Contains significant amounts of vascular tissue for carrying substances to and from roots,

leaves, flowers, and fruit.

Root System

Chloro h ll



By: Vinny 27

y It is the system of a flowering plant, fern, or conifer that anchors the plant, absorbs water

and minerals and stores food

y It typically grows below ground

y Examples include: radishes, carrots (the roots are used for nutrient storage), sweet potatoes,

sugar beet, ginger etc.

Dermal Tissue System

y It is the tissues covering the outer surface of the plant

y Do not occur within the plant

y Includes epidermal and periderm tissues

y Epidermal tissue (epidermis): a thin layer of cells covering all non-woody surfaces of the plant

y Most epidermal leaf cells produce a layer of wax, called the cuticle, that helps waterproof the

leaf·s surface

y Some epidermal leaf cells are adapted for defence, they have hair like structures that

contain chemical irritants

y Some epidermal root cells have long extensions called root hairs to help absorb water and minerals form the soil

y Periderm tissue: tissue on the surface of a plant that produces bark on stems and roots

Vascular Tissue System

y it is the tissues responsible for conducting materials within a plant

y it transports the water, minerals and other chemicals around the plant

y like a network of tubes, that reaches from the roots, up the stalk, and through the leaves

y there are two types: xylem and phloem

y xylem: is a vascular tissue in plants that transports water and dissolved minerals from the

roots to the leaves and stems of the plant

p they are hollow tubes with rigid walls

p have no cytoplasm, nucleus, or other organelles

p mature xylem cells are no longer living tissue

y phloem: vascular tissue in plants that transports dissolved food materials and hormones

throughout the plant

p under certain conditions, food materials are transported downward from the

photosynthesizing leaves to the stem and roots

p made up of elongated cells that are alive and functioning

Ground Tissue System

y they are all plant tissues other than those that make up the dermal and vascular tissue

systems

y they perform variety of functions such as in the green parts of the plant, they manufacture

nutrients by the process of photosynthesis

y in roots they store carbohydrates

y in stems they provide storage and support



By: Vinny 28

Photosynthesis

Light energy + carbon dioxide + water glucose + oxygen

Specialized tissue and Cells in a Leaf

y Palisade layer: a layer of tall, closely packed cells containing chloroplasts, just below the

upper surface of a leaf; a type of ground tissue y Close packing helps palisade cells capture as much incoming light as

possible

y Spongy Mesophyll: a region of loosely packed cells containing chloroplasts, in the middle of a

leaf; a type of ground tissue

y Spaces between the spongy mesophyll cells permit gasses to move around

within the leaf

y Cuticle: a layer of wax on the upper and lower surfaces of a leaf that blocks the diffusion of

water and gases

y Stomata: (stomate: singular) an opening in the surface of a leaf that allows the exchange of

gases

p Ma jority of plants have most or all of their stomata in the lower surface of the

leaf

p This location reduced water loss, provides more surface area for

photosynthesis , and reduces the chances of airborne viruses, bacteria, and

fungal spores from entering the leaf

p When it is open carbon dioxide can enter and oxygen can be released

y Guard cell: one pair of special cells in the epidermis that surround and control the opening

and closing of each stomate

p The guard cells can either bend outward, causing stomata to open, or they

can collapse inward, causing stomata to close

p Have a mechanism that responds to light levels which helps them close the stomata at night when carbon dioxide is not needed because there is no light

for photosynthesis

Plant Growth

Apical and lateral meristems

y Apical meristem: undifferentiated cells at the tips of plant roots and shoots; cells that divide,

enabling the plant to grow longer and develop specialized tissues

p When they first divide in the tips of the roots, many of them begin to elongate

p As they elongate, they differentiate into specialized cells of the dermal,

ground and vascular tissue systems y Lateral meristem: undifferentiated cells under the bark in the stems and roots of woody

plants; cells that divide, enabling the plant to grow wider and develop specialized tissues in

the stem

p They form 2 cylinders, one inside the other, that run the full length of the

shoots and roots

Chloro h ll



By: Vinny 29

p As plant grows in diameter, the outer lateral meristem produces new dermal

tissue, called cork, to replace old epidermal cells

p Inner lateral meristem produces new phloem tissue on its outer surface and

new xylem tissue toward its interior

p Many plants do not have lateral meristem so their stems and roots cannot

grow any thicker once the first tissues formed by the apical meristems have matured

Vegetative Reproduction

y It is the process in which a plant produces genetically identical offspring from its shoots or

roots

y Examples are strawberry plants that reproduce vegetatively by sending out shoots called

runners across the surface of the soil

Tissue Culture

y Tissue culture propagation: a method of growing many identical offspring by obtaining

individual plant cells from one parent plant, growing these cells into calluses, and then into

whole plants

y Calluses: clumps of cells which can be separated over and over again, producing unlimited

number of growing cell masses

p Chemicals can be added to each callus anytime

p These chemicals act like plant hormones and trigger the callus cells to begin

the processes of growth and differentiation and the end result is a new plant

3. Light and Geometric Optics

W hat is light?

y Light travels through the vacuum of outer space

y Light does not require a medium for transmission, instead it is transferred through radiation

y Electromagnetic waves: radio waves, X-rays, microwaves, radar, and ultraviolet light

Electromagnetic Spectrum RE AD P AG E 466 for Types of waves (microwaves etc.)

Electromagnetic spectrum: the classification of electromagnetic waves by energy

DIAGRAM:



By: Vinny 30

Colours and Visible Light

y White visible light is composed of continuous sequence of colours, called the visible

spectrum

y Has seven distinct colours: red, orange, yellow, green, blue, indigo, and violet

y Newton was the first scientist to discover that seven distinct colours were visible in white

light

How is Light produced?

Incandescence (diagram on the left«sorry I couldn·t

find one so I had to make one quickly):

y high temperature wire

y a lot of heat- inefficient

Electric Discharge:

y Current through a gas (neon, xenon, halogen)

y Lightening

Phosphorescence:

y Glow in the dark (phosphor)

y Absorb UV light and store it, releasing it later

Fluorescence:

y Absorb UV light and immediately release visible light (fluorescent clothing-dye)

Chemiluminescence:

y Chemical reaction- light (glow sticks)

Bioluminescence:

y Chemiluminescence in living organisms (fish, fungus, bacteria, fireflies, glow worms)

Triboluminescence:



By: Vinny 32

*Basically the incident ray comes and hits then reflects on the other side of the normal on the same

angle.*

Terminology

y Image: reproduction of ob ject

y Perpendicular: right angle of 90

y Normal: ray perpendicular to mirror

y Incident ray: coming into mirror

y Reflected ray: leaving mirror

y Plane: flat

y Angle of incidence: the right angle between the incident ray and the normal

y Angle of reflection: the angle between the reflected ray and the normal

The Laws of Reflection

1. Angle of Incidence = Angle of Reflection

2. Reflected and incident ray are on the same plane/surface

2 TY PES OF REFLECTION

p Specular- smooth, shiny (disco balls, very still water, flat aluminum foil



By: Vinny 33

p Diffuse- rough, dull (sheet of paper, water surface with waves, crumpled aluminum

foil)

I mages in Plane M irrors

A. Light Ray Method (more complicated, but will be asked on test to do)

Basically, you have an ob ject on one side, then you take every vertex (two lines meet) and draw

two rays from each point to the mirror (on any angle), then find the reflected ray (make sure this

is on the same side as the ray you drew)«after you find the reflected ray (by measuring the angle

of the ray you drew from the normal)then extend the lines of the REFLECTED ray behind the

mirror until they meet(because that·s where your brain sees it, not actually there) that is how you

find the first point. Do the same to find the second point (and so on), andthen join in the space in

between.This might be a little confusing so look at the diagram (it is colour coated with the

words). (Obviously it isn·t perfect because I drew it on paint)

B. Perpendicular Lines (Way easier)

Basically, draw a straight line from a point of the ob ject to the mirror and measure it, then

draw a line on the other side of the mirror of the same measurement and that is your first



By: Vinny 34

point.Do the same with the rest of the points,and fill in the space. (This is also color

coordinated and not perfect because drawn by me on paint, but pretty close)

Acronym S ALT SALT: when you describe the properties of an image, you need to examine 4 characteristics:

p Size: compare the image to ob ject; is it same size, smaller, or larger

p Attitude: which way is the image oriented compared to the ob ject; upright or inverted

p Location: location of image (behind or same side as ob ject)

p Type: real or virtual

REMEMBER: an image in a plane mirror is always the same size as the ob ject (Size), upright but

laterally (horizontally, reverse order) inverted (Attitude), behind the mirror (Location: the same

distance behind as the ob ject as in front), and virtual (Type).

Curved M irrors

y Concave (converging) mirror: a mirror shaped like part of the surface of a sphere in which the

inner surface is reflective, like this:)« Image can be real or virtual

y Convex (diverging) mirror: a mirror shaped like a part of the surface of a sphere in which the

outer surface is reflective, like this: («Image is always virtual

y Centre of curvature: the centre of the sphere whose surface has been used to make the

mirror

y Principle axis: the line through the centre of curvature to the midpoint of the mirror

y Vertex: the point where the principle axis meets the mirror

y Converge: to meet at a common point y Focus: the point at which light rays parallel to the principal axis converge when they are

reflected off a concave mirror

y Real image: an image that can be seen on a screen as a result of light rays actually arriving

at the image location

y Diverge: spread apart



By: Vinny 35

LOC ATE IMAG E IN CO N VERGING MI RROR

Basically there are 2 ways to do it, sometimes the easy way works and sometimes it doesn·t, you

have to try both (I always try the easy one first), but I will show the hard way first (make sure you

know your definitions because I will be using those in here). THIS IS HOW I THINK OF FINDING AN

IMAGE,BUT FOR COMPLETE INTRUCTIONS THE RULES ARE ON PAGE 497

HARD WA Y

1. Draw a principal axis

2. That will reflect through the focus point

3. Take the tip of the arrow/ ob ject and go through to vertex

4. Now this is why it·s not as easy, you have to measure the angle of the line (with a

protractor) at the vertex and make the same angle reflecting ´underµ

5. Where the two lines join is the tip of the arrow/ob ject, then fill in the space

EAS Y WA Y - WORKS WHENEVER THE OBJECT IS AT OR AFTER THE CENTRE OF

CURVATURE

1. Draw principal axis

2. That reflects through focus

3. Go from tip of arrow/ob ject through the focus

4. Reflect parallel to the principal axis

5. Wherever the two lines meet, is the tip of the arrow/ob ject, fill in the space



By: Vinny 36

Many uses such as: car headlight, flashlight, searchlight, reflecting telescope, satellite dishes

The imaging properties of a converging mirror (USING SALT):

*C= centre of curvature, F= Focus)

OBJECT IMAGE

LOC ATE IMAG E IN DI VERGING MI RROR

THERE IS ONL Y ONE WA Y «THESE IMAGES WILL BE ´BEHINDµ THE MIRROR

Since the image is going to be behind the mirror, you will need a focus behind the mirror, to do that

measure the distance from the focus to the mirror, and use that same distance to make a focus

behind the mirror.THIS IS HOW I THINK OF FINDING AN IMAGE,BUT FOR COMPLETE INTRUCTIONS

THE RULES ARE ON PAGE 500

1. Draw principal axis, this time the light will reflect back

2. From the principal axis, take the point where it touches the mirror and extend it back through

the focus, behind the mirror

3. Take the tip of the arrow and draw it to the vertex, measure the angle

4. Reflect the same angle ´underµ

5. The reflected ray from the vertex will extend backwards, behind the mirror

6. Wherever the 2 rays behind the mirror meet is the tip of your arrow, ob ject, fill in the space

Location Size Attitude Location Type Beyond C Smaller Inverted Between C &F Real At C Same size Inverted At C Real between C &F Larger Inverted Beyond C real At F NO CLEAR IMAGE P RODUCED!

Inside F Larger Upright Behind mirror virtual

REMEMBER!!!

y IMAGE INFRONT OF THE

MIRROR AND UPSIDE DOW

IS REAL



By: Vinny 37

The imaging properties of a diverging mirror:

y A convex mirror ALWA Y S produces a smaller virtual image

Many uses such as: side mirrors on cars, security mirror in stores

Refraction

p This is when light changes direction when travelling one medium to another

p E.g. ² speed of light: 3 x 108 m/s (meters per second)

Water: 2.26x 108 m/s

Acrylic: 1.76 x 108 m/s

RU L ES OF REFR ACT I O N

1. The incident ray, the refracted ray, and the normal all lie in the same plane. The incident ray and refracted ray are on opposite sides of the line that separates the two media (medium,

e.g. air water)

2. Fast medium to slow (air water) Light bends toward the normal

Slow medium to fast (water air) Light bends away from the normal

I ndex of Refraction

p Ratio of light in a vacuum and the speed in a medium

REMEMBER!!!

y IMAGE BEHIND THE

MIRROR, RIGHT SIDE UP IS

VIRTUAL



By: Vinny 38

n= index of refraction

c= speed of light in a vacuum (this is always 3 x 108 m/s)

v= speed of light in a medium

So, your equation is n= c/v USE THIS TRIANGLE: cover with your hand the stuff you want to find out

** n , v (inversely related) **

E.g. Calculate the speed of light in Quartz

Given: c= 3 x 108 m/s (this has to be MEMORIZED)

v= ?

n= 1.76 (this will be given on the test in a question to find v)

Calculation:

v= c/n

= 3 x 108 m/s ***At this part just divide 3/1.46 and put the 108 after in the answer***

1.46

=2.05 m/s x 108

E.g. Calculate the index of refraction for vinegar

Given: c= 3 x 108 m/s (this has to be MEMORIZED)

v= 2.30 x 108 m/s (this will be given on a test in a question to find n)

n= ?

Calculation:

n= c/v

n= 3 x 108 m/s

2.30 x 108 m/s ** The 10

8

m/s crosses out with each other**



By: Vinny 39

Critical Angle

REMEMBERCritical angle: the angle of incidence that results in an angle of refraction of 90

In the diagram above, the critical angle is when the angle of incidence is at 50, it refracts at 90.

Since the medium is going from slow fast (water air) anything above the critical angle refracts

away from the normal. Anything below the critical angle will reflect on the other side (on the same

angle).

Total I nternal Refraction

y Total internal reflection: the situation when the angle of incidence is greater than the critical

angle

**IMPORTANT: a larger critical angle = more refraction, less reflection (as shown in the diagram

above)

a smaller critical angle = more reflection, less refraction

Uses: a diamond is sparkly because it has a low critical angle, most of the light rays reflect instead of

refract

Phenomena Related to Refraction

Depth: PAGE 535

y Apparent depth is the depth that an ob ject appears to be at due to the refraction of light in a

transparent medium



By: Vinny 40

y ob jects under water always appear to be nearer to the surface than they actually are. This is

what makes fish in water appear to be closer to the surface than they are.

y for same reason, legs of someone standing water appear to be shorter

y apparent depth is an optical illusion

Mirage: PAG

E 537

y a mirage is a virtual image that forms as a result of refraction and total internal reflection in

Earth·s atmosphere

y a mirage can appear when light is travelling from cool air into warmer air

y the index of refraction decreases as the air gets warmer

y this results in light bending farther away from the normal as the air temperature continues to

increase

y eventually total internal reflection occurs in the lowest (hottest) air layer

y light ray travels up form hottest layer into cooler layer above and is gradually refracted

toward the normal as the temperature decreases

y light ray eventually enters eyes

Shimmering: PAGE 537

y shimmering is caused by light being refracted as it passes through air of different

temperatures

y moonlight passes through layers of air that have different temperatures

y in the coldest air layer, light travels more slowly so a light ray going through this layer bends

toward the normal

y as the light ray continues travelling downward toward the warmest layer (just above the lake),

its speed increases, so the light ray bends farther and farther away from the normal

y eventually total internal reflection occurs in the lowest warm air layer, this results in multiple

virtual images of Moon on the water·s surface

Rainbow: PAGE 538

y produced by water droplets in Earth·s atmosphere

1. refraction as light enters the raindrop (going form air to water) resulting in dispersion

2. partial internal reflection when this light hits the back of the raindrop

3. Refraction as the light now exits the raindrop (going form water to air). This is the

light that your eyes see, which you perceive as a rainbow

4. your brain pro jects these light rays backwards and forms a virtual image of the

spectrum: a rainbow

**you can only see a rainbow when the Sun is behind you**

Lenses

y Converging lens: a lens that is thickest in the middle and that causes incident parallel light

rays to converge through a single point after refraction. Real or virtual images created.



By: Vinny 41

y Diverging lens: a lens that is thinnest in the middle and that causes incident parallel light

rays to spread apart after refraction. Only virtual images created.

I mages in Lenses ² Converging

THERE IS ONL Y ONE WA Y ...DON·T CONFUSE THIS WITH MIRRORS³THIS IS LENS

To find an image in a converging lens:

1. Draw a principle axis

2. This reflects through the vertex

3. Take the point of the principal axis on the other side and go through the focus

4. Wherever the two lines meet, that is your image, in this case it is the tip of the arrow, fill in

the space

The imaging properties of a converging lens

*F= focus, 2F= 2x the focus length*

OBJECT IMAGE

Uses: the camera (p. 567), the movie pro jector (p.568), the magnifying glass (p. 568), the compound

microscope (p. 569), the refracting telescope (p. 569)

D iverging Lens

THERE IS ONL Y ONE WA Y

To find an image in a diverging lens:

1. Draw a principle axis

2. This reflects through the vertex

3. Take the point of the principle axis (on the same side) it reflects back to the focus

Location Size Attitude Location Type Beyond 2F Smaller Inverted Between 2F &F Real At 2F Same size Inverted At F Real between 2F &F Larger Inverted Beyond 2F Real At F NO CLEAR IMAGE P RODUCED!

Inside F Larger Upright Behind mirror Virtual

Converging lens can produce real

and virtual images, but in this case it

is real because it is inverted. And the

image is behind the mirror.



By: Vinny 42

4. Wherever the two lines meet is the tip of the arrow, fill in the space

The imaging properties of a diverging lens:

The image is always smaller, upright, virtual and on the same side of the lens as the ob ject. The

human brain perceives it as virtual by extending the diverging rays backwards to a virtual source.

Lens A pplication

Camera: PAGE 567

y a camera take slight form large, distant ob jects, and forms smaller, real images on either

film in traditional camera or the sensor in a digital camera

y this means that the ob ject must be located at more than twice the focal length of the

lens (beyond 2F·)

y a traditional film camera uses flexible roll film to capture images

y today digital cameras use light sensitive device made of silicon called charge-coupled

device (CCD)

Movie Pro jector: PAGE 568

y opposite to a camera

y pro jector takes a small ob ject (the film) and pro jects a large, inverted, real image on a screen

y because the image is larger it must be located between F· and 2F·

y the film must be loaded into the pro jector upside down so that what you see on the screen is

upright

Magnifying Glass: PAGE 568-569

y simple converging lens which the ob ject is located between F· and the lens

y no real image is produced at this ob ject location

y refracted rays diverge, but human brain extends rays backwards and produces and enlarged,

virtual image located on the same side of lens as the ob ject

Compound Microscope: PAGE 569

y an arrangement of two converging lenses

This image is virtual and in front of

the lens



By: Vinny 43

y produces 2 enlarged, inverted images: one real and one virtual

y real image formed by ob jective lens; cannot see this image because it is in body of tube

(between the eyepiece and lenses)

y virtual image is formed by the eyepiece lens; this is the larger, virtual image you see

Human Eye

The camera and eye are very alike:

y The camera has a diaphragm that controls the amount of light entering it, the iris has this

function

y The hole in the iris is called a pupil, comparable to the aperture in a camera, and is where

light enters the eye

y A camera has a converging lens to refract light to form a sharp image. The eye also has

structures (lens and cornea) that cause light to converge

Eye Focusing Problems

Farsightedness- hyperopia

p See things farther away well but not up close

p To fix this use a converging lens to focus light on the retina, positive meniscus

With lens

Near sightedness- myopia



By: Vinny 44

p See up close not distant

p To fix this use a diverging lens to diverge light to focus on retina, negative meniscus

With lens

Presbyopia

p As people get older they find it harder to read because eye lens loses elasticity

p Can be corrected by converging lens

Contact Lens

y Positive-meniscus: a modified form of the converging lens shape

y Negative meniscus: a modified form of the diverging lens shape

y Contact lens: a lens that is placed directly in the cornea of the eye

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