-the organized way that scientists solve problems - consists of very specific steps

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-The organized way that scientists solve

problems

- consists of very specific steps

Hypothesis - an “educated” guess, or one which occurs after researching

Important in experiment design:

- Useful experiments have only 1 variable.

Variable - factor being tested

control - experiment without the variable.

- Useful experiments collect enough data or observations to draw a conclusion.

Observations – what happened during the experiment that was seen, smelled, tasted, felt, or heard

Data - recorded measurements of changes that occurred during the experiment

Data tables – charts the represent data neatly and clearly

Graphs – bar graph, line graph, pie graph, or whatever kind of graph would properly represent the data

A theory is the most logical explanation about events that occur in nature. It has been tested repeatedly.

Law - if a theory holds up after a long time

There are two versions of the idea

• Spontaneous Generation/Abiogenesis: Life forms can arise spontaneously from non-living matter.

• Biogenesis: Living things can only come from other living things.

Which is true?

All living things are made up of cells.

• Cells are the smallest units of an organism that can be considered alive.

• Some organisms are unicellular (made of 1 cell) and some are multicellular (made of more than 1 cell).

All living things reproduce.

• Reproduction is the production of new organisms.

• Some living things reproduce sexually (with 2 parents).

• Other living things reproduce asexually (1 parent).

All living things need materials and energy.

• Autotrophs get their energy from the sun and make their own food.

• Heterotrophs get their energy from their food.

All living things maintain internal balance.

• Homeostasis is the process of keeping internal conditions stable.

Functions of Carbohydrates in Cells• Used for energy

– Energy is stored in Adenosine TriPhosphate (ATP)

• Used to communicate between cells

• Used to store energy

• Used to provide support for cells• Made up of monosaccharides (glucose)

Testing for Carbohydrates

• The Benedicts Test is used to detect simple carbohydrates (sugars)

• The Iodine test is used to detect complex carbohydrates (starches)

Functions of Lipids in Cells• long term storage of energy• create membranes around cells to be a barrier

for a cell– Lipids make good membranes because they are

hydrophobic (water fearing)

• lipids are base molecules for hormones (chemical signals the body uses to direct some of its activities)

• Tested in foods with the Sudan Test• Made up of glycerol and fatty acids

Functions of Proteins• Used for structure of a cell

• found in membranes - control what goes in and out of a cell

• used to communicate with other cells

• used as enzymes (bring about a chemical reaction in an organism)

• The Biuret test is used to detect proteins in foods.

Enzymes

• Protein that speeds up a chemical reaction without being used by the chemical reaction

Ecology

• The scientific study of interactions among organisms and between organisms and their environment

Biosphere

• The largest level of organization of the living world

• Contains the part of the planet on which all of life exists

• Includes land, water, and atmosphere

• Extends from 8 kilometers above the Earth’s surface to 11 kilometers below the surface of the ocean

Species

• One of the levels of organization

• Group of organisms so similar to one another that they can breed and produce fertile offspring

Population

• One of the levels of organization

• Groups of individuals that belong to the same species and live in the same area

Community

• One of the levels of organization

• Groups of different populations of different species that live together in a defined area

Ecosystem

• One of the levels of organization

• Collection of all the organisms that live in a particular place, together with their nonliving environment

Biome

• One of the levels of organization

• A group of ecosystems that have the same climate and similar communities

Producers

• Organisms that can capture energy from sunlight and use that energy to produce food

• Producers are also called autotrophs because they make their own food.

Photosynthesis

• Process in which autotrophs use light energy to power chemical reactions that convert carbon dioxide and water into food oxygen

• Adds oxygen to the atmosphere

• Removes carbon dioxide from the atmosphere

Consumers

• Organisms that cannot harness energy directly from the environment

• Get their energy from food

• Also known as heterotrophs

Groups of consumers

• Herbivores are consumers that eat only plants• Carnivores are consumers that eat only meat• Omnivores are consumers that eat both plants

and animals• Detritivores are consumers, like earthworms,

snails, crabs, and mites, that feed on plant and animal remains and other dead matter

• Decomposers are consumers, like bacteria and fungi, that break down organic matter

Food Chain

• A series of steps in which organisms transfer energy by eating and being eaten

• A food chain always begins with a producer, which is eaten by an herbivore or omnivore, which is eaten by a carnivore or omnivore, and eventually is decomposed by a decomposer and eaten by a detritivore.

Food Web

• A network of complex interactions that shows the feeding relationship among the various organisms in an ecosystem

• Links all the food chains in an ecosystem together

Trophic Level

• Each step in a food chain or food web

• Producers are the first trophic level

• Consumers are the second, third, and higher trophic levels

• Each consumer depends on the trophic level below it for energy.

Symbiosis – 2 species living in a close long term relationship

• Parasitism – one specie lives in or on another specie and harms it

• Commensalism – one specie benefits and the other is neither benefited nor harmed

• Mutualism – both species are benefitted

• Predation - one specie consumes the other

Cell membrane Structure

• ____________- made of two layers

• ________ - the part of the cell membrane that is water fearing

• ________ - the part of the cell membrane that is water loving

• _________________ model – means that there are proteins in the cell membrane that help with transport of substances

Phospholipid bilayer

hydrophobic

hydrophilic

Fluid mosaic model

Cell Membrane Function• ___________- transport of substances through the

membrane without using energy2 types:

1. ______ - movement of solute2. ______ - movement of water

• _________ - transport of substances through the membrane that are either too big or not creating homeostasis ; requires energy

2 types: 1. ________ - brings big things in to cell

• 2. ________ - takes big things out of cell

Passive transport

diffusion

osmosis

Active transport

endocytosis

exocytosis

____________________________

• Structure: jello in the cell

• Function: holds everything in place

Cytoplasm

Nuclear Organelles__________________________

Structure: double membrane around nucleusFunction: keeps things in and out of nucleus

____________________ Structure: ball of fibers Function: produces ribosomes

____________________ Structure: molecule which contains _______ - (double strand of nucleic acids ) and proteins Function: contains all the directions to make an organism (genome)

__________________________

Structure: holes in the nuclear membrane

Function: allows large substances to pass through nuclear membrane__________________________

Structure: jello in nucleusFunction: holds nuclear

organelles in place

Nuclear Membrane

Nuclear Pores

Nucleoplasm

Nucleolus

Chromatin

DNA

Cytoplasmic Organelles__________________

Structure: membrane enclosing either food or waste or water

Function: storage of food or waste or water

________________ Structure: combination of ________ (single strand of nucleic acid) and other proteins; found either floating freely or attached to other organelles Function: make _________ from the directions found in DNA

Vacuole/Vesicle Ribosome

RNA

proteins

Cytoplasmic Organelles continued_______________________________

Structure: bean shaped organelles with two membranes; contain matrix (fluid) and cristae (folds in inner layer)

Function: cellular ______________________

_______________________________________

Structure: system of membranes throughout the cell; rough (contain ribosomes) and smooth

Function: RER – transports _________________, SER – transports __________ and ______________

Mitochondria

respiration

Endoplasmic Reticulum

proteinslipids fats

Cytoplasmic Organelles continued

____________

Structure: flat membrane sacs

Function: package molecules to be moved to other parts of the cell

_________

Structure: membrane sacs formed from the membranes of other organelles

Function: store food and water

_______________

Structure: sacs with enzymes

Function: help the cell digest large molecules so it can use them

Golgi Apparatus Vacuoles Lysosome

________________________ – organelles that help the cell in movement

1. _______________________________

Structure: fibers made of ball shaped protein called actin connected in long strings

Function: move the whole cell around

2. ________________________________

Structure: long, string like proteins that coil together like rope to form rods

Function: add strength to the shape of the cell

3. ___________________________________

Structure: ball shaped proteins called tubulin that come together to form a hollow tube

Function: supports the cell’s shape; used to move organelles around

May extend out of the cell membrane and form:

a. _______________________ – small hair like structures made of microtubules; aid in movement of some cells

b. ________________________ – long, tail like structures made of microtubules; aid in movement of some cells

Cytoskeleton

microfilaments

Intermediate filaments

microtubules

cilia

flagella

Cytoplasmic Organelles Only in Plant Cells

Cell wallStructure: only in __________ cells; made of complex carbohydrate called cellulose; contain plasmodesmata (openings to communicate with other plant cells)Function: makes the cell firm

Central vacuole Structure: large central vacuoleFunction: storage of __________________

________________________Structure: contain chlorophyll•Contain ________________ (fluid in inner membrane where photosynthesis takes place)•Contain _______________ (membrane sacs that contain chlorophyll in stroma)•______________________ (stacks of thylakoids inside chloroplasts)Function: trap energy by absorbing it from sunlight; photosynthesis

plant

water

Chloroplasts

stroma

thylakoids

grana

Robert Hooke• 1665• looked at cork • found that the interior of

cork is made of an ordered collection of little boxes that he called cells

• First person to use the word “cell”

Anton von Leeuwenhoek

• 1675

• first person to view living cells under a microscope

• “animalcules”

The Cell Theory•Developed in the 1800s

•Developed by: Schleiden, Schwann and Virchow

•3 parts to the Cell Theory:1. All living things are made of cells.

2. Cells are the basic units of structure and function in living things.

3. Cells only come from already present cells.

Prokaryotic cells

• have only one membrane that separates the cell from the outside world

• everything else floats freely inside the cell

• Ex: bacteria

• reproduce using binary fission - reproduction in which a bacterial cell divides into two cells that look the same as the original cell

Eukaryotic Cells

• organisms with several internal structures that are surrounded by a membrane, including the nucleus

• Ex. Plants, animals, fungi, protists

HOMEOSTASIS =

ISOTONIC =

EQUILIBRIUMbiological balance with the cell’s surrounding

environment; the amounts of molecules inside and outside the cell are kept at certain levels to maintain

a balance.

___________________________________

– a membrane that allows some molecules to pass but blocks other molecules from coming through

Semi-Permeable Membrane

Concentration Gradient

• a difference in the concentration of a substance across a membrane; forms when different concentrations of a molecule are on either side of a membrane. Cells use this to direct some of their activities.

• ________________________ – a dissolved substance

Solute

HYPOTONIC – the area (inside or outside the cell)

that has a LOWER concentration of solute

HYPERTONIC – the area that has a HIGHER

concentration of solute

________________________ – a group of cells that are similar and work together

Ex. – epithelial cells make up skin; nerve cells make up nervous tissue; muscle cells make up muscle tissue

________________________ – a group of different tissues that work together to perform specific functions

Ex. – heart, muscle, brain

________________________ – a group of organs that work together to perform specific connected tasks

Ex. Skeletal, circulatory, muscular, male repro, female repro, integumentary, nervous, endocrine, excretory, digestive, immune

________________________ – a group of organ systems

Tissue

Organ

Organ System

Organism

Stoma - openings on the bottoms of

leaves through which gases enter

or exit

fermentation

Anaerobic process of

breaking down food into CO2

What type of fermentation

occurs in human muscles?Lactic acid

fermentation

What type of fermentation

produces yogurt?

Lactic acid

What type of fermentation

produces bread?

alcohol

Where is potential energy stored?

In chemical bonds of ATP

and food

The kind of energy that is energy in

motionKinetic energy

What does ATP stand for?

adenosine tri-phosphate

Mitosis• The part of a cell’s life cycle when the cell divides it nuclear contents into 2 nuclei which are identical

•Mitosis consists of 4 steps:

•Prophase

•Metaphase

•Anaphase

•Telophase

Cytokinesis

• The part of a cell’s life cycle when the cytoplasm divides into 2 cells which are identical

DIPLOID

• Body cells are all diploid

• They contain chromosomes in PAIRS

HAPLOID

• A haploid cell has ½ the normal number of chromosomes

• Only contains ONE chromosome from each pair

• Sex cells = egg and sperm

Somatic cell = body cellgamete = sex cells

Meiosis

Formation of 4 haploid/sex cells

Gregor Mendel Lived from July 20, 1822 – January 6, 1884) Austrian monk Worked in monastery garden Used pea plants to show that the inheritance

of traits follows particular laws, which were later named after him

Trait – a characteristic of an organism

Heredity – the study of how traits are passed from parents to offspring

True breeding plants – have offspring that always show the same form of the trait

Cross fertilization – a process in which one plant fertilizes the egg in a flower of a different plant

Pollen – tiny grains containing sperm; the male plant gamete

Hybrids – the offspring of two different true breeding plants

Monohybrid cross – a cross between two organisms that differ in only one trait

Dihybrid cross – a cross between two organisms that differ in 2 traits

Mendel’s conclusions:

Gene – the factor that controls traits

Allele – the possibilities of a gene (e.g. A or a)

Simple dominance – one allele is dominant to a recessive allele

Mendel VocabularyDominant – the allele that masks any other allele

when there are 2 alleles present (A in Aa) (symbolized by the first letter in the dominant trait’s

name, always capital)

Recessive – the allele that is masked by another allele (a in Aa) (symbolized by the first letter in the

dominant trait’s name, always lower case)

Homozygous – having two identical alleles for a trait (AA or aa) (Mendel called this “true-breeding”)

Homozygous dominant – having two dominant alleles for a trait (AA) (Mendel called this “true breeding dominant”)

Homozygous recessive – having two recessive alleles for a trait (aa) (Mendel called this “true breeding recessive”)

Heterozygous – having two different alleles for a trait (Aa)

More Mendel Vocabulary

 

Phenotype – the visible traits of an organism (e.g. long or

short)

Genotype – the alleles that an organism carries (e.g. Aa or

AA or aa)

Punnett square – a model used to represent crosses between

organisms

Example: What are the possible offspring of a cross between a homozygous dominant green plant (GG) and a homozygous recessive green plant (gg)?

Frederick Griffith• 1928• How do bacteria make

people sick?• Injected mice with

bacteria. Mice died.• Injected mice with

heat-killed bacteria. Mice lived.

• Conclusion:– Something in cells

causes disease.

– He called it the ‘transforming principle’

Oswald Avery• 1944• Identified all the molecules in

the bacteria that caused disease in Griffith’s experiments

• Injected mice with bacteria – each group of mice received different molecules from the original bacteria.

• The mice that received the DNA died. The mice that received the other molecules didn’t die.

• Conclusion:– DNA stores and transmits the

information in a cell.

1950sRosalind Franklin and Maurice Wilkins took x-ray

photographs of DNA

1953

James Watson and Francis Crick determine that DNA is a double helix

The Sides of the Ladder are made up of millions of alternating sugars

and phosphates.Sugar

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Phosphate

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• The sugar is named deoxyribose.

• The two sides of the ladder are held together by rungs attached to the sugars.

Sugar

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Phosphate

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Phosphate

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Rungs of ladder – each rung contains 2 bases

•Bases contain nitrogen so we call them nitrogenous bases• The 2 bases of each rung are connected by a hydrogen bond•There are 4 bases to choose from:

AdenineThymineGuanineCytosine

Complementary Base Pairing

Adenine always pairs with thymine. Guanine always pairs with cytosine.

Thymine always pairs with adenine.

Cytosine always pairs with guanine.

So, if you know ONE side of the DNA, you should be able to figure

out the other!

What is a nucleotide?

A nucleotide is a small piece of DNA which contains:

•1 base

•1 sugar

•1 phosphate

Lots of nucleotides link up together to make a big DNA molecule.

DNA Replication• Process in which DNA makes an exact copy of

itself

• Occurs during __________________________Interphase before Mitosis

1. When it is time to replicate, the DNA unzips (at the hydrogen bonds)

2. New complementary nucleotides move in to match BOTH halves of the DNA and form hydrogen bonds with the old nucleotides.

3. Product: 2 identical DNA molecules!

Steps of DNA Replication

How genes work

Genes carry the instructions for making proteins.

Whenever a cell needs a particular protein, that gene is triggered to make a protein.

There are 2 steps to making a protein:

1.Transcription – the gene for the protein that you want is copied in the nucleus so that the original DNA never has to leave the nucleus. The copy goes to the ribosome.

2.Translation – the copy of the gene is used by the ribosome to make a protein

Codon = 3 letters on mRNA

Anticodon = 3 complementary letters on tRNA (transfer RNA)

The anticodon on tRNA matches up with the codon on mRNA and brings with it the amino acid that the codon codes for!

Peptide Bond = bond that connects 2 amino acids

• As the tRNA’s bring amino acids to the ribosome, the amino acids connect to each other with peptide bonds.

• Many amino acids connected together makes a protein.

Mutations• Mistakes in the sequence of DNA• 3 types of mutations:

–Substitution – one base is changed–Deletion – one base is left out–Insertion – an extra base is added

Taxonomy • The science of classifying

organisms and assigning each organism a name

Aristotle•4th century BC

•Greek

•2 groups – plants and animals

•He divided the category of animals according to how they moved (swimming, walking, flying)

Carolus Linnaeus•18th century

•Swedish

•2 groups – plants and animals

•he divided the animal group according to similarities in form (e.g. bats with mammals, not birds)

•Binomial nomenclature

Binomial Nomenclature• Developed by Carolus Linnaeus

• Each species is assigned a two part scientific name which is always written in italics. The 1st word is always capitalized, the 2nd word is always lower case.

• Ex: Homo sapiens and Homo neanderthalis

Genus – group of closely related species

Species – group of similar organisms that can breed and produce fertile offspring

Eubacteria and Archaea

• Bacteria• unicelluluar• may be

heterotrophic or autotrophic

• Do not have subcellular organelles

Protists• Unicellular• Autotrophic and

heterotrophic• Euglena• Paramecium• Amoeba• Have subcellular

organelles

Fungi• Yeast

(unicellular)• Mold (multi)• Mildew (multi)• Mushrooms

(multi)• heterotrophic

Plantae• Algae• Ferns• Flowering

Plants• Autotrophic• Multicellular

Animalia• Multicelluluar

• heterotrophic

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