10-291. Sit with your test group:

Version A = front left corner

Version B = front right corner

Version C = back right corner

Version D = back left corner

11-11. What is inside a cell (anything that comes to mind - you don't have to be correct at this point)?

11-1Describe and interpret relationships between structure and function at various levels of biological organization.

TODAY: What is cell theory?

READ section 4.1 and answer questions #s 1-5 on page 72

The Discovery of the Cell

What is a cell?

Cell = smallest unit that can carry out all the processes of life

The Discovery of the CellCell = smallest unit that can carry out all the

processes of life Life is ORGANIZED Life responds to STIMULI

(responsiveness) Living things maintain HOMEOSTASIS Living things have a METABOLISM Living things GROW and DEVELOP Living things REPRODUCE Living things EVOLVE

The Discovery of the Cell What is the cell theory?

The cell theory states:

- All living things are made up of cells.

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

- New cells are produced from existing cells.

Development of Cell Theory Mid-1600s scientists began to use microscopes to observe living things.

In 1665, Englishman Robert Hooke used an early compound microscope to look at a nonliving thin slice of cork, a plant material.

Under the microscope, cork seemed to be made of thousands of tiny, empty chambers that Hooke called “cells”. The term cell is used in biology to this day.

In Holland, Anton van Leeuwenhoek examined pond water and other things, including a sample taken from a human mouth. He drew the organisms he saw in the mouth—which today we call bacteria.

Development of Cell Theory

Soon after Leeuwenhoek, observations made by other scientists made it clear that cells were the basic units of life.

In 1838, German botanist Matthias Schleiden concluded that all plants are made of cells.

The next year, German biologist Theodor Schwann stated that all animals were made of cells.

Development of Cell Theory

In 1855, German physician Rudolf Virchow concluded that new cells could be produced only from the division of existing cells, confirming a suggestion made by German Lorenz Oken 50 years earlier.

Development of Cell Theory

These discoveries are summarized in the cell theory, a fundamental concept of biology.

The cell theory states:1. All living things are made up of cells.

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

3. New cells are produced from existing cells.

Development of Cell Theory

READ section 4.2 and answer questions #s 1-6 on page 83

Owl Book Assignment

Exploring the Cell

How do microscopes work?

Most microscopes use lenses to magnify the image of an object by focusing light or electrons.

Light Microscopes and Cell Stains

A typical light microscope allows light to pass through a specimen and uses two lenses to form an image.

The first set of lenses, located just above the specimen, produces an enlarged image of the specimen.

The second set of lenses magnifies this image still further.

Because light waves are diffracted, or scattered, as they pass through matter, light microscopes can produce clear images of objects only to a magnification of about 1000 times.

Light Microscopes and Cell Stains

Another problem with light microscopy is that most living cells are nearly transparent, making it difficult to see the structures within them.

Using chemical stains or dyes can usually solve this problem. Some of these stains are so specific that they reveal only compounds or structures within the cell.

Light Microscopes and Cell Stains

Some dyes give off light of a particular color when viewed under specific wavelengths of light, a property called fluorescence.

Fluorescent dyes can be attached to specific molecules and can then be made visible using a special fluorescence microscope.

Fluorescence microscopy makes it possible to see and identify the locations of these molecules, and even to watch them move about in a living cell.

Electron Microscopes

Light microscopes can be used to see cells and cell structures as small as 1 millionth of a meter. To study something smaller than that, scientists need to use electron microscopes.

Electron microscopes use beams of electrons, not light, that are focused by magnetic fields.

Electron microscopes offer much higher resolution than light microscopes.

There are two major types of electron microscopes: transmission and scanning.

Electron Microscopes

Transmission electron microscopes make it possible to explore cell structures and large protein molecules.

Because beams of electrons can only pass through thin samples, cells and tissues must be cut first into ultra thin slices before they can be examined under a transmission electron microscope.

Transmission electron microscopes produce flat, two-dimensional images.

Electron Microscopes

In scanning electron microscopes, a pencil-like beam of electrons is scanned over the surface of a specimen.

Because the image is of the surface, specimens viewed under a scanning electron microscope do not have to be cut into thin slices to be seen.

Scanning electron microscopes produce three-dimensional images of the specimen’s surface.

Electron Microscopes

Because electrons are easily scattered by molecules in the air, samples examined in both types of electron microscopes must be placed in a vacuum in order to be studied.

Researchers chemically preserve their samples first and then carefully remove all of the water before placing them in the microscope.

This means that electron microscopy can be used to examine only nonliving cells and tissues.

Prokaryotes and Eukaryotes

How are prokaryotic and eukaryotic cells different?

Prokaryotes and Eukaryotes

How are prokaryotic and eukaryotic cells different?

Prokaryotic cells do not separate their genetic material within a nucleus.

In eukaryotic cells, the nucleus separates the genetic material from the rest of the cell.

Prokaryotes and Eukaryotes

Although typical cells range from 5 to 50 micrometers in diameter, the smallest Mycoplasma bacteria are only 0.2 micrometers across, so small that they are difficult to see under even the best light microscopes.

In contrast, the giant amoeba Chaos chaos may be 1000 micrometers in diameter, large enough to be seen with the unaided eye as a tiny speck in pond water.

Despite their differences, all cells contain the molecule that carries biological information—DNA.

In addition, all cells are surrounded by a thin, flexible barrier called a cell membrane.

Prokaryotes and Eukaryotes

Cells fall into two broad categories, depending on whether they contain a nucleus.

The nucleus is a large membrane-enclosed structure that contains the cell’s genetic material in the form of DNA. The nucleus controls many of the cell’s activities.

Prokaryotes and Eukaryotes

Eukaryotes are cells that enclose their DNA in nuclei.

Prokaryotes are cells that do not enclose DNA in nuclei.

Prokaryotic cells are generally smaller and simpler than eukaryotic cells.

Despite their simplicity, prokaryotes grow, reproduce, and respond to the environment, and some can even move by gliding along surfaces or swimming through liquids.

The organisms we call bacteria are prokaryotes.

Prokaryotes

Eukaryotes

Eukaryotic cells are generally larger and more complex than prokaryotic cells.

Most eukaryotic cells contain dozens of structures and internal membranes. Many eukaryotes are highly specialized.

There are many types of eukaryotes: plants, animals, fungi, and organisms commonly called “protists.”

Chapter 4 - CellsChapter 4 - Cells

CellCell– Basic unit of lifeBasic unit of life

Robert Hooke (1665)Robert Hooke (1665)– Used light microscope to view cork cellsUsed light microscope to view cork cells– Named tiny boxes he saw “cells”Named tiny boxes he saw “cells”

Leeuwenhoek (1673)Leeuwenhoek (1673)– First person to observe living cellsFirst person to observe living cells– Used simple microscopeUsed simple microscope

(only one lens)(only one lens)

Warm Up 10-29

What are the three parts of the cell theory?

The Cell TheoryThe Cell Theory

Cell Theory – Three partsCell Theory – Three parts– All living organisms are composed of All living organisms are composed of

cellscells– Cells are basic unit of structure and Cells are basic unit of structure and

function in lifefunction in life– Cells only come from the reproduction of Cells only come from the reproduction of

existing cellsexisting cells

Cell DiversityCell Diversity Cell ShapeCell Shape

– Shape reflects functionShape reflects function

Function of Nerve cell?Shape?

Function ofSkin Cells?Shape?

Cell DiversityCell Diversity Cell SizeCell Size– Cells vary in sizeCells vary in size

Nerve cells in giraffe neck vs. Human egg Nerve cells in giraffe neck vs. Human egg cell - size of a .cell - size of a .

– Cell size is limited by it’s surface area to Cell size is limited by it’s surface area to volume ratiovolume ratio

What this means…What this means… Volume increases faster than SA as a Volume increases faster than SA as a

cell growscell grows– PROBLEM:PROBLEM:

needed materials can’tneeded materials can’tget in fast enough get in fast enough (O2, glucose) and (O2, glucose) and wastes out fast wastes out fast enough (CO2)enough (CO2)

Notice SA increasedNotice SA increasedonly 25 times and theonly 25 times and thevolume increasevolume increase125 times125 times

Warm UP 10-30

What is the main factor limiting cell size?

Today:– Continue working on your cell organelle

research– Think about the most efficient way to

complete the research

Warm Up 11-02

What is the function of the nucleus of the cell?

Today:– Continue working on your PowerPoint

projects– You should NOT be just copying and pasting

information into your projects – if you don’t understand what your pasting in, you won’t understand the function of the organelle and you won’t pass your test…

Warm Up 11-04

What is the function of the phospholipid bilayer?

Today: – Last day to complete your assignments– Tomorrow – review the organelle

function– Friday – Quiz on the organelles

Cell Organelle PowerPoint – Cell Organelle PowerPoint – Directions – 35 pointsDirections – 35 points

You are going to create a PowerPoint that You are going to create a PowerPoint that illustrates information about illustrates information about eacheach cellular cellular organelle. organelle.

Each organelle must be identified with an Each organelle must be identified with an imageimage and you must explain it’s and you must explain it’s functionfunction..

You must also identify plant organelles and You must also identify plant organelles and compare / contrast compare / contrast the differences they have the differences they have from animal cells.from animal cells.

Your PowerPoint will be graded for the detail of Your PowerPoint will be graded for the detail of it’s information and pertinence of it’s imagesit’s information and pertinence of it’s images

You will submit your presentation to me (using a You will submit your presentation to me (using a flash drive) or you can post it to the wikispace.flash drive) or you can post it to the wikispace.

Describe and find an illustration of these Describe and find an illustration of these 25 organelles25 organelles

Plasma membranePlasma membrane– Phospholipids bilayerPhospholipids bilayer

CytoplasmCytoplasm CytosolCytosol NucleusNucleus

– Nuclear PoreNuclear Pore– Nuclear MembraneNuclear Membrane– NucleolusNucleolus

ChromosomeChromosome Nuclear envelopeNuclear envelope RibosomeRibosome MitochondrionMitochondrion Endoplasmic reticulumEndoplasmic reticulum Golgi Apparatus Golgi Apparatus LysosomeLysosome

CytoskeletonCytoskeleton MicrotubuleMicrotubule MicrofilamentMicrofilament CiliumCilium FlagellumFlagellum Centriole Centriole Cell wallCell wall Central vacuoleCentral vacuole PlastidPlastid ChloroplastChloroplast ChlorophyllChlorophyll

Warm UP 11-05

Today:– Get your laptops – open your cell

powerpoints– I will be going over the various

organelles to review and to make sure you have the correct information

– We will have a quiz on the organelles tomorrow

Warm Up 11-05

Get your laptop and get your project opened

Today:– We will be briefly going over ALL the

organelles in preparation for your quiz tomorrow

Warm Up 11-06

Today QUIZ on organelles – review your

notes Turn your projects in

Warm Up 11-9

What are three functions of the phospholipids membrane?

Read the information and then answer the questions on page #14 and #15 of the worksheet packet.

Warm Up 11-10

What is the idea behind the endosymbiosis theory?

Read and complete page 16 in the worksheet packet

Cell Organelle Review

Plant Cell

OrganellesOrganelles Plasma membrane Plasma membrane – Made of two layers of phospholipids Made of two layers of phospholipids

(a bilayer) (a bilayer) – Allows transport of molecule into / Allows transport of molecule into /

out of the cellout of the cell– Helps protect cell from bacteria, etcHelps protect cell from bacteria, etc– Chemical communication with other Chemical communication with other

cellscells (Review) (Review) PhospholipidPhospholipid – contains – contains

hydrophobic tails and hydrophobic tails and hydrophilic headhydrophilic head

Membrane contain lipids called Membrane contain lipids called sterols (cholesterol) sterols (cholesterol) – help make membrane more firm help make membrane more firm

and prevent freezing at lower and prevent freezing at lower temperaturestemperatures

Membrane Proteins: Integral proteins –

– Proteins in the plasma membrane that are embedded or pass all the way through the membrane

– Have carbohydrate attached to act as marker or label

– Function: Communication Transporting materials into cell

Peripheral proteins – proteins found only on one side of the membrane

Fluid Mosaic Model– Idea that the phospholipids / lipds /

proteins can “flow” around each other– Plasma membrane is more of a fluid

than a solid

Cytoplasm – Cytoplasm – – part of the cell including the fluid, the part of the cell including the fluid, the

cytoskeleton and all organelles except nucleus cytoskeleton and all organelles except nucleus

Cytosol – Cytosol – – the cytoplasm that includes the ribosome's but the cytoplasm that includes the ribosome's but

not the membrane bound organelles – 20% not the membrane bound organelles – 20% proteinprotein

Nucleus – Nucleus – – control center of cell– controlled by the code in control center of cell– controlled by the code in

your DNAyour DNA Nuclear Membrane / Envelope – Nuclear Membrane / Envelope –

– double membrane that surrounds the nucleus double membrane that surrounds the nucleus Nuclear Pore – Nuclear Pore –

– protein lined holes in the nuclear membrane protein lined holes in the nuclear membrane that allow RNA to enter / leave nucleusthat allow RNA to enter / leave nucleus

Nucleolus – Nucleolus – – where DNA concentrates to create ribosomal where DNA concentrates to create ribosomal

RNA (ribosome's)RNA (ribosome's)

Chromosome – Chromosome – – DNA coils to form chromatin – chromatin coils DNA coils to form chromatin – chromatin coils

to form chromosomesto form chromosomes– Chromatin is how the cell’s genetic material is Chromatin is how the cell’s genetic material is

stored when not replicatingstored when not replicating– Chromatin coils to for chromosomes when Chromatin coils to for chromosomes when

replication is occurringreplication is occurring

Ribosome – Ribosome – – proteins that direct protein synthesisproteins that direct protein synthesis– Consist of two subunitsConsist of two subunits

Mitochondria – Mitochondria – – takes organic molecules and makes takes organic molecules and makes ATPATP

(adenosine triphosphate)(adenosine triphosphate)– Phospholipid Membrane bound organellePhospholipid Membrane bound organelle

Inner membrane has many folds for reactions Inner membrane has many folds for reactions to occur (called cristae)to occur (called cristae)

Which cells would you think have the Which cells would you think have the most mitochondria? most mitochondria? – Muscle cellsMuscle cells

Endosymbiosis - Endosymbiosis - – Idea that mitochondria were once Idea that mitochondria were once

prokaryotic organisms that were prokaryotic organisms that were incorporated into eukaryotic cellsincorporated into eukaryotic cells

– Mitochondria have their own DNA and Mitochondria have their own DNA and only reproduce from division of only reproduce from division of preexisting mitochondriapreexisting mitochondria

– Prokaryotes had protection while Prokaryotes had protection while eukaryotes got ATPeukaryotes got ATP

Endoplasmic reticulum (ER)Endoplasmic reticulum (ER)– ““intracellular highway”intracellular highway”– Has a membrane and is composed of tubes and sacsHas a membrane and is composed of tubes and sacs– Rough ER – contains ribosome'sRough ER – contains ribosome's

Thus produces proteins (some phospholipids)Thus produces proteins (some phospholipids) Proteins produced then surrounded by vesicle from the ER Proteins produced then surrounded by vesicle from the ER

and then transported around / out of celland then transported around / out of cell– Smooth ER – lack ribosome'sSmooth ER – lack ribosome's

Produce lipids and hormones in sex cells (estrogen & Produce lipids and hormones in sex cells (estrogen & testosterone)testosterone)

Golgi Apparatus Golgi Apparatus – Flattened membranes and sacsFlattened membranes and sacs– Receive vesicles from ER and modify Receive vesicles from ER and modify

them as the move through the Golgi them as the move through the Golgi (get “address labels”)(get “address labels”)

– Vesicles then are sent to various Vesicles then are sent to various locationslocations

– Create lysosomesCreate lysosomes

Vesicle – Vesicle – – Used to carry contents around, into / out Used to carry contents around, into / out

of cellof cell– Vary in typeVary in type– Spherically shapedSpherically shaped– Surrounded by a membraneSurrounded by a membrane

Lysosome – vesicle that contains digestive Lysosome – vesicle that contains digestive enzymes produced by Golgienzymes produced by Golgi– Digest organic materials, bacteria, etcDigest organic materials, bacteria, etc– Break down glycogen to get glucoseBreak down glycogen to get glucose– Cytolysis or autolysis – lysosomes release Cytolysis or autolysis – lysosomes release

enzymes to destroy the cell (old or enzymes to destroy the cell (old or malfunctioning cells)malfunctioning cells)

Cytoskeleton – Cytoskeleton – – network of thin tubes / filaments that network of thin tubes / filaments that

supports the cellsupports the cell

Microtubule – Microtubule – – hollow tubes made of protein that hold hollow tubes made of protein that hold

organelles in place and give the cell shapeorganelles in place and give the cell shape

Microfilament - Microfilament - – Smaller threads that contribute to Smaller threads that contribute to

changes in cell shapechanges in cell shape– Made of proteinMade of protein

Intermediate filaments – Intermediate filaments – – Rods that anchor nucleus and other Rods that anchor nucleus and other

organelles in placeorganelles in place– Maintain internal shape of the nucleusMaintain internal shape of the nucleus– Make up most of your hairMake up most of your hair

Cilium – Cilium – – Hair like structures that extend from the Hair like structures that extend from the

surface of cellssurface of cells– Assist in cell movementAssist in cell movement– Very numerousVery numerous

FlagellumFlagellum– Whip like structure that assist in Whip like structure that assist in

movementmovement– Usually less in numberUsually less in number

Centriole – Centriole – – short cylinders that organize short cylinders that organize

microtubules for cell divisionmicrotubules for cell division– Not found in plant cellsNot found in plant cells

Cell wall – Cell wall – – rigid layer found outside plasma rigid layer found outside plasma

membranemembrane– Contain celluloseContain cellulose

Central vacuole – large organelle that Central vacuole – large organelle that stores water, enzymes, wastes etcstores water, enzymes, wastes etc– Take up a large amount of the plant cellTake up a large amount of the plant cell– If filled with water, how will plant stand?If filled with water, how will plant stand?

Upright – if they are lacking water, plant will Upright – if they are lacking water, plant will droopdroop

Plastid – Plastid – – plant organelles that have their own DNA and plant organelles that have their own DNA and

perform specific functionsperform specific functions Chloroplast – Chloroplast –

– plastid example – use light energy to make plastid example – use light energy to make carbohydratescarbohydrates

Thylakoids – Thylakoids – – flat membranous sacs that contain chlorophyll flat membranous sacs that contain chlorophyll

(where photosynthesis takes place)(where photosynthesis takes place) Chlorophyll –Chlorophyll –

– green pigment that absorbs light energy in green pigment that absorbs light energy in plantsplants

Endosymbiosis in plants?Endosymbiosis in plants?– Chloroplast DNA is very similar to DNA Chloroplast DNA is very similar to DNA

of some photosynthetic bacteriaof some photosynthetic bacteria– Is it possible the plant cells incorporated Is it possible the plant cells incorporated

the prokaryotic cells into their system?the prokaryotic cells into their system?

Cellular OrganizationCellular Organization OrganelleOrganelle

– Intracellular structures with specific functionsIntracellular structures with specific functions TissueTissue

– Group of similar cells with a specific funtionGroup of similar cells with a specific funtion OrganOrgan

– A groups of tissues with a particular jobA groups of tissues with a particular job Organ systemOrgan system

– A group of organs that accomplish a taskA group of organs that accomplish a task– IE: IE:

Digestive systemDigestive system Respiratory SystemRespiratory System Nervous SystemNervous System Endocrine SystemEndocrine System Cardiovascular SystemCardiovascular System

Cell TypesCell Types ProkaryoteProkaryote

– Lack membrane bound nucleus and organellesLack membrane bound nucleus and organelles– Still have DNA massStill have DNA mass– Bacteria and ArcheaBacteria and Archea

EukaryoteEukaryote– 1 or more cells1 or more cells– Have membrane bound organellesHave membrane bound organelles– Larger than prokaryotesLarger than prokaryotes

Cell TypesCell Types

Warm Up 11-11

What are two differences between prokaryotic and eukaryotic cells?

Today:– Get out your microscope packets and

get a partner (or you can work by yourself)

– Microscope practice and questions

Warm Up 11-12

What is depth of focus?

Today:– Observing cheek cell and Elodea cells

Warm Up 12-12

What is the maximum total magnification if the ocular lens is 10 x and the objective lens is 40x

Warm Up 11-17

What is the function of the ER? Today:

– Go over “Microscope Practice” lab– Finish Observing Cells - Elodea, Onion

Cell, Cheek Cell Lab MAKE SURE YOUR DRAWINGS ARE DETAILED

ENOUGH

Warm Up 11-18

Draw either a Elodea (in pen or pencil) and label the following: chloroplasts, plasma membrane, cell wall, cytoplasm

Today:– Cheek, Elodea and Onion cell labs due– Looking at living protists under the

microscopes

Warm Up 11-19

Get out worksheet packet – answer questions on pages 17 & 18.

Today:– Review how organelles look– Prepare for the test– Homework:

Finish Protist Lab Complete the pages of the worksheet packet

Warm Up 11-20

What is the function of the Golgi complex?

Today:– Prepare for test Monday – Review sheets

due Monday– Complete multiple choice on pages 21

and 23 of the new packet

Warm Up 11-23

Get out both your worksheet packets Turn in your protist lab Practice test:

– #17 – 20 we didn’t discuss, but try them anyway

– Short answer questions: Skip #24, 25 and 29.

Today 11-24

Test! Get out review sheets Get out a pencil

11-25

Check the grade sheet coming around– Are you missing anything?– Find it! Turn it in!

Missing a lab? – Today is the day to make it up

Go over tests (maybe)

Warm Up 12-01

Explain how our cells get food (make this explanation in some detail – you will see a similar question again