Mills Biology 2002 Chapter 4 Cell Structure and Function Assignments Read Chapter 4 in textbook Read appropriate pages in CliffsAP

Mills Biology 2002

Chapter 4 Cell Structure and FunctionAssignments

• Read Chapter 4 in textbook• Read appropriate pages in CliffsAP

Mills Biology 2002

Chapter 4 Cell Structure and FunctionCell Trivia

• How many cells do we have in our bodies?– 75 trillion = 75 X 1012 !!! That’s a lot

• 75,000,000,000,000• Vary in size (um = 1/1000 mm)

– human egg cell 140 um– RBC 7.5 um– smooth muscle cell 20-500 um

• RBC’s made at a rate of about 1.2-2.5 million/sec. - 1/2 ton in a lifetime, produce about 1 oz. of new blood daily

• Entire stomach lining replaced every 3 days

Mills Biology 2002

Chapter 4 Cell Structure and Function

• Class periods:1-2• Topics

– 4.1 Cellular Level of Organization

– 4.2 Prokaryotic Cells– 4.3 Eukaryotic Cells

Mills Biology 2002

4.1 Cellular Level of Organization What is the Cell?

• Development of the cell theory

• Cell size • Two basic cell

types

Mills Biology 2002

What does this have to do with the cell theory?

Mediterranean Oak Tree

Mills Biology 2002

What is the Cell?Development of the cell theory

1600’s

Hooke - England

Leeuwenhoek - Holland

Mills Biology 2002

Anton van Leeuwenhoek

A Screw for adjusting height

B metal plate-body of scope

C Skewer to impale object and rotate it

D Spherical lens

Mills Biology 2002

4.1 Cellular Level of Organization Development of the cell theory

• 1800’s– Henry Dutrochet– Robert Brown– Matthies Schleiden– Theodor Schwann– Johannes Purkinje– Rudolph Virchow– Max Schultz– Felix Dujardin

*Just know that they were involved with developing the “cell

theory”

Worked like Leeuwenhoeks, but could “load” 8 specimen.

Mills Biology 2002

Mills Biology 2002

4.1 Cellular Level of Organization Development of the

cell theory


All living things are made of

cells.

Mills Biology 2002


cell theory


• Found same dense round body in plant cells as had been seen in animal cells.

• Gave it a name. What was it?– nucleus

Mills Biology 2002



cell theoryAll plants are made of cells!

Mills Biology 2002

• 1800’s– Henry Dutrochet– Robert Brown– Matthies Schleiden– Theodor

Schwann– Johannes Purkinje– Rudolph Virchow– Max Schultz– Felix Dujardin


cell theory

Animals are made of cells too!

Mills Biology 2002


cell theory• 1800’s

– Henry Dutrochet– Robert Brown– Matthies Schleiden– Theodor Schwann– Johannes

Purkinje– Rudolph Virchow– Max Schultz– Felix Dujardin Proposed unique

nature of fingerprints.

• Named the jellylike substance that filled cells. What did he name it?– protoplasm

Mills Biology 2002



cell theory

All cells arise ONLY from

preexisting cells.

Mills Biology 2002


cell theory • 1800’s

– Henry Dutrochet– Robert Brown– Matthies Schleiden– Theodor Schwann– Johannes Purkinje– Rudolph Virchow– Max Schultz– Felix Dujardin

• Proposed that protoplasm was found in cells of all types of organisms.

Mills Biology 2002


cell theory• 1800’s

– Henry Dutrochet– Robert Brown– Matthies Schleiden– Theodor Schwann– Johannes Purkinje– Rudolph Virchow– Max Schultz– Felix Dujardin

• Saw one celled organisms

Mills Biology 2002


cell theory

• What is the cell theory?– All organisms are made of one or more

cells.– Cells are the structural and functional units

of all organisms.– All cells come from pre-existing cells by self

reproduction.

– Took many years to gather this knowledge.

Mills Biology 2002


cell theory

Rabbit intestinal

cells.

Corn leaf cells.

Mills Biology 2002

4.1 Cellular Level of Organization

– Cells usually organized one of two ways:

• Unicellular and colonial organisms• Multicellular organisms

Mills Biology 2002


Unicellular and Colonial Organisms• Can carry on all life

processes• Include bacteria,

protozoa, many algae, some fungi

• Can exist as:– Single one celled entity– Simple colonies

• Organisms just “hang out” together

– Complex colonies• Organisms are

interconnected and communicate

Simple colonies

Bacteria

Complex colonies

Green algae-VolvoxSingle entity - Amoeba

Mills Biology 2002


Multicellular Organisms• Hundreds to billions of cells• Specialized cells, cannot function independently

– Cells organized into tissues– Tissues organized into organs– Organs organized into organ systems

Mills Biology 2002

4.1 Cellular Level of OrganizationTypes of Tissue

• Epithelial, Connective, Nervous, Muscle Tissue

Epithelial cells of GI tract Simple squamous epithelium lining alveoli of lungs.

Adipose (fat) tissue and bone, types of connective tissue

Muscle Tissue

Nervous tissue-neuron in gray matter of brain

Mills Biology 2002


Cell Size

Cube shape

Surface area =area of one side X the number of sides

Volume=length x width x height

• Prokaryotes 1-10 micrometers/Eukaryotes 10-100 micrometers (micrometer = 10-6 meters= 1/1000th of a meter)

• Significance of cell surface area to volume ratio

Calculate the surface area to volume ratio for a cube that is 1mm on each side.

Do the same calculation for a cube that is 3mm on each side.

Which cell would have the advantage? Why?

Calculations:

S.A. = 1mm x 1mm = 1mm2 x 6 sides = 6mm2

Volume = 1mm x1 mm x 1mm = 1mm3

Surface area/Volume ratio = 6:1

S.A. = 3mm x 3mm x 6 sides = 54mm2

Volume = 3mm x 3mm x 3mm = 27mm3

Surface area/Volume Ratio = 54:27 = 2:1

Mills Biology 2002

Mills Biology 2002


Two basic cell types• Name the two basic

cells types.• What is the

difference between them?

• What is the same?

Mills Biology 2002

4.1 Cellular Level of Organization Two basic cell types

• What type is this?

• What type are these?

First 3 billion years of life on earth – only prokaryotes. Eukaryotes only around for about 1.5 billion years.

Prokaryotic

Eukaryotic

Mills Biology 2002

4.2 Bacterial Cells• Prokaryotic – no nucleus

– Pro=before– Karyon=kernel

• Cell wall– Peptidoglycan– Sometimes surrounded by a

capsule and/or a slime layer

• Cytoplasm– Contains some organelles

• Nucleoid (not a membrane bound nucleus)

– Usually one loop of DNA– May also have smaller

accessory rings called plasmids

• Ribosomes• Photosynthetic bacteria have

thylakoids

• Flagella

Prokaryotic E.coli Movie 35 sec.Hard drive ..\..\Biology Clipart and sounds\Biology movies and animations\prokaryotic cell e coli movie.mov

Mills Biology 2002

4.2 Bacterial Cells

• Phtosynthetic bacteria– Cyanobacterium

(previously called blue-green algae)

Mills Biology 2002

These are cells from inside your body.

Which are prokaryotic?

E. Coli (stained green)

Which are eukaryotic?

White blood cell (stained red)

Mills Biology 2002

4.2 Bacterial CellsSummary

• Prokaryotic cells have three consistent features

Outer boundary Cell wallPlasma membrane

Cytoplasm RibosomesThylakoids (photosynthetic)

Nucleoid Innumerable enzymesChromosome (loop of DNA)

Mills Biology 2002

Mills Biology 2002

4.3 Eukaryotic Cells

• Cell walls• Cell membrane• Nucleus• Cytoplasm• Origins of

eukaryotic cells

• Good http://micro.magnet.fsu.edu/cells/animalcell.html

Mills Biology 2002

4.3 Eukaryotic Cells Cell Walls

• Plants (and bacterial) cells have cell walls

• Animal cells do not have cell walls• Fairly rigid-gives shape and support• Outside of cell(plasma) membrane• Holes in it, substances can pass through

Mills Biology 2002


Plant cell

Animal cell

(no cell wall)

Plant cell wall made of cellulose. Bacterial cell wall made of peptidoglycans.

Mills Biology 2002


Mills Biology 2002

4.3 Eukaryotic Cells Cell Membrane

• Also called plasma membrane• Present in prokaryotes, and eukaryotes• Separates what’s inside the cell from what’s

outside• Selectively permeable - allows things to pass

into and out of the cell-this is vital feature• Very important for maintaining homeostasis

Mills Biology 2002


What compounds make up the cell

wall?

Mills Biology 2002


Will look at more closely in next chapter

Transport proteins

Receptor proteins

Enzymatic/catalytic proteins

Mills Biology 2002


• Typical cell is fluid filled and membrane bound

• Fluid inside cell = cytoplasm

• Structures within cytoplasm = organelles

Mills Biology 2002

4.3 Eukaryotic Cells The Nucleus

• Nucleus is largest organelle

• Membrane bound-nuclear membrane – double layer

• Controls cell-without it, cell dies

• Contains nucleolus or nucleoli – center for ribosome production

• Contain DNA = chromatin = chromosomes

Prokaryote-no membrane bound nucleus, but has

nucleoid.

Mills Biology 2002

Cell StructureThe Nucleus

Mills Biology 2002

What do you see?

Liver cell nucleus(center of picture) TEM x 20,720 . Mitochondria red, ribosomes blue, ER green, nucleolus purple. David Kunkel

Mills Biology 2002

4.3 Eukaryotic Cells The Cytoplasm

• Fluid substance inside cell

• Surrounds nucleus and other organelles

• Many chemicals dissolved in it, chemical reactions can take place in it.

• Contains cytoskeleton that keeps cell organized

Mills Biology 2002

4.3 Eukaryotic Cells The Cytoplasm-Organelles

• Ribosomes– Composed of rRNA and

protein– Several thousand to a

million per cell.– Found on rough ER

(proteins for export)and free(proteins for use within cell) in cytoplasm

– Function: protein synthesis– Can produce proteins at a

rate of 2 aa/sec in eukaryotes and 20aa/sec in prokaryotes

– Prokaryotic ribosomes vary from eukaryotic and are similar to ribosomes found in mito and chloroplasts

Mills Biology 2002

Can you name these?

Ribosomes and polyribosomes in the cytoplasm of a liver cell. TEM x 173,400 . David Kunkel

Mills Biology 2002

Ribosomes made in the nucleus under the direction of DNA. Made up of protein and rRNA.

Mills Biology 2002


• Endoplasmic reticulum– Transport system for

molecules in cell– Extensive network of

interconnected, fluid filled tubes and cavities

– Two types: • rough• smooth

Rough ERcoated with ribosomes

•protein synthesis

Smooth ERno ribosomes

•lipids , steroids and fatty acid synthesis

Mills Biology 2002


Mills Biology 2002

Rough endoplasmic reticulum with ribosomes TEM x 61,560. David Kunkel

Mills Biology 2002


• Golgi Bodies– Refines, packages

and delivers proteins and lipids

– stack of flattened sacks called cisternae

– receives proteins from ER

Mills Biology 2002

Mills Biology 2002


• Lysosomes– Garbage disposals– Vesicle containing digestive

enzymes (acid hydrolases)– Produced by Golgi

apparatus– over 40 types of enzymes– Function to:

• digest bacteria, viruses, toxins

• degrade worn out cell parts• break down non useful fetal

tissue – no longer thought true (programmed cell death instead)

– Lysosomal storage diseases• Tay Sachs Disease

Tay Sachs Disease–Autosomal recessive, neurologic disorder, lipids build up on nerve cells, 1 out of 27 Jews in America carry gene, there is a test for carriers

Mills Biology 2002


• Peroxisomes– Membrane bound vesicle– Contain enzymes that can

oxidize small organic compounds, resulting in production of hydrogen peroxide

– Hydrogen peroxide broken down into oxygen and water by enzyme, catalase, also produced by peroxisome

– Common in liver and kidney cells

Mills Biology 2002


• Vacuoles– Membrane bound– Bigger than

vesicles– Store things

• food,water,pigments, toxic substances

– Contractile vacuoles

Mills Biology 2002


• Vacuoles – contractile water vacuole

Paramecium contractile vacuole

Mills Biology 2002


• Summary – Organelles of the endomembrane system– Nuclear envelope– Edoplasmic reticulum– Golgi apparatus– Lysosomes– Peroxisomes– Vacuoles

Flight through an Animal Cell Animation 39 sec.Hard drive ..\..\Biology Clipart and sounds\Biology movies and animations\animal cell journey movie.mov

Mills Biology 2002


• Mitochondria– “Powerhouse” of cell– Oval shaped, with

cristae– Produce ATP-cell

respiration– Cells that use more

energy have more– Can self replicate, have

own DNA– From mother– Originally thought to

be an invading bacteria

Mills Biology 2002

Mills Biology 2002

Mitochondria animationHard drive

..\..\Biology\Biology Clipart Movies Animations Sounds\Biology movies\mitochondria video animation.mov

Mills Biology 2002


• Plastids– Found only in photosynthetic eukaryotic

organisms – not in fungi or animals– Two types

• Leukoplasts– Colorless – store things, like starch in a potato

» amyloplast• Chromoplasts

– Contain pigments – give color– Chloroplasts most important chromoplast

» Contain green pigment chlorophyll» Contain own DNA (like mitochondria)

Mills Biology 2002


chlorophyll is here.

Leukoplast

ChromoplastMost familiar one is a

chloroplast

Mills Biology 2002

Plant cell TEMx 7260. Plastids yellow. Mitochondria red.David Kunkel

Mills Biology 2002

4.3 Eukaryotic Cells The Cytoplasm-Cytoskeleton

• Cytoskeleton– Supports and organizes– Contains three types of

elements• Microfilaments (actin

filaments)• Intermediate tubules• Microtubules

Mills Biology 2002


• Microfilaments– Long, thin rods of actin– Interact with motor

molecules, myosin– Structural and mobility

• Under plasma membrane

• In microvilli• Allow formation of

pseudopods• Aid cytokinesis

Mills Biology 2002


• Intermediate filaments– Ropelike polypeptide– Support cell and nuclear

membranes– Help in formation of cell

to cell junctions– Give mechanical

strength to skin (keratin)– Can assemble and

disassemble as needed

Mills Biology 2002


• Microtubules– Made of globular protein,

tubulin– Assembled in the

microtubule organizing center (MTOC), which in eukaryotic cells is a structure called the centrosome

– stiffer, help maintain shape– Dynamic, assemble and

disassemble– help move organelles within

cells– With help of motor

molecules kenesin and dynein

– Component of centriole, cilia and flagella

Mills Biology 2002


Mills Biology 2002


• Centrioles– Composed of microtubules– Near Golgi and nucleus– Non membranous– Most cells have 2 that lay at

right angles to each other – Centrioles made of nine

microtubule triplets• 9 + 0 pattern of

microtubules (9 triplets and zero central microtubules)

– Function to separate chromosomes during mitosis

Mills Biology 2002


• Cilia– large numbers on free

surfaces of some cells– tiny, hairlike, attached

to basal body– arranged in rows– “to and fro” motion– respiratory tract and

digestive tracts of animals

– propel other substances along cell

• Flagella– longer– usually only one per

cell– undulating, wavelike

motion propels the cell

– sperm, one celled organismBoth arise from basal body.

Both have 9 +2 microtubule pattern.(9 doublets arranged around 2 central

microtubules.)

Both made of of microtubules.

Mills Biology 2002


CILIA

Basal body has 9 triplets arranged in a circle – same as centrioles. May arise from

centrioles

Mills Biology 2002


CILIA

Mills Biology 2002


Mills Biology 2002


FLAGELLA on sperm cells

Mills Biology 2002

What is it?

Cilia cross section TEM x 199,500. Notice 9,2 arrangement. David Kunkel

Mills Biology 2002Flagella and Cilia Animation..\..\Biology\Biology Clipart Movies Animations Sounds\Biology movies\flagellum and cilia movie.swf

Mills Biology 2002

4.3 Eukaryotic Cells Origins of the Eukaryotic Cell

• Endosymbiotic theory– Endosymbiosis

• One cell lives inside another to the mutual benefit of both.

• Mitochondria and chloroplasts may have been bacteria that entered cell.

Mills Biology 2002

Mills Biology 2002

The End

Read Connecting the Concepts pg 81

Documents

Mills Biology 2002 Chapter 4 Cell Structure and Function Assignments Read Chapter 4 in textbook Read appropriate pages in CliffsAP