Notes 10-26-07: 1.4.1: Draw a diagram of the fluid mosaic model: Show bilayer, cholesterol, glycoprotein, integral and peripheral proteins. 1.4.2: Label.

Notes 10-26-07: 1.4.1: Draw a diagram of the fluid mosaic model:• Show bilayer, cholesterol, glycoprotein, integral and

peripheral proteins.

1.4.2: Label the hydrophobic and hydrophilic portions and explain how phospholipids maintain the structure of cell membranes.

Hydrophobic

hydrophilic

hydrophilic

Phospholipids have a polar ‘head’ (phosphate group) and a non-polar hydrocarbon chain. Polar likes water and is near the water. The non-polar lipid chains stay together away from the water.

(Integral protein)

Peripheral proteins are on the outside layer… just draw one…

Make sure that you are on ‘View’ and ‘Slideshow’ for the rest of the

activity

Prokaryotes do not have membrane-

bound organelles like ER, Golgi,

Mitochondria etc…

Prokaryotes

• ‘Pro’ means ‘before’

• ‘Kary’ means kernal

• Prokaryotes are cells without a nucleus!

• They are SMALL

• Example: Bacteria

Neisseria gonorrhoeae - coccoid prokaryote; causes gonorrhea

Staphylococcus aureus, a Staphylococcus prokaryote

Some prokaryotes that cause disease

Anthrax! Bacterial disease. (caused by a prokaryote)

Impetigo, common bacterial disease

Leprosy, bacterial disease

Other famous prokaryotic diseases:•Gonorrhea•Acne•Syphilis•Typhoid fever•Staph infection•Gangrene

NOT in prokaryotes! (Why?)

A cell with a golgi apparatus Prokaryotes don’t have organelles with membranes around them!

Monkey cell infected containing roughly twenty Coxiella burnetii

Why is Coxiella burnetii NOT a prokaryote?

Each cell that is infecting has a nucleus!

http://www.quia.com/mc/65947.html

Go to this site and play one of the games

Mitochondria and chloroplasts have their own DNA… (in fact it is one of the pieces of endosymbiotic theory… they originated on

their own first)

The more specialized

organelles you have, the bigger

you can be.

Plasmodesmota – channel between two cells with a cell wall. ‘Pla’ and ‘Plant’

Gap junctions, channels between cells with membranes only

Desmosome - They are like rivets that hold two cells together. Necessary to

form tissues

Tight junctions – like a sewn seam that keeps two cells together

http://nobelprize.org/educational_games/medicine/cell/

If you are up to it, play this game… look at the clues that the observers give you to know

which organelle to give to the guy going up the

ladder. The password is megacell.

Microtubules, microfilaments,

intermediate filaments and

microtrabecular lattice are part

of the cytoskeleton.

Microtubules – large, and make up cilia, centrioles, and flagella. They

are arranged in 9-2 format… 9 ‘doublets’ surrounding a pair.

Microfilaments

• Small strings of globular protein.

• Used especially in cell division. (cleavage furrow)

Peroxisomes-sacs of enzymes that come out of the smooth endoplasmic reticulum. They are used to

detoxify things by adding oxygen to them. Different from lysosomes – lysosomes have digestive enzymes

to break down food and old cell parts.

Glycoproteins and glycolipids are used in cell recognition.

Phagocytosis: endocytosis where the

membrane wraps around the

desired material and ‘eats’ it. Phago=eat

Pinocytosis: endocytosis

where the cell ‘drinks’.

Pino=drink

Cotransport proteins:

Bravo! Biologia!

Beisbol y biologia !

Dynein arms- ‘motors’ that cause the doublets to pull

together. When they turn off and on it makes the cilia or

flagella move.

Surface to Volume ratio: When you look at the following, notice that as volume increases, surface area doesn’t increase as much…

Surface to volume with m and m’s

Diameter (in mm)

Radius(1/2 diameter)

Surface Area:(4r2)

Volume:(4r3)

Ratio:S.A./Volume

Mini m&m’s

4mm

Regular m&m’s

8mm

Peanut m&m’s

10mm

Questions regarding Surface:Volume

1. Describe how increasing the size of a cell affects the ratio of Surface area to Volume ratio.

2. Describe how increasing the size of a cell affects the ability of the cell to diffuse products into and out of the cell.

3. Why is smaller better for diffusion?

                                This scanning electron microscope picture demonstratesHIV budding (arrows) from the surface of an infected

T-lymphocyte magnified 80,000X.