1

act as a ___________ between the cell and its environment.

________ the passage of “selected”

substances into and out of the cell.

it is __________and able to change shape.

2

3

“________”

Components of the membrane are able to move

“Mosaic”

A collage of many different proteins, lipids, and carbohydrates

4

Phospholipid

bilayer

composed mainly of phospholipids:◦

polar head (phosphate)

hydrophillic

◦

nonpolar

tails

(2 fatty acid chains)

hydrophobic

1.

Phospholipids2.

Membrane Proteins3.

Carbohydrates: Glycolipids

and Glycoproteins4.

Cholesterol

7

________ proteins (Transmembrane

proteins):Proteins that insert into the membrane.

Peripheral proteins:

Proteins attached to the surface of the cell membrane

8

Transportation

move substances across

Enzymes

carry out steps in a metabolic pathway.

__________ ________

once a chemical messenger binds, initiates a chain reaction of chemical changes in the cell.

Cell __________

hold adjacent cells together

Attachment to the cytoskeleton important in maintaining cell shape and fixes the location of certain membrane proteins.

9

Some membrane carbohydrates are covalently bonded to lipids: ____________

Most membrane carbohydrates are covalently bonded to proteins: glycoproteins

Note: “Glyco”

refers to the presence of carbohydrates

10

Cell-to-cell recognition:

◦

Allows cells to determine if other cells it encounters are similar or different from itself.

identity depends on the composition of the

carbohydrate (referred to as the surface marker)

11

12

____-fused-rings structure embedded within the membrane

Most membrane components can drift about laterally () in the plane of the membrane

At critical low temperatures, some membranes may solidify:

this causes changes in permeability;

substances may be unable to get in/out

some proteins stop working due to their

inability to move

13

At critical high temperatures, some membranes may become too fluid:

this causes changes in permeability

large gaps can form resulting in “leaks”

14

Cholesterol also enhances membrane fluidity.

It wedges in between phospholipids

hinders the close packing of them.

keeps some rigidity

15

16

Function:

To carry out the reactions of cellular respiration

CELLULAR RESPIRATION:C6

H12

O6

+ 6O2

6CO2

+ 6H2

O + Energy (ATP)

Series of reactions that make ATP, which is the form of energy that cells use in living things!

17

Appearance (Structure)

It contains two membranes:

Smooth outer membrane

Highly folded inner membrane that provides many locations for proteins that help make most ATP molecules

In the centre of the structure, there is a protein-rich fluid called the matrix

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http://micro.magnet.fsu.edu/cells/mitochondria/mitochondria.html

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Intermembrane space

Function

Carry out the reactions of photosynthesis

PHOTOSYNTHESIS:light

6CO2

+ 6H2

O C6

H12

O6

+ 6O2

Series of reactions that help make food for plants and some bacteria and protists.

The food can be stored and used as starting materials for the reactions of cellular respiration.

20

Appearance (Structure)

Contains two membranes:◦

Outer membrane◦

Inner membrane

In the centre of the structure, there are stacks of thylakoids

that contain pigments

such as chlorophyll.

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0.5 Cellular Functions 7 22

Grana (many stacks)

Make a Venn diagram comparing the differences between mitochondria and chloroplasts!

MITOCHONDRIA

CHLOROPLASTSBOTH