Cytoskeletons in the closet & Plasma Membrrraaaiiiins Flashcards Preview

BIO1020 > Cytoskeletons in the closet & Plasma Membrrraaaiiiins > Flashcards

Flashcards in Cytoskeletons in the closet & Plasma Membrrraaaiiiins Deck (46):
1

A rich patchwork tapestry of proteins makes up the...

Cytoskeleton

2

The cytoskeleton has 2 functions:

1. Maintaining 3d shape in animals & plants (of cytoskeleton)
2. Moving things within the cell (cellular trafficking)

3

3 Types of Proteins that makeup the cytoskeleton:

Microtubules - Vesicle Highways
Actin - Maintain 3D shape
Keratin - anchor organelles

4

Of the 3 proteins, which is the largest?

Microtubules

5

5 functions of the plasma membrane:
CRACT

Transportation
Communication
Chemical Reactions
Recognition
Adhesion

6

To cross without a channel, a molecule must be __________ & ________.

Small & nonpolar

7

What do we know can cross?

O2, (CO2, H2O)

8

This crossing of the membrane is called...

Simple Diffusion

9

Movement down a concentration gradient...

Facilitated Diffusion

10

Facilitated diffusion relies on a:

Channel

11

T/F Facilitated diffusion uses ATP.

FALSE

12

Movement AGAINST a concentration gradient:

Active Transport

13

Active Transport utilizes a:

Pump

14

T/F ATP is required for Active Transport.

TRUE

15

How does the membrane communicate?

Carries chemical messages. SIGNAL TRANSDUCTION.

16

How does the membrane make chemical reactions?

Enzymes embedded in membranes

17

The membrane can recognize......

Intruders/Pathogens
Eggs & Sperm of own species

18

Two ways the cell membrane adhesions?

Cell-Adjacent Cell
Cells-Extracellular Matrix

19

The membrane is considered a _______ structure.

FLUID. Bilayer is free to migrate.

20

In addition to being fluid, the membrane acts as a:

Barrier, keeping things in or out

21

T/F The membrane has variable fluidity.

TRUE

22

Why is it considered variable?

Unsaturated fatty acids!
When saturated - tight
When unsaturated - loosey goosey

23

Cholesterol ________ fluidity.

Increases

24

In Northern climates?

Increased cholesterol, increased unsaturation.

25

In southern climates?

Increased saturated.

26

Similar to cholesterol but in bacteria cell membranes?

Hopanoids!

27

Cholesterol prevents ________ in the plasma membrane.

Extremes!

28

The passive movement of molecules or particles along a concentration gradient, or from regions of higher to regions of lower concentration.

Diffusion

29

Diffusion is dependent on....

Concentration Gradients

30

Gradients can be:

Chemical or Electric
(Most often combo of both)

31

Molecules will diffuse until they reach:

Equilibrium

32

For simple diffusion molecule must be:

Small & non-polar

33

Why can diffusion happen?

Membrane is semi-permeable

34

What one compound can't cross & no transporter for?

Sucrose!

35

Movement of a solvent through a semi-permeable membrane into a solution with higher solute concentration.

Osmosis

36

In osmosis, it always goes from ___ to ____.

Low to high

37

The total concentration of solutes =

Osmolarity

38

Low solute concentration =

High H20, Hyposmotic

39

High solute concentration =

Low H20, Hyperosmotic

40

The H20 will move...

Down its gradient from high h20 to low h20

41

The ability of a solution to cause a cell to gain or lose water.

Tonicity

42

Solute = Solute

Isotonic - Normal/Flaccid

43

Solute > Solute

Hypotonic - Lysed/Turgid

44

Solute < Solute

Hypertonic - Shrink/Plasmolyse

45

Prokaryotes have membrane bound organelles. T/F?

FALSE - just internal membranes which fold in on themselves.

46

The internal membrane is part of the plasma membrane.

TRUE - not seperate. Fold/fold/fold.