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RRCCPA Physiology/Pathophysiology I > Cells > Flashcards

Flashcards in Cells Deck (42)
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1
Q

Components of plasma membrane

A

membrane lipids, membrane proteins, membrane carbohydrates

2
Q

Types of lipids in the plasma membrane

A

phospholipids, cholesterol, glycolipids

3
Q

functions of the plasma membrane

A

physical barrier, selective permiability, electrochemical gradients, communication

4
Q

true or false: half of the weight of the plasma membrane is proteins

A

true

5
Q

true or false: an enzyme is a membrane protein

A

true

6
Q

passive membrane transport

A

no expenditure of energy required. substances move down concentration gradient

7
Q

active membrane transport

A

requires energy (hydrolysis of ATP) involves movement of a substance up a concentration gradient or the formation or loss of a vesicle

8
Q

substances that participate in simple diffusion

A

O2 and CO2, some fatty acids, ethanol, urea

9
Q

channel mediated diffusion

A

movement of small ions through water filled protein channels

10
Q

Carrier mediated diffusion

A

small polar molecules cross membrane with carrier proteins (down gradient)

11
Q

Primary ion responsible for establishing resting membrane potential

A

Potassium

12
Q

primary active transport

A

uses energy directly from the breakdown of ATP

13
Q

_____ K ions into the cell, while moving ____ Na ions out of the cell in the K/Na pump

A

2,3

14
Q

secondary active transport

A

uses energy from movement of the 2nd substance down its gradient.

15
Q

Symport

A

two substance moved in the same direction

16
Q

antiport

A

two substance move in opposite directions

17
Q

exocytosis and endocytosis are examples of what kind of transport

A

Vesicular

18
Q

neurotransmitters releasing from nerve cells is a great example of what?

A

exocytosis

19
Q

T/F: The cell membrane is equal parts lipid and protein (50/50) by weight.

A

True

20
Q

What 2 types of substances are able to penetrate the plasma membrane without assistance?

A

Small (O2, CO2) and non polar (H20)

21
Q

Name the 3 types of lipids found in a plasma membrane.

A

Phospholipids, Glycolipids, and cholesterol

22
Q

What are the 2 roles of cholesterol in the lipid bilayer?

A

Strengthen the membrane

Stabilize the membrane against temperature extremes

23
Q

Glycolipids are found on the inside/outside of the membrane?

A

Outside

24
Q

Glycolipids help form the sugar coating on the outside of the membrane, known as the __________.

A

Glycocalyx

25
Q

Name the 4 functions/characteristics of the plasma membrane.

A

Physical barrier
Selective permeability (regulates entry and exit of ions/nutrients, waste molecules)
Electrochemical gradient
Communication (through receptors)

26
Q

Name the type of membrane protein that is embedded within and extends across the bilateral

A

Integral protein

27
Q

Name the membrane protein that is not embedded in the bilayer and is loosely attached to the external or interior surfaces of the membrane.

A

Peripheral proteins

28
Q

Name the 6 different types of membrane proteins.

A
Transport
Receptor (for ligands)
Identity marker (communicate health and “self”)
Enzymes
Anchoring site for cytoskeleton
Cell adhesion molecule
29
Q

T/F: a transport protein is necessary for passive simple diffusion.

A

False (they go right through the membrane for simple diffusion)

30
Q

Facilitated diffusion is a passive process and can be either _______ mediated or _______ mediated.

A

Channel, Carrier

31
Q

Secondary active transport uses energy from the movement of another substance. Two examples are ________, which moves substances in the same direction, and _________, which moves two substances in opposite directions.

A

Symport and antiport

32
Q

The rate of passive diffusion of a substance down its concentration gradient is determined by what 3 things?

A

“Steepness” of concentration gradient
Temperature (Fever)
Molecular size (bigger moves slower)

33
Q

Facilitated diffusion through channels or carriers is for_______ or __________ solutes.

A

Charged, polar

34
Q

Channels are for movement of what?

A

Small ions, K+, Na+

35
Q

Channels can be leak or gated. Leak are always open. Name the two things that stimulate gated channels to open.

A

Voltage, Hormones (ligands)

36
Q

__________ mediated diffusion occurs when a substance binds and changes the protein shape, releasing substances on the other side of the membrane.

A

Carrier

37
Q

Primary active transport uses ATP. What pump have we talked about that is primary active transport?

A

Na+K+ ATPase pump

38
Q

How many of each ion, Na+ and K+ does ATPase move in/out?

A

3Na+ out, 2 K+ in

39
Q

Describe the 4 steps of the Na+/K+ pump.

A
  1. Na+ and ATP bind to pump
  2. ATP splits into ADP and Pi, protein changes conformation, moves 3 Na+ out
  3. Pi released, 2 K+ bind
  4. Pump changes conformation, 2 K+ released inside cell
40
Q

___________ involves invagination of the plasma membrane and is an active process.

A

Endocytosis/pinocytosis

41
Q

_______ uses pseudopodia to engulf and eat and is an active process.

A

Phagocytosis

42
Q

Receptor-mediated endocytosis uses a ________ coated pit.

A

Clathrin