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Flashcards in Membrane Transport PPT Deck (45)
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1
Q

all materials must pass through the ___ to enter or exit the cell

A

plasma membrane

2
Q

plasma membrane is ___

A

semi-permeable

3
Q

List 3 ways to transport molecules.

A
  1. diffusion through the membrane
  2. protein transport
  3. vesicular transport
4
Q

Transport mechanisms are categorized as either ___ or ___ processes.

A

passive,

active

5
Q

Molecules are in ___ random motion.

A

constant

6
Q

Molecules are more likely to interact when there is a ___ concentration.

A

high

7
Q

difference in the number of molecules between two regions

A

concentration gradient

8
Q

Which way will molecules move with a gradient?

A

from higher to lower concentration

9
Q

What is molecule movement driven by?

A

energy in each molecule

10
Q

the net movement of molecules down a concentration gradient; not affected by the concentration gradient of other molecules

A

diffusion

11
Q

List 4 factors that affect the rate of diffusion.

A
  1. steepness of concentration gradient
  2. temperature
  3. molecule siz
  4. nature (wind speed/ water currents)
12
Q

a result of diffusion; the energy of the molecules becomes equal; the molecules continue to move randomly but there is an equal amount of movement in both direction

A

equilibrium

13
Q

What can diffuse through the plasma membrane?

A

small, non-polar molecules;

lipids

14
Q

What is the most common substance to pass through the plasma membrane?

A

water

15
Q

Water can pass through specific water channels in the plasma membrane called ___.

A

aquaporins

16
Q

name for water diffusion

A

osmosis

17
Q

occurs when water concentration is different on the two sides of a membrane

A

osmosis

18
Q

Osmosis is dependent on the concentration of other molecules dissolved in the solution called ___.

A

solutes

19
Q

more solutes = less ___

A

water

20
Q

the concentration of all molecules dissolved in a solution

A

osmolarity

21
Q

ability of a solution to alter the cell’s water volume

A

tonicity

22
Q

solution with a higher solute concentration (less water)

A

hypertonic

23
Q

solution with a lower solute concentration (more water)

A

hypotonic

24
Q

when two solutions have the same solute concentration

A

isotonic

25
Q

Water moves from a ___ solution to a ___ solution.

A

hypotonic,
hypertonic;
(high to low concentration)

26
Q

If the cell’s fluids are isotonic to the external environment, then ___.

A

there is no change in cell volume

27
Q

If the environment is hypertonic, cells with ___. Why?

A

shrivel,

too much water diffusing out of the cell

28
Q

If the environment is hypotonic, cells will ___. Why?

A

burst,

too much water diffusing into the cell

29
Q

How do large molecules get through the plasma membrane?

A

transport proteins

30
Q

transmembrane proteins that act as channels or pores to pass molecules into or out of the cell; each protein will only transport a certain type of molecule

A

transport proteins

31
Q

List the 2 types of protein transport.

A
  1. facilitated diffusion (carrier/channel)

2. active transport

32
Q

type of protein transport in which the transmembrane protein will only transport a particular molecule; molecule binds to the protein and is released on the other side of the membrane

A

facilitated diffusion: carrier

33
Q

What does the direction of molecule movement depend on in facilitated diffusion?

A

the concentration gradient;

molecules move from high to low concentration

34
Q

type of protein transport in which the protein is an “open door”; allows molecules to move in both directions depending on the concentration gradient; usually equalized the concentration

A

facilitated diffusion: channel

35
Q

type of protein transport which requires energy from ATP; goes against the concentration gradient (low to high concentration)

A

active transport

36
Q

example of active transport

A

sodium-potassium pump

37
Q

pumps sodium (Na) out of the cell and potassium (K) into the cell; creates a source of potential energy to do work; expels 3 Na⁺ for 2 K⁺ taken in

A

sodium-potassium pump

38
Q

used for bulk transport; move many molecules or single macromolecules into or out of the cell at one time; occurs through vesicles; requires cellular energy (e.g. ATP)

A

vesicular transport

39
Q

transport into, across, and then out of cell

A

transcytosis

40
Q

transport from one area or organelle in cell to another

A

vesicular trafficking

41
Q

vesicle pinches off of the plasma membrane and transports materials into the cell

A

endocytosis

42
Q

vesicle forms inside the cell and fuses with the plasma membrane releasing the contents outside

A

exocytosis

43
Q

“cell eating”; the material taken up is made up of particles

A

phagocytosis

44
Q

“cell drinking”; the material taken up is a liquid

A

pinocytosis

45
Q

allows transport of select molecules; molecules bind to specific sites on the plasma membrane; once molecules are in sites the plasma membrane forms a vesicle around them

A

receptor-mediated endocytosis