lab exam: Membrane transport

Question 1

Diffusion

Answer 1

is the random movement of molecules that results in equal distribution

• always occurs down the concentration gradient
• molecules from high to low and its passive

Question 2

factors that affect diffusion rates

Answer 2

1. temp
2. concentration gradient
3. channels open
4. size of molecule

Question 3

simple diffusion

Answer 3

thru the membrane, molecules can cross the cell membrane ( ex. oxygen, carbon dioxide and lipids)
- occurs from higher to lower and is passive

Question 4

factors that affect simple diffusion

Answer 4

• surface area
• diffusion difference
• temp
• size of molecule
• thickness or membrane

Question 5

facilitated diffusion

Answer 5

passive transport using channels or carries

-passive and moves in any direction from high to low

Question 6

factors that affect facilitated diffusion rates

Answer 6

1. temp
2. gradient
3. # of transporters/ channels

Question 7

2 forces that act on an ion to determine its net force

Answer 7

• concentration gradient
• electrical force

higher the net force= faster concentration
smaller net force= slower concentration

Question 8

permeability and how it relates to diffusion

Answer 8

substance can cross the membrane

and it relates to a greater permeability= faster diffusion

Question 9

osmosis

Answer 9

simple diffusion of water across a selectively permeable membrane
- from a region of high water concentration to low water concentration
* is selectivity permeable
( restricts movements of ions, solutes and allows movement of water)

more solute= lower water concentration
loss solute= higher water concentration

Question 10

which way does water move

Answer 10

from a low solute concentration to a higher solute concentration

Question 11

what is one mole

Answer 11

osmolarity is the total number of solute particles in a solution

1. 0 molar solution (6.02x10 ^23)
   * the number or molecules is related to the # of particles

Question 12

tonicity

Answer 12

• effects the solutions on cells volume

3 types of toxicity

Question 13

isotonic solution’s

Answer 13

solution has the same osmolarity

Question 14

hypertonic solution

Answer 14

lower osmolarity, water concentration is higher in the solution

Question 15

hypotonic solution

Answer 15

solution has higher osmolairty. water concentration is lower in the solution than in the cell