unit one

Question 1

what is the function of the plasma membrane

Answer 1

provides physical seperation
exchange of substances
communication with environment

Question 2

ways of membrane transport

Answer 2

1. simple diffusion
   2.channel meditated diffusion
2. fallicated diffusion
3. active transport
4. endocytosis/ excotyosis

Question 3

factors (4) affect channel mediated diffusion

Answer 3

ions
small
hydrophilic

1. concentration gradient
2. number of channels
   3.size
3. charge (opposites attract, if surrounded by positive pull in a negative)

Question 4

long distance vs local communiaction

Answer 4

long distance communication- endocrine (chemical messengers- hormones), nervous system (neurotransmitters)

local communication-
autocrine, paracrine, gap functions

Question 5

osmosis and calculating osmolarity of a solution

Answer 5

osmosis is the net movement of water down its concentration gradient

Question 6

tonicity

Answer 6

ability of a solution to cause osmosis