NSF

Question 1

Define equilibrium potential

Answer 1

the potential at which an ions chemical driving force in one direction is equal to the electrical force driving it in the other direction and so bulk ion movement is thus in equilibrium

Question 2

what is resting membrane potential?

Answer 2

the membrane potential when a cell is at rest

Question 3

Define histology

Answer 3

the study of microscopic structures of tissues

Question 4

what is resolution?

Answer 4

it is the ability to differentiate between two points

Question 5

what are the 6 steps in tissue processing?

Answer 5

1. fixation
2. embedding
3. sectioning
4. mounting
5. de-waxing
6. staining

Question 6

what is H&E?

what colour is it?

Answer 6

haematoxylin and eosin stain

red and purplish blue

Question 7

what colour is trichrome stain?

Answer 7

red-pink and blue-green

Question 8

what is epithelial tissue?

Answer 8

tissue that covers and lines internal and external parts of the body, forming a barrier

Question 9

what are 5 features common to all epithelial tissues?

Answer 9

1. totally cellular
2. avascular (not blood supply)
3. self-regenerating (stem cells)
4. separated from other tissues by basal lamina
5. supported by underlying layer of connective tissue

Question 10

what are 2 groups epithelial cells are divided into and what do they mean?

Answer 10

simple- singular layer of cells

stratified- multiple layer of cells

Question 11

describe structure, appearance and function of: simple squamous cell

Answer 11

-flattened with large surface area

-

Question 12

List things that rate of membrane passage depends on

Answer 12

• surface area
• thickness of membrane
• concentration gradient
• membrane permeability

Question 13

list differences between channels and pumps

Answer 13

channels: all or nothing, passive down conc. gradient
pumps: graded, require require energy, set up ion gradients

Question 14

what is the difference between primary active transport, secondary active transport and facilitated diffusion, give examples

Answer 14

primary- uses energy directly from breakdown of ATP (NA and K)
secondary- uses energy and a carrier protein (Na and glucose co transport)
facilitated diffusion- doesn’t require energy, uses carrier proteins

Question 15

what happens if you keep increasing substrate concentration in carrier mediated transport?

Answer 15

the rate of transport will increase to a certain point, and then remain the same as all carriers are occupied

Question 16

2 reasons why ion gradients are important

Answer 16

they drive secondary active transport

resting membrane potential

Question 17

what is the difference between osmolarity and tonicity

Answer 17

osmolarity can be used to compare any 2 solutions whereas tonicity compares a solution and a cell
tonicity has no units as it is a comparative term

Question 18

give three properties of ion channels

Answer 18

• open and close
• sense voltage
• select between different ions

Question 19

what is endocytosis/exocytosis

Answer 19

substances are taken across in small vesicles without directly contacting the lipid bilayer- requires ATP-constitutive as it happens all the time
exo=taken out
endo=taken in