Physiology

Question 1

3 general types of body extrinsic control mechanisms?

Answer 1

Feedforward, negative feedback and positive feedback

Question 2

Normal body temperature?

Answer 2

Around 37 degrees

Question 3

Sites for monitoring body temperature?

Answer 3

Mouth, ear, anus

Question 4

2 ways the body gains heat + what effect the first example?

Answer 4

Metabolism (hormone modulated) and muscle activity

Question 5

Main way the body loses heat?

Answer 5

EMR radiation

Question 6

Features of a negative feedback system?

Answer 6

Sensor + control centre + effector

Question 7

Part of the brain responsive to cold + warmth?

Answer 7

Posterior hypothalmic centre + anterior hypothalmic centre

Question 8

Where are thermoreceptors found and where is their control centre?

Answer 8

In the skin and the hypothalamus

Question 9

Pathway of regulating a fever?

Answer 9

• Macrophages cause prostaglandin production
• Prostaglandins tell hypothalamus to reset target body temperature higher
• Body increases temperature to reach new target

Question 10

Hypothermic + hyperthermic temperature?

Answer 10

< 35 degrees + > 40 degrees

Question 11

3 types of transmembrane proteins?

Answer 11

Channels, carriers and pumps

Question 12

Channel that allows diffusion of water?

Answer 12

Aquaporin

Question 13

Docking-marker receptor function?

Answer 13

Interact with vesicles during exocytosis and endocytosis

Question 14

Name for the sugar coat of cell membrane + function?

Answer 14

Glycoclayx and protection + prevents cells from growing over eachother

Question 15

Primary vs secondary active transport function?

Answer 15

Primary needs direct energy (ATP) vs secondary uses concentration gradient via antiport/symport

Question 16

2 types of carrier mediated transport?

Answer 16

Active (primary/secondary) and facilitated

Question 17

Net diffusion = ?

Answer 17

Rate between A and B - rate between B and A

Question 18

Fick’s law of Diffusion = ?

Answer 18

Rate of diffusion is proportional to the surface area and inversely proportional to the thickness of the membrane

Question 19

Osmotic gradient?

Answer 19

Concentration of water in a solution

Question 20

Tonicity?

Answer 20

The effect a solution has on a cell volume

Question 21

3 types of tonic solution and their effects on cell volume?

Answer 21

Iso = none, hypo = increase and hyper = decrease

Question 22

Na/K-ATPase summarised function?

Answer 22

Active transporter that moves 3 Na out of cell for 2 K in

Question 23

Membrane potential Em is mainly determined by?

Answer 23

K gradient/Ek

Question 24

Ek + ENa + Em?

Answer 24

-90 mV, +60 mV and -70 mV

Question 25

What side of the cell is more negative?

Answer 25

Inside

Question 26

Intra/extracellular factors that balance +ve K and Na?

Answer 26

Intracellular anionic/-ve proteins and extracellular Cl

Question 27

How is Em maintained?

Answer 27

Na/K-ATPase + leak channels

Question 28

When do Na, Ca and K channels open?

Answer 28

-55, -40 and +10 mV

Question 29

Normal MAP + minimum MAP needed to perfuse major organs?

Answer 29

70-100 mm Hg + 60 mm Hg

Question 30

What do alpha, beta and gamma pancreatic cells release?

Answer 30

Glucagon, insulin and somatostatin

Question 31

Large molecules enter the cell by?

Answer 31

Endocytosis

Question 32

Small molecule going against concentration gradient travels by + give an example?

Answer 32

Active transport (primary or secondary) + Na/K ATPase

Question 33

2 types of secondary active transport?

Answer 33

Antiport and symport