Info

Question 1

what does the graph look like that shows the substrate concentration changes during the course of a chemical reaction

Answer 1

high then decreases

Question 1

What is the causation of the lub dub sound in the heart

Answer 1

the ‘lub’ is the sound of the AV valves closing
the ‘dub’ is the sound of the semi lunar valves closing

Question 2

describe the process of CO2 being dissolved in red blood cells

Answer 2

diffuses into red blood cells

CO2 + H2O = carbonic acid (catalysed by carbonic acid)

carbonic acid dissociates into H+ and HCO3

haemoglobinic acid (H+ ions needed by haemoglobin and the oxyhaemoglobin unloads it O2)

HCO3- diffuse out the red blood cells

chloride shift (maintains balance of charge between red blood cells and plasma)

Question 3

explain why facilitated diffusion requires no metabollic energy

Answer 3

particles have their own kinetic energy

Question 4

B or T lymphocyte… secrete substances that kill infected cells

Answer 4

T lymphocytes

Question 5

B or t lymphocyte… undergo clonal expansion

Answer 5

both

Question 6

function of hinge region

Answer 6

flexibility

Question 7

function of constant region

Answer 7

binding to phagocytes

Question 8

function of variable region

Answer 8

binding to antigens

Question 9

describe the role of memory cells when a pathogen enters the body

Answer 9

recognise pathogen

produce a clone

form plasma cells (kill infection)

secondary response

form T cells

Question 10

describe how cytokine molecules can stimulate specific groups of B lymphocytes to divide

Answer 10

cytokine has a unique shape

cytokine binds to receptor

receptor and cytokine have a complimentary shape

clonal expansion

Question 11

rf value equation

Answer 11

distance travelled by spot
___________________________

distance travelled by solvent

Question 12

adhesion vs cohesion

Answer 12

adhesion- different molecules
cohesion- same molecules

Question 13

purines vs pyrimidines

Answer 13

purines- larger (A and G)
pyrimidines- smaller (T and C)

Question 14

what is it called when a muscle can contract without external stimulus

Answer 14

myogenetic

Question 15

where is the heartbeat initated

Answer 15

SAN

Question 16

define tidal volume

Answer 16

the volume of air inhaled or exhaled in one regular breath

Question 17

define vital capacity

Answer 17

maximum volume of air inhaled in one breath

Question 18

why does squamous epithelium make an effective gaseous exchange

Answer 18

shorter diffusion rate