Drugs

Question 1

Define hormone

Answer 1

A chemical substance produced by a gland, transported by blood, and that alters the acitivities of organs

Question 2

Explain why deamination happens

Answer 2

Deamination occurs when excess amino acids are absorbed in the blood, these cannot be stored, NH2 is removed.

Question 3

explain process of deamination [4]

Answer 3

1) Enzymes in the liver split up the amino acid molecules
2) Carbon is turned into glycogen and stored
3) Nitrogen turned into ammonia then urea
4) Urea is dissovled into blood and it is taken to the kidney to be excreted

Question 4

Describe how lactic acid is processed

Answer 4

1) Excreted into the blood and transported into the liver
2) Where it is oxidised producing carbon dioxide and water
3) Lactic acid + Oxygen -> Carbon dioxide + water

Question 5

Explain the importance of osmoregulation to the cells

Answer 5

1) concentration of the solutions inside and outside the cells are similar
2) If tissue fluid / blood plasma was more dilute than the cells, water would move into the cells by osmosis causing cells to burst
3) If tissue fluid / blood plasma was more concentrated than the cells, water would move out of the cells causing cells to shrivel up

Question 6

why is there no protein in the filtrate

Answer 6

protein molecules are too large to leave the blood in the glomerulus during ultrafiltration

Question 7

Define tropism

Answer 7

Plant growth respond to stimulus

Question 8

Define gravitropism

Answer 8

Plant growth respond to stimulus of gravityD

Question 9

Define phototropism

Answer 9

Plant growth resond to stimulus of sunlight

Question 10

Explain the response of stems to gravity [4]

Answer 10

1) Auxin is produced in the tip
2) Moves to the lower side
3) Causes cells to elongate
4) Stem grows upwards

Question 11

explain how imulses are transported through synapse [4]

Answer 11

1) Neurotransmitters released diffuse across the cleft
2) Attached to receptors on the postsynpatic membrane
3) Triggers an impulse which travels along the postsynpatic neurone
4) Neurotransmitters are recycled or destroyed after the signal is sent

Question 12

Define involuntary action

Answer 12

A response to a stimulus without thinking, automatic and fast

Question 13

The organs of the human body are coordinated by the nervous system list one other way it can be coordinated

Answer 13

Hormones secreted into the blood to stimulate target organs

Question 14

Explain why glucose needs to be converted to glycogen for storage rather than
remaining dissolved in the blood [3]

Answer 14

1) glucose is soluble, glycogen is insoluble
2) Glucose concentration in the blood lowers water potential
3) Much larger quantity can be stored

Question 15

Explain why antibiotics, such as penicillin, kill bacteria but not viruses. [2]

Answer 15

1) Antibiotics ruptures cell walls and stop cell wall growth; virus have no cell walls
2) Antibiotics stop enzymes working, Viruses have no enzyme

Question 16

Define drug

Answer 16

A substance taken into the body that affects the chemical reactions in organs

Question 17

Why you shouldn’t just stop taking antibiotics after feeling better [2]

Answer 17

1) Not all the pathogens may be dead which means resistant pathogens may remain and continue to exists if they develop resistance
2) The disease can reappear/reinfect

Question 18

Explain how bacteria have become resistant to antibiotics and how humans can reduce the problem [6]

Answer 18

1) Mutation in bacteria causes it to have the resistance gene
2) There is variation in how bacteria can survive, the strongest one will live to reproduce due to natural selection
3) The offsprings will carry on this gene and every bacteria produces very quickly
4) Bacteria without resistance genes won’t reproduce and die out
5) Humans need to finish off a course of antibiotics to kill all bacteria
6) Only taking antibiotic when necessary

Question 19

Describe the changes that occur to the blood as it flows through the dialysis machine [3]

Answer 19

1) Urea conc decrease
2) Salt conc decreases
3) Glucose can increase, decrease, or stay the same

Question 20

Define excretion

Answer 20

the removal of the waste substances of metabolic reactions, toxic materials and substances in excess of requirements.

Question 21

Products of yeast anaerobic respiraiton

Answer 21

Carbon dioxide and alchohol

Question 22

muscle that contracts
to lower the ribcage

Answer 22

Internal intercoastal muscle

Question 23

Describe the mechanism of inspiration. [4]

Answer 23

1) External intercoastal muscles contract & internal intercoastal muscles relax
2) diaphragm contracts
3) volume of, thorax increases
4) pressure in thorax decreases ;
air flows in down a pressure gradient

Question 24

What are the receptors of light

Answer 24

Rods and cones

Question 25

Describe how rods and cones function

Answer 25

light absorbed (by a pigment) ;
rods detect low light (intensity) ;
give ‘black and white’ vision / do not detect colour ;
provide night vision / AW ;
cones detect high light (intensity) ;
cones detect colour ;
any detail, e.g. three different types of cone ;
convert light into (electrical) impulses ;
impulses sent to brain ;
via, neurones / sensory nerve / optic nerve ;

Question 26

Pancrease secrete [2]

Answer 26

Insulin
Glucagon

Question 27

Where is adrenaline secreted from

Answer 27

The kidney

Question 28

Name organ that stores glucose as glycogen.

Answer 28

Liver

Question 29

Define antibiotic

Answer 29

Antibiotics are chemical substances made by certain fungi or bacteria that affect the working of bacterial cells, either by disrupting their structure or function or by preventing them from reproducing.

Question 30

Suggest why some antibiotics are used less frequently than others [3]

Answer 30

bacteria are resistant to some antibiotic ;
ref. to selection ;
result of overuse ;
some are specific ;
some antibiotics used for rare disease(s) ;
some only used as last resort ;
have (many / unpleasant) side-effects / harmful / cause
allergy ;
too expensive ;
cannot be used on children ;
AVP ; ref. to other uses, e.g. on animals

Question 31

How the normal glucose concentration of the blood is maintained in dialysis

Answer 31

dialysing solution / dialysate, contains glucose ;
glucose / sugar, diffuses / moves ;
(until blood is) at, correct / normal, concentration ; A amount / level

Question 32

Explain the changes in urea concentration in the blood [4]

Answer 32

increase (urea) produced in liver ;
deamination ;
amino acids ;
decrease diffuses, out of blood / into dialysate;
through (dialysis) membrane ;
ref to concentration gradient / no urea in
dialysate ;

Question 33

Describe how urea is transported in the blood to the kidney

Answer 33

Dissolved in plasma

Question 34

Function of capsule

Answer 34

Collects filtrate

Question 35

Function of tubule

Answer 35

(selective) reabsorption ;
reabsorbs, water / glucose / salts / minerals / ions /
amino acid

Question 36

Function of collecting duct

Answer 36

(re)absorbs water / passes urine to pelvis or ureter ;

Question 37

Function of glomerulus

Answer 37

Filtering blood

Question 38

Functions of ribs

Answer 38

Prevent the collapse of lung due to pressure change
Can increase or decrease to change volume