homeostasis and control

Question 1

what is the CNS?

Answer 1

CENTRAL NERVOUS SYSTEM
- Brain
- Spinal cord

Question 2

what is the PNS?

Answer 2

PERIPHERAL NERVOUS SYSTEM
- Nerves to and from the brain and spinal cord

Question 3

Nervous System?

Answer 3

enables detections of surroundings and coordinates behaviour

Question 4

stages of nervous system?

Answer 4

• receptor
• nerve cells
• sensory neurone
• CNS (relay neurone)
• motor neurone
• effector

Question 5

neurones?

Answer 5

specialised for transmitting electrical impulses (messages) around the body

Question 6

transmission?

Answer 6

electrical impulses travel quickly.
- fatty layer- Myelin sheath acts as insulator which speeds transmission up
- not continuous
- allows nerve impulses to ‘jump’ from one gap to the next, again increasing speed

Question 7

endocrine system?

Answer 7

control system in the body that communicates using chemical messengers or hormones to produce slow but lasting responses

Question 8

the master gland?

Answer 8

pituitary gland

Question 9

where is the pituitary gland based and what does it do?

Answer 9

• at the base of brain
• secretes hormones

Question 10

direct effect?

Answer 10

• directly targets organs

Question 11

indirect effect?

Answer 11

• cause other glands to secret hormones (testosterone and oestrogen)

Question 12

negative feedback?

Answer 12

regulatory process in the body where changes in the body can be reversed once they have happened

Question 13

3 homeostasis regulations?

Answer 13

• thermoregulation
• osmoregulation
• blood glucose regulation

Question 14

where is insulin produced?

Answer 14

pancreas

Question 15

what other hormone is released from pancreas as response to low glucose?

Answer 15

glucagon

Question 16

what are insulin and glucagon?

Answer 16

negative feedback

Question 17

type 1 diabetes?

Answer 17

• genetic
• insufficient glucose
• insulin isn’t being produced fast enough
• high bloody glucose levels
• body uses fats and proteins instead of

Question 18

diagnosis of type 1 diabetes?

Answer 18

4 Ts
- Tired
- Thinner
- Thirsty
- Toilet

Question 19

treatment of type 1 diabetes?

Answer 19

• insulin injections
• good and controlled diet

Question 20

type 2 diabtetes?

Answer 20

-body cells loose sensitivity- no longer respond to insulin produced by pancreas

Question 21

diagnosis of type 2 diabetes?

Answer 21

glucose tolerance test

Question 22

treatment of type 2 diabetes?

Answer 22

• carb controlled diet
• exercise regime
• obesity= risk factor

Question 23

synapse?

Answer 23

gap left between each pair of neurones, enabling them to connect and send electrical impulses (neurotransmitters)

Question 24

MRI?

Answer 24

Magnetic Resonance Imaging
- strong magnetic fields and radio waves to produce detailed images
- no ionising radiation
- safer than CT and PET scans

Question 25

Treatment for CNS disorders?

Answer 25

removal of:
- tumours
- implants
- excess fluids

Question 26

oestrogen?

Answer 26

• female reproductive hormone
• causes release of egg
• produced in ovaries

Question 27

testosterone?

Answer 27

• male reproductive hormone
• stimulates sperm production
• produced in testes

Question 28

FSH?

Answer 28

Follicle Stimulating Hormone
- causes egg to mature in ovaries

Question 29

LH?

Answer 29

Luteinising Hormone
- stimulates egg release from ovary

Question 30

oestrogen and progesterone?

Answer 30

maintains lining of uterus

Question 31

hormonal contraceptive methods?

Answer 31

• contraceptive pill
• IUDS (coil)
• Injections
• Implant
• Patch

Question 32

non hormonal contraceptive methods?

Answer 32

• condoms
• diaphragm (cap)
• spermicidal cream (toxic to sperm)

Question 33

adrenaline?

Answer 33

produced in adrenal gland
- boosts delivery of oxygen and glucose to the brain and muscles

Question 34

thyroxine?

Answer 34

produced by thyroid gland
- stimulates metabolic rate
- plays role in growth and development
- controlled by negative feedback

Question 35

steps of IVF?

Answer 35

• women gets given FSH and LH to stimulate production of more eggs than normal
• eggs are collected- woman is sedated yet conscious
• eggs mixed with fathers sperm in the lab for 16-20 hrs- monitored microscopically for fertilisation
• any embryos are allowed to develop for 5 days
• one or two embryos are selected and placed just the mothers uterus

Question 36

issues with IVF?

Answer 36

• physically and emotionally draining
• success rate is not high
• can result in multiple births- dangerous to mother and children

Question 37

vasodilation?

Answer 37

blood vessels dilate (widen) causing blood flow to increase

Question 38

vasoconstriction?

Answer 38

blood vessels constrict (narrow) so blood flow decreases

Question 39

body temp gets too high?

Answer 39

• vasodilation
• sweat
• increase heat loss through skin

Question 40

body temp gets too low?

Answer 40

• vasoconstriction
• shiver
• skeletal muscles contract to release heat

Question 41

osmoregulation?

Answer 41

• maintain water through osmosis
• water leaves body via exhalation from lungs
• water, ions and urea are lost from skin in sweat
• excess water, ions and urea are removed via kidneys in the urine

Question 42

deamination?

Answer 42

removal of amino groups- as ammonia- from excess amino acids in the liver

Question 43

deamination in liver?

Answer 43

Protein is excreted through liver
- in liver, amino acids are delaminated for form ammonia
- TOXIC so it’s converted to urea for safe excretion

Question 44

how do kidneys produce urine?

Answer 44

• produce urine through filtration of blood and selective reabsorption of useful substances