animal coordination, control and homeostasis

Question 1

what does the endocrine system do?

Answer 1

it sends hormones around the body

Question 2

what are the 5 different glands and what do they do?

Answer 2

• pituitary gland: release hormones into the blood, the master gland
• pancreas: produces and releases insulin, controls blood glucose levels
• thyroid gland: produces and releases thyroxine, controls metabolic rate, heart rate and temperature
• adrenal gland: produces and releases adrenaline, involved in the fight or flight response
• ovary: produces and releases oestrogen, involved in the menstrual cycle

Question 3

what 3 things does the flight or flight response result in?

Answer 3

• increase heart rate/blood pressure: more oxygen to reach muscles quickly
• increase blood flow to muscles: more blood reaching the muscles so they can contract with greater strength and quicker
• increase blood sugar levels: break down glycogen to glucose which muscles use to contract

Question 4

what do low levels of thyroxine lead to?

Answer 4

stimulates the production of TRH in the hypothalamus, this causes the release of TSH from the pituitary gland which acts on the thyroid to produce thyroxine, and when the thyroxine levels reach the normal level it stops the production of TSH

Question 5

what is the menstrual cycle?

Answer 5

the process that the body undergoes each month to prepare for pregnancy

Question 6

what is the process of the menstrual cycle?

Answer 6

day 1-4, the lining of the uterus breaks down
day 3, the egg starts to matter due to high levels of FSH
day 4-15, the lining of the uterus thickens due to high levels of oestrogen
day 15-28, the lining of the uterus stays thick due to high levels of progesterone
day 28, the lining of the uterus breaks down due to low levels of progesterone

Question 7

what are the 4 hormones involved in the menstrual cycle and what do they do?

Answer 7

• FSH: causes the egg to mature
• LH: causes the egg to be released
• oestrogen: causes the lining of the uterus to thicken
• progesterone: causes the lining of the uterus to stay thick

Question 8

how does the contraceptive pill stop pregnancy?

Answer 8

the pill contains oestrogen and progesterone so therefore the levels of oestrogen and progesterone in the body will be high, if they are high it means that the levels of FSH and LH are going to be low and that means the egg won’t mature and won’t release

Question 9

what are 2 types of treatment that can be given to increase the chances of pregnancy?

Answer 9

IVF and ART

Question 10

what does IVF do?

Answer 10

the mother is given FSH and LH to encourage the release and maturing of an egg, they are extracted from the mother and fertilised in a lab using sperm, they develop an embryo and then it is inserted into the uterus

Question 11

what are benefits and problems with IVF?

Answer 11

benefits:
- provides a way for infertile couples to have a child

problems:
- doesn’t always work
- expensive
- side effects to the woman

Question 12

what is homeostasis?

Answer 12

maintain a constant environment in the body

Question 13

what are 3 things homeostasis controls?

Answer 13

• body temperature
• water levels
• blood glucose concentration

Question 14

what is thermoregulation?

Answer 14

keeping the internal body temperature constant (37 degrees celsius), if it increases it causes enzymes to denature

Question 15

what is osmoregulation?

Answer 15

keeping the concentration of blood constant , if the blood becomes too dilute water will move in by osmosis causing it to swell and burst

Question 16

explain 2 things that will happen if the bodys temperature becomes too high

Answer 16

• sweating: water evaporates from the skins surface so it transfers heat energy from the skin to the environment
• vasodilation: blood vessels widen closer to the surface of the skin to increase heat loss

Question 17

explain two things that will happen if the bodys temperature gets too low

Answer 17

• hairs stand on end: to create an insulating layer and trap warm air
• shivering: muscles contract rapidly to generate heat from respiration

Question 18

what happens if the blood glucose levels are too high?

Answer 18

glucose gets converted into glycogen by the hormone insulin

Question 19

what happens if the blood glucose levels are too low?

Answer 19

glycogen gets converted into glucose by the hormone glucagon

Question 20

what is type 1 diabetes?

Answer 20

where the pancreas cannot produce enough insulin, it is genetic, can be cured using insulin injections

Question 21

what is type 2 diabetes?

Answer 21

where the body stops responding to insulin, caused by a poor lifestyle, can be treated with fixing lifestyle or insulin injections

Question 22

how do you calculate BMI?

Answer 22

BMI= mass (kg)/height^2 (m)

Question 23

which route does blood take in order to be purified?

Answer 23

• blood which has impurities travels in the renal artery to the kidney
• the kidney regulates the levels of urea and salt in the blood
• the purified blood returns to the circulation through the renal artery
• the impure blood gets sent to the bladder for excretion

Question 24

what is ADH?

Answer 24

a hormone that prevents you from urinating

Question 25

how is urea produced?

Answer 25

from the break down of excess amino acids in the liver

Question 26

what is dialysis?

Answer 26

artificial method of filtering the blood to remove toxins and excess substances