topic 5,6

Question 1

what is homeostasis

Answer 1

maintaining a stable internal environment

Question 2

negative feedback

Answer 2

when the body senses something is too low or too high so to counteract does the opposite to reach a desired level

Question 3

order which the nervous system kicks in

Answer 3

stimulus
receptor
sensory neurone 
cns
motor neutron 
effector 
response

Question 4

synapses

Answer 4

gaps between the nerves

the nerve signal is transferred by chemicals

Question 5

reflex

Answer 5

stimulus 
sensory neurone 
relay neurone 
motor neurone 
effector

Question 6

glands

Answer 6

pituitary gland - produces many hormones, called the master gland

thyroid - produces thyroxine to regulate rate of metabolism, heart rate and temp.

adrenaline gland - produces adrenaline for fight or flight

the pancreases - produces insulin to regulate blood glucose levels

Question 7

controlling blood glucose

Answer 7

the pancreas’s detects a rise in glucose, so responds by secreting insulin into the bloodstream. insulin causes cells to take up more glucose from the blood and to store it as glycogen.

when levels are too low, glucagon is released into the blood. this does the opposite of insulin and causes glycogen to form into glucose.

Question 8

hormones

Answer 8

hormones are chemical messenger which travel in the blood to activate target cells

Question 9

type 1 diabetes

Answer 9

a condition where the pancreas doesn’t produce or doesn’t produce enough insulin

Question 10

type 2 diabetes

Answer 10

when a dude becomes resistant to their own insulin

Question 11

kidneys

Answer 11

kidneys filter the blood and substances removed are urea and urine

Question 12

adh

Answer 12

the brain monitors the water levels within bloodstream. when it’s too low the pituitary gland releases adh so the kidney tubules become more permeable and more water is reabsorbed.

Question 13

stages of menstrual cycle

Answer 13

stage 1 - uterus lining break down for 4 days

stage 2 - lining of uterus builds up again from day 4 to 14

stage 3 - egg is released from ovary at day 14

stage 4 - the wall is maintained for about 14 days until day 28

Question 14

hormonal interaction in the menstrual cycle

Answer 14

FSH is produced in the pituitary gland and causes the egg to mature and stimulates ovaries to produce oestrogen

oestrogen stimulates growth of uterus and stimulates release of LH. stops FSH

LH made in pituitary, stimulates release of egg

progesterone produced by the ovaries to maintain the lining.

Question 15

contraceptives

Answer 15

skin patches
implants 
the pill
barrier methods - condoms 
intrauterine devices ( T-shaped device)
surgical methods 
natural methods

Question 16

ivf

Answer 16

maturation of multiple eggs stimulates

eggs collected then from the ovaries

fertilised

eggs grow into embryos

one or two transferred into the woman’s uterus.

Question 17

auxin

Answer 17

a plant hormone at the tip of a root or shoot. responsible for phototropism and gravitropism. also used to kill weeds and help grow cuttings

Question 18

giberellins

Answer 18

controlling dormancy
inducing flowering
growing larger fruit

Question 19

ethene

Answer 19

speed up ripening

Question 20

gametes

Answer 20

sperm and egg

gametes ate made through meiosis

Question 21

meiosis

Answer 21

chromosomes line up in pairs

cells pulled apart so that two cells have one copy of each chromosome

pulled apart again to them produce 4 gametes

Question 22

mendel

Answer 22

monk who liked gardening. experimented with peas. crossed short pease with tall ones. all 4 offspring were tall.

crossed two tall peas. made 3 tall and 1 short

Question 23

genetic engineering

Answer 23

to transfer a gene for a characteristic from one organism into another organism so that it has the characteristic

Question 24

interdependence

Answer 24

all species rely on each other. if one goes this effects the entire ecosystem

Question 25

habitat

Answer 25

place where organisms live

Question 26

population

Answer 26

all organisms of one species living in a habitat

Question 27

community

Answer 27

the populations of all species living within a habitat

Question 28

abiotic factors

Answer 28

non-living factors of the environment - temp.

Question 29

biotic factors

Answer 29

living factors if the environment - food

Question 30

ecosystem

Answer 30

the interaction of a community of living organism with non-living parts of their environment

Question 31

small to big

Answer 31

dna
gene
chromosome
nucleus

Question 32

genome

Answer 32

the entire set of genetic material in an organism

Question 33

nucleotides

Answer 33

dna are made up by repeating polymers called nucleotides. they made up of bases, sugars and phosphates.

bases : A and T - C and G

Question 34

theory of evolution

Answer 34

All of todays species have evolved from simple life forms that first started to develop over three billion years ago

idea presented by charles darwin

Question 35

antibiotic resistance

Answer 35

bacteria have random mutations which sometimes lead to them being more resistant to an antibiotic. because they reproduce rapidly they can also evolve quickly

Question 36

water cycle

Answer 36

water evaporates from land and sea. turns into clouds and then is rained down

Question 37

carbon cycle

Answer 37

plants gain carbon from air. then ate eaten. animals die. carbon then goes into the ground. plants then absorb from the grounds and then die to decay and be turned into fossil fuels

Question 38

global warming

Answer 38

increasing levels of co2 and methane
increasing greenhouse effect
global warming
other types of climate changes