bp2

Question 1

what is the endocrine system?

Answer 1

the endocrine system is composed of glands which secrete chemicals called hormones directly into the bloodstream. the blood carries the hormone to a target organ where it produces an effect.

Question 2

differences between the nervous system and the endocrine?

Answer 2

the nervous system is extremely fast. effects of the nervous system tend to be short lived; the endocrine system is slower delivered but longer lasting effects

Question 3

what is the role of the pituitary gland?

Answer 3

the pituitary gland in the brain is a ‘master gland’ which secretes several hormones into the blood in response to body conditions. these hormones in turn act on other glands to stimulate other hormones to be released to bring about effects.

Question 4

role of the ovaries/testes?

Answer 4

releases hormones involved in puberty/reproduction

Question 5

role of testosterone?

Answer 5

stimulates the testes to produce sperm

Question 6

what is ovulation?

Answer 6

once puberty eggs in the ovaries start to mature, every 28 days an egg is released.

Question 7

describe the process of menstruation

Answer 7

every 28 days, ovulation takes place. in preparation for this, the uterus lining becomes thick and spongy.

the egg makes it’s way down to the uterus. if sperm is present, then the egg can be fertilised. it implant into the uterus wall and develop a baby. if the egg gets fertilised, both the egg and the uterus lining are released.

Question 8

role of follicle stimulating hormone (FSH)?

Answer 8

causes an egg to mature in the ovary

Question 9

role of luteinising hormone (LH)?

Answer 9

causes egg to be released (aka ovulation)

Question 10

role of oestrogen and progesterone?

Answer 10

maintains the uterus lining, incase the egg is fertilised and implants

Question 11

role of the thyroid gland?

Answer 11

produces hormones involved in growth and in regulating the body’s basal metabolic rate.

Question 12

role of the adrenal glands?

Answer 12

released the hormone adrenaline, which is produced in times of fear or stress

Question 13

what is blood glucose concentration monitored by?

Answer 13

the pancreas

Question 14

what hormone is released if blood sugar level is too high?

Answer 14

the pancreas produces the hormone insulin that causes glucose to move from the blood into the cells.

Question 15

where is excess glucose converted to?

Answer 15

in liver and muscle cells

Question 16

what is excess glucose converted to?

Answer 16

converted to glycogen for storage.

Question 17

what is diabetes?

Answer 17

where blood glucose control does not work effectively

Question 18

describe type 1 diabetes

Answer 18

the pancreas does not produce enough insulin.

people monitor their blood glucose concentration and inject themselves with insulin if blood glucose rises too much, eg after a carb rich meal.

Question 19

describe type 2 diabetes

Answer 19

the body cells stop responding to insulin produced by the pancreas.

Question 20

how is type 2 diabetes treated?

Answer 20

diets containing a controlled level of carbohydrates, this is to prevent the blood glucose concentration from rising too high. taking exercise is also advised.

Question 21

risk factors for type 2 diabetes?

Answer 21

obesity

Question 22

what happens if the blood glucose concentration falls?

Answer 22

the pancreas releases the hormone glucagon. glucagon triggers liver cells to convert glycogen stores back to glucose, and this glucose is released into the blood, causing the blood glucose level to return to normal.

Question 23

how could infertility be caused?

Answer 23

men have a reduced sperm count, women find it difficult to conceive.

Question 24

example for treatments for fertility?

Answer 24

a woman is given FSH and LH. this causes the woman to ovulate more than usual, and this increases her chances of becoming pregnant through sexual intercourse. scientists call this a fertility drug.

Question 25

describe the process of IVF

Answer 25

the mother is first treated with FSH and LH. this causes several eggs to mature. these eggs are collected from the mother and sperm from the father is collected. it's used to fertilise eggs in the laboratory. the fertilised eggs then develop into embryos. once the embryos are tiny balls of cells, these are inserted into the mother's uterus and then can develop inside the mother the usual way

Question 26

benefits of IVF?

Answer 26

gives the woman a chance to have a baby of her own.

Question 27

problems with IVF?

Answer 27

low success rates emotionally stressful for both parents physically demanding for the mother leads to multiple births which is risky for both the babies and the mother

Question 28

opinions about IVF?

Answer 28

embryos are destroyed and some people find that unethical. IVF is expensive and some people think that this money could be spent on other medical issues.

Question 29

what happens when thyroxine level falls?

Answer 29

the pituitary gland releases the hormone TSH into the bloodstream. TSH triggers the thyroid gland to release more thyroxine into the blood. the increased level of thyroxine is now detected by the brain and prevents the pituitary gland from releasing TSH. as the TSH level falls, the thyroid gland releases less thyroxine.

Question 30

why are producers important in food chains?

Answer 30

they synthesise complex molecules.

Question 31

what is glucose an example of?

Answer 31

biomass

Question 32

what are predators?

Answer 32

consumers that kill and eat other animals

Question 33

what is a stable community?

Answer 33

a community where all of the biotic and abiotic factors are in balance

Question 34

what is random sampling?

Answer 34

method used to compare the numbers of organisms in different areas

Question 35

what is a quadrat?

Answer 35

wooden or plastic square. can used to record the number of plants or slow-moving animals within it

Question 36

why use sampling along a transect?

Answer 36

to investigate whether the number of species change while moving along a habitat

Question 37

what is a transect?

Answer 37

a line such as a tape measure or a piece of rope

Question 38

what brings carbon into the carbon cycle?

Answer 38

photosynthesis

Question 39

what returns carbon back into the atmosphere?

Answer 39

respiration

Question 40

what can cause dissolved oxygen levels to fall?

Answer 40

fertilisers and untreated sewage. low dissolved oxygen levels can kill aquatic organisms.

Question 41

what can cause acid rain?

Answer 41

burning coal in power stations releases acidic gases

Question 42

why are landfills bad for the environment?

Answer 42

landfills destroy habitats for plants and animals. toxic chemicals can also leach out of landfills and pollute the soil.

Question 43

what is peer review?

Answer 43

checking of scientific papers before being published. peer review helps to detect false claims and make sure that research published in scientific journals is valid.

Question 44

how to maintain biodiversity?

Answer 44

breeding programmes for endangered species preserving and reflooding wetlands

Question 45

how are governments helping to maintain biodiversity?

Answer 45

brazilian governments have established national parks in an attempt to protect the amazon rainforest introducing renewable energy such as windpower which will reduce global warming.

Question 46

how can individuals maintain biodiversity?

Answer 46

recycling waste materials, which reduces landfills.

Question 47

what is biodiversity?

Answer 47

the variety of life in the world or in a particular habitat or ecosystem.

Question 48

why is biodiversity important?

Answer 48

biodiversity provides direct and indirect economic benefits and maintains a healthy biosphere.

Question 49

why is high biodiversity important?

Answer 49

ensures ecosystems are stable as different species depend on each other for things like shelter and food. different species can help maintain the right physical environment for each other

Question 50

human's effect on biodiversity

Answer 50

large areas of forests being destroyed to provide land the land is often used to provide space for grazing cattle or for rice fields, which can be used as biofuels.

Question 51

what are field margins?

Answer 51

areas of land around the edges of fields where wildflowers and grasses are left to grow used to increase biodiversity where one crop is usually grown.

Question 52

what are hedgerows?

Answer 52

dirt walls, several feet thick and covered with shrubbery. used to increase biodiversity where one crop is usually grown.