endocrine

Question 1

what is contraception

Answer 1

Contraception = preventing pregnancy by

Question 2

what is oral contraception

Answer 2

Oral contraception - these pills contain female hormones
the combined oral contraceptive pill contains low doses of oestrogen and progesterone

Question 2

How does the combined oral contraceptive pill prevent pregnancy?

Answer 2

the contraceptive pill prevents pregnancy because ;
it contains oestrogen which inhibits fsh
it contains progesterone which inhibits the use of fsh and lh
fsh causes eggs to mature
lh triggers the release of the egg
if both of these homones are inhibited it wont allow an egg to develop and would prevent a pregnancy

Question 3

Another contraceptive pill stops progesterone from being produced. How does this pill prevent pregnancy?

Answer 3

without a uterus lining there will be no where for the egg to be implanted

Question 4

how can pills that make mucus prevent pregnancy

Answer 4

There are pills that make mucus in the cervix, in order to prevent sperm getting through

Question 5

how does a contraceptive implant work and what does it release

Answer 5

tiny tube inserted under the skin by a doctor –> slowly releases progesterone

Question 6

what are contraceptive injections? how long do they last

Answer 6

progesterone only injections - only last 12 weeks

Question 7

what is a contraceptive patch?

Answer 7

Patch is stuck to the skin and replaced every 7 days - hormones are directly released into the bloodstream

Question 8

what do contraceptive patches release

Answer 8

contains oestrogen and progesterone

Question 9

what are spermicides and are they effective

Answer 9

chemicals that kill or disable sperm - not very effective

Question 10

how do condoms prevent pregnancy?

Answer 10

prevents the egg and sperm from meeting

Question 11

what are 2 advantages of condoms

Answer 11

No side effects, offers protection against some STDs

Question 12

what is a disadvantage of condoms

Answer 12

they can get damaged and sperm can get through

Question 13

what is a cap

Answer 13

thin rubber diaphragm that is placed over the cervix before intercourse to prevent entry of sperm

Question 14

what is advantage of a cap

Answer 14

no side effects

Question 15

what are Intrauterine devices (IUDs)

Answer 15

small structures inserted into the uterus by a doctor

Question 16

how long do IUDs last

Answer 16

these last for 3-5 years - and can be removed any time if you want to become pregnant

Question 17

what is the rhythm method?

Answer 17

abstaining from intercourse around ovulation

Question 18

what is a vasectomy?

Answer 18

sperm ducts are cut and tied to prevent the sperm from getting into the semen

Question 19

what is Tubal sterilisation

Answer 19

Women can get their oviducts (fallopian tubes) cut and tied to prevent an egg reaching the uterus

Question 20

name 3 things that are linked to infertility

Answer 20

a lack of female hormones
damaged oviducts
lack of sperm in the semen

Question 21

what are 3 common causes of infertilty

Answer 21

obesity
eating disorders (anorexia nervosa, bulimia)
age

Question 22

what does IVF stand for

Answer 22

IVF = In Vitro Fertilisation

Question 23

what is in vitro

Answer 23

In Vitro = within cells - so this means you are fertilising on a cellular level - in a lab, in a petri dish

Question 24

under what cirucumstances can IVF be used

Answer 24

1. the oviducts have been damaged/blocked by infection 2. a donor egg has to be used 3. there is no obvious cause for long term infertility 4. if a man produces very little sperm or the sperm has not matured

Question 25

what hormones are given in fertility treatment

Answer 25

A combination of FSH and LH can be used in fertility treatments to cause eggs to mature in the ovary and to trigger ovulation

Question 26

what is the function fsh

Answer 26

matures trhe egg

Question 27

what is the function LH

Answer 27

triggers the release of an egg

Question 28

what is the function of prostrogen?

Answer 28

maintans uterus lining

Question 29

what is fertilisation

Answer 29

when the nuclei of the egg and the sperm fuse

Question 30

what is a fertilised egg called

Answer 30

zygote

Question 31

what is the process of ivf

Answer 31

Doctors give the mother synthetic FSH and LH --> to stimulate maturation of egg and ovulation Collect the egg from the ovary and collect the father’s sperm and fertilise them in the lab - fertilisation =when the nuclei of the egg and the sperm fuse Fertilised eggs (zygotes) kept in special solution in warm conditions to develop into embryos When they are minute balls of cells, one or two are inserted back into the mother’s uterus

Question 32

what are the advantages of ivf

Answer 32

IVF increases the chance of multiple pregnancy the mature eggs produced by a woman using fertility drugs may be collected and stored --> ethical issues

Question 33

what are the disadvantages of ivf

Answer 33

Expensive for society and people --> many will want to pay for repeated treatments Not always successful - especially with age Younger gametes (sex cells - egg cell and sperm cell) can be used BUT they won’t biologically be the parent’s child Has health risks for mother - is emotionally and physically stressful Costs hospital a lot to incubate premature births --> if they survive they are most likely to be severely disabled.

Question 34

what is tropism

Answer 34

Tropism = the movement of the plant in response to a stimulus

Question 35

what is stimulus

Answer 35

Stimulus = a change in the environmen

Question 36

what is Phototropism

Answer 36

Phototropism = plant’s response to light

Question 37

what is Gravitropism/Geotropism

Answer 37

Gravitropism/Geotropism = plant’s response to the force of gravity

Question 38

what happens in photoropism

Answer 38

Auxin moves from the lit side of the shoot to the unlit side Cells on that side become elongated by the auxin, causing the shoot to bend towards the light Once light falls evenly on the shoot, the auxin levels will be equal on both sides, so grows straight again

Question 39

what is gibberellins

Answer 39

Gibberellins = plant hormones

Question 40

what are gibberellins important for

Answer 40

important in initiating seed germination and at the start, giberellins trigger the breakdown of food stores at the start, and stimulate the growth of plant stems

Question 41

what is ethene used for

Answer 41

1. important in controlling cell division 2. important in fruit ripening

Question 42

how does dipping plants in to root powder effect the plant

Answer 42

By dipping or cutting into rooting powder, that contains auxin (IAA), chances of success are higher

Question 43

what are auxins useful for

Answer 43

Auxins make effective weed-killers

Question 44

describe how auxins(weed killers) kill plants

Answer 44

when sprayed, it’s absorbed, sending the plant into rapid uncontrolled growth, which kills it

Question 45

what are selective herbicides?

Answer 45

Selective herbicides = herbicides that affect specific plants

Question 46

what are 3 uses of gibberellins

Answer 46

Brewing industry = speeds up germination of barley seeds which are used to make malt Promotes flowering throughout the year, especially in pot plants Increase the size of fruit