Chapter B11- Hormonal Coordination Flashcards Preview

GCSE Biology > Chapter B11- Hormonal Coordination > Flashcards

Flashcards in Chapter B11- Hormonal Coordination Deck (12):
1

What are hormones?

What are hormones made by?

What do hormones go through and so to do what?

What does the pituitary gland release and what does this do?

What hormone do the ovaries release?

What two things does this hormone do?

What other hormone does the pituitary gland release?

What does this hormone do?

What is this process called?

Chemical messengers

Specialised tissues called glands

The bloodstream to exert an effect on a target organ

Releases Follicle Stimulating Hormone (FSH) causing an egg to mature

Oestrogen

Inhibits the production of FSH and thickens the uterus lining

Luteinising Hormone (LH) causing the egg to be released

Ovulation.

2

How long does the menstrual cycle last for?

At what day of the cycle does ovulation occur?

What days does the period of the menstrual cycle last for?

What hormone is made to inhibit LH and to maintain the lining of the uterus?

What three things do the follicle cells do in an egg cell?

What is an egg cell called?

What can males or females have if they are infertile as a method for producing a baby?

What does this stand for?

28 days

Day 14

From day 1-7

Progesterone

Help feed the egg, protect it and help it develop

Follicle (follicular cells + Egg cell= Follicle)

They can have IVF

In-vitro fertilisation.

3

What happens in the first stage of IVF?

What happens in the second and third stage of IVF?

What is testosterone and where is it produced?

What does testosterone do?

What two hormones are involved in maintaining the uterus lining?

What does IVF involve and why?

What are three problems of fertility treatment on women?

What is the pill (or the contraceptive pill) an example of and what do these type of contraceptives use and do?

What does the mixed pill contain?

What do these hormones inhibit?

The mature egg and concentrated sperm are left in a petri dish to allow the fertilised egg cell to develop

The embryo is inserted into the lining of the womb and the baby is then born

The main male reproductive hormone produced by the testes

It stimulates sperm production

Oestrogen and progesterone

Giving a mother FSH and LH to stimulate the maturation of several eggs

-It is very emotionally and physically stressful
-The success rates are not high
-It can lead to multiple births which are a risk to both the babies and the mother

Oral contraceptives which use female hormones to prevent pregnancy

Low doses of oestrogen along with some progesterone

The production and release of FSH affecting the ovaries so no eggs mature.

4

What else do the hormones in the contraceptive pill do and what does this prevent?

What else do the hormones do and what does this also prevent?

What are three side effects of using the contraceptive pill?

What are spermicides?

What is an advantage and disadvantage of using spermicides?

What do barrier methods of contraception do?

What do condoms offer?

What is a disadvantage of condoms?

What do barrier methods work better combined with?

Prevent the uterus lining developing, preventing implantation

Make the mucus in the cervix thicker to prevent sperm from getting through

Raised blood pressure, thrombosis and breast cancer

Chemicals that kill or disable sperm

They are readily available but aren't very effective at preventing pregnancy

Prevent the sperm from reaching the egg

Some protection against sexually transmitted diseases

They can get damaged and let sperm through

Spermicide.

5

What is abstinence?

What does this do and what is it also referred to as?

What is an advantage and disadvantage of using this?

What does abstinence work better combined with?

What can couples also do if they don't want any more children?

How does this happen in men and what does this do?

What is this process called?

How does this happen in women and what does this do?

What is one disadvantage of this method?

What are advantages of these methods?

Abstaining from intercourse around ovulation or when an egg is in the oviduct

Means sperm can't fertilise the egg (also known as the rhyme method)

It has no side effects but is very unreliable

Ovulation indicators

They can be surgically sterilised

The sperm ducts are cut and tied, preventing sperm from getting into the semen

Vasectomy

The oviducts are cut or tied to prevent the egg reaching the uterus and the sperm reaching the egg

Women will need a general anaesthetic for the surgery

They give effective, permanent contraception with no risk of human error.

6

What are/what do plant hormones do?

How are these hormones transported?

What is/does auxin do?

What two processes does this hormone control and what is their names?

Where is auxin produced?

Where does this hormone move to and why?

What happens if the tip of a shoot is removed and what could it then lead to?

What does extra auxin promote but also inhibit?

What happens when a shoot tip is exposed to light?

What does this do to the cells in the shoot?

Chemicals that make a large change on organs or tissues

Through the phloem

A plant hormone that controls growth near the tips of shoots and roots

It controls the growth of a plant in response to light (phototropism) and gravity (gravitropism or geotropism)

Produced in the tips

Moves backwards to stimulate the cell elongation (enlargement) process which occurs in cells just behind the tips

No auxin is available and the shoot may stop growing

Promotes growth in the shoot but inhibits growth in the root

More auxin accumulates on the side that's in the shade than the side that's in the light

This makes the cells grow (elongate) faster on the shaded side so the shoot bends towards the light.

7

Where do shoots grow away from?

Where do roots grow towards?

What happens when a shoot is growing sideways and what happens to the distribution of auxin?

What two things does this cause as a result?

What will a root growing sideways also have?

What does the extra auxin do in a root?

What do this mean happens to the cells on top?

What do this mean also happens to the root?

Shoots grow away from gravity

Roots grow towards gravity

Gravity produces an unequal distribution of auxin in the tip, with more auxin on its lower side

This causes the lower side to grow faster, bending the shoot upwards

More auxin on its lower side

In a root the extra auxin inhibits growth

The cells on the top elongate faster

The root bends downwards.

8

In what two ways can plant hormones be made?

What are auxins useful for?

What are most weeds growing in fields or crops or in a lawn compared to grass?

What has been developed to combat this and how?

How do they achieve this, in detail?

What is a cutting?

What usually happens if you put these in soil?

What happens if you add rooting powder and what does it contain?

What does this enable growers to produce?

How can plant cells in tissue culture (in detail)?

They can be extracted or artificial copies can be made

Controlling plant growth

Broad leaved compared to grasses and cereals which have very narrow leaves

Selective weed killers, developed using auxins, which only affect the broad leaved plants

They totally disrupt their normal growth patterns, which soon kills them, whilst leaving the grass and crops untouched

A part of a plant that has been cut off it, like a branch

They won't grow

They will produce roots rapidly and start growing as new plants as it contains auxins

Lots of clones (exact copies) of a really good plant very quickly

By adding hormones such as auxins to the growth medium (along with nutrients) to stimulate the cells to divide to form both roots and shoots.

9

What does gibberellin stimulate?

What three process does the plant growth hormone stimulate?

What is dormancy?

How does gibberellin help these following control methods, in detail:

Controlling dormancy

Inducing flowering

Growing larger fruits

What does ethene stimulate in plants?

What is ethene and what is it produced by?

What does ethene influence and stimulate in a plant and how does it do these processes?

Stimulates plant stems to grow

Stimulates seed germination, stem growth and flowering

When lots of seeds won't germinate until they've been through certain conditions (for instance a period of cold or dryness)

Seeds can be treated with gibberellin to alter dormancy and make them germinate at times of a year that they wouldn't normally. It also helps make sure all seeds in a batch germinate at the same time

If certain plants are treated with gibberellin, they will flower without any change in their environment. Gibberellin can also be used to grow bigger flowers

If gibberellin is added to certain fruits they will grow larger to match the normal types

Ethene stimulate the ripening of fruit

A gas produced by aging parts of a plant

Ethene influences the growth of a plant by controlling cell division. It also stimulates the enzymes that cause fruit to ripen.

10

What can ethene commercially be used to speed up in plants?

In what two ways can this be used?

What does this mean happens to the fruit?

How/when can ripening of the fruit also be delayed and in what two ways?

How else can chemicals be added and why?

What is adrenaline and where is it released?

When is adrenaline released and how does the brain do this?

How do these glands respond by?

What processes does adrenaline get the body ready for?

What mechanisms does adrenaline trigger to do this and give an example?

What is thyroxine and where is it released?

What does thyroxine play an important role in what process and describe it?

Speed up the ripening of fruits

Either while they are still on the plant or during transportation to the shops

It can be picked while it's still unripe

While the fruit is in storage by adding chemical's that block ethane's effect on the fruit or reduce the amount of ethene that the fruit can produce

Alternatively some chemicals can be used that react with ethene to remove it from the air

A hormone released by the adrenal glands, which are just above the kidneys

Released in response to stressful or scary situations- the brain detects fear or stress and sends nervous impulses to adrenal glands

Respond by secreting adrenaline

It gets the body ready for fight or flight

Triggers mechanisms that increase the supply of oxygen and glucose to cells in the brain and muscles, for instance increases heart rate

Thyroxine is a hormone released by the thyroid gland, which is in the neck

In regulating the basal metabolic rate- the speed at which chemicals reactions in the body occur while the body is at rest.

11

What is your basal metabolic rate?

What is thyroxine also important for and give an example?

When is thyroxine released and why?

What keeps the amount of thyroxine in the blood at the right level?

How does it achieve this, in detail?

What does these processes reduce and so what is the result?

What can hormones be affected by?

What can the body use to control the levels of hormones and other substances in the blood?

What does the body do when it detects that the level of a substance has gone above or below the normal level?

The speed at which chemical reactions in the body occur while the body is at rest

Also important for loads of processes in the body, such as stimulating protein synthesis for growth and development

In response to thyroid stimulating hormone (TSH) which is released from the pituitary gland

A negative feedback system

When the level of thyroxine in the blood is higher than normal, the secretion of TSH from the pituitary glands inhibited stopped

Reduces the amount of thyroxine released from the thyroid gland, so the level in the blood falls back towards the normal

Negative feedback

By using negative feedback systems

It triggers a response to bring the level back to normal again.

12

What happens once the danger is over to adrenaline concentrations?

What does adrenaline not involve?

The adrenal glands stop releasing adrenaline and the systems return to their resulting levels

A negative feedback loop.