B3.2 - The Endocrine System

Question 1

Ovulation

Answer 1

Release of a mature egg from an ovary

Question 2

Oestrogen

Answer 2

Hormone causing the uterus lining to thicken/build up

INHIBITS the of production of FSH to stop more than one egg maturing

STIMULATES TO PITUITARY GLAND TO RELEASE LH

Question 3

Luteinising hormone (LH)

Answer 3

Hormone that TRIGGERS ovulation when the amount of hormone is at its PEAK

Question 4

Progesterone

Answer 4

Hormone that maintains the uterus DURING a pregnancy (so high levels during pregnancy)

INHIBITS THE PRODUCTION OF LH

Question 5

Follicle stimulating hormone (FSH)

Answer 5

Hormone secreted by the pituitary gland travels through blood to ovaries, CAUSES EGG TO MATURE

STIMULATES TO PRODUCE OESTROGEN

Question 6

Mnemonic for order of hormones in menstrual cycles

Answer 6

Fear - FSH
Of - Oestrogen
Losing - LH
Pasta - Progesterone

(Or order is H, ‘one’, H, ‘one’)

Question 7

Phototropism

Answer 7

Growing in direction of light (‘photo’)

Aka: Negative Gravitropism

Question 8

Gravitropism

Answer 8

Growing in the direction of gravity

Also known as: Negative Phototropism

Question 9

Auxin

Answer 9

Plant hormone which promotes growth in direction of light stimulus

Question 10

Where is auxin mad in the plant

Answer 10

Near the tip

Or in the roots or shoots

Question 11

What does auxin do the growth of the ROOTS

Answer 11

INHIBITS ROOT GROWTH

but causes more shoot growth

OPPOSITE OF ONE ANOTHER

Question 12

Which side does auxin move to when light exposed

Answer 12

To the shadier/darker side. This causes growth only one one side of the plant, meaning it leans towards to the sun causing positive phototropism

Question 13

What happens if light is evenly distributed on plant

Answer 13

Auxin is evenly distributed and therefore all cells grow at the same rate and the plant grows straight up

Question 14

How does auxin work in the roots

Answer 14

Auxin still gathers to the shadier side, but this inhibits the growth of the shadier side. Therefore, the other side grows more, and causes the roots to follow positive gravitropism, and go downwards

Question 15

Ethene

Answer 15

Plant hormone used to ripen fruits

Question 16

How does ethene ripen fruits

Answer 16

Stimulates the conversion of STARCH TO SUGAR

Question 17

Commercial use of auxin

Answer 17

Weed killers
Rooting powders
Delay ripening
Produce seedless fruits

Question 18

How does auxin kill weeds

Answer 18

Auxin causes it to grow too fast. The rapid uncontrolled movement causes it to die

Question 19

How does auxin promote root growth

Answer 19

Gardeners cut of shoot tips. Dip it in rooting powder (with contains auxin). Auxin promotes growth in the shoots, producing a clone of the original plant

Question 20

Why is auxin used to delay ripening in fruits

Answer 20

Allows a harvest to be collected at the same time and prevents the fruit from dropping off trees to early

Question 21

How does auxin produce seedless fruit

Answer 21

Seeds are made when an insect pollinates plant. Therefore, if you add auxin to the UNPOLLINATED plant, you get seedless fruit

Question 22

Commercial use for ethene

Answer 22

Ripening fruit

Question 23

Why is ethene used to ripen fruits

Answer 23

To allow the fruits to be ready earlier in the growing season

Question 24

Commercial use for gibberellin

Answer 24

Controlling dorancy

Question 25

Gibberellin

Answer 25

Plant hormone which promotes growth in other plants. Especially stem elongation. Ends seed dormancy to allow shoots and flowers to open quicker

Question 26

How does gibberellin control dormancy

Answer 26

Promotes growth and causes shoots/flowers to open earlier.

Question 27

What are hormones

Answer 27

Chemical messengers

Question 28

What makes hormones

Answer 28

Endocrine Glands

Question 29

Target organ

Answer 29

Organ that a hormone has effect on

Question 30

Way to remember sentence for hormone

Answer 30

HAS - hormone name BRITAIN - travels through the blood GOT - by what gland? TALENT - to which target organ

Question 31

Homeostasis

Answer 31

Maintenance of a constant internal environment

Question 32

Names of Endocrine glands

Answer 32

``` Hypothalamus (in the brain) Pituitary gland (in the brain) ``` ``` Thyroid gland (bottom of throat) Adrenal glands (in kidney) Pancreas Ovaries in females Testes in males ```

Question 33

Do hormones travel across the entire body?

Answer 33

YES the hormone travels all around the body (not specific) it is just that ONLY THE TARGET CELLS/ORGAN responds to the hormone

Question 34

How do target cells respond to hormone

Answer 34

The hormone diffuses out of the blood and binds on to the receptors in the cytoplasm/membrane of the target cell. This is stimulated to give a response

Question 35

Endocrine system

Answer 35

All endocrine glands and the hormones they produce

Question 36

Negative feedback

Answer 36

A system in the body which detects a change in a condition and then acts to return the conditions to the normal/desired level.

Question 37

How are thyroxine levels controlled (example of negative feedback)

Answer 37

Hypothalamus detects that cells need more energy Pituitary gland release TSH (thyroid stimulating hormone) Thyroid gland secretes thyroxine Once the hypothalamus detects enough cell energy Pituitary gland stops making TSH Thyroid stops making thyroxine Normal levels return

Question 38

What does adrenaline do?

Answer 38

Prepares the body for intensive action

Question 39

How does the body respond when adrenaline is secreted in the blood?

Answer 39

More respiration to increase ATP production Higher breathing rate to cope with extra demand for oxygen Higher heart rate Diverting blood away from areas such the digestive system towards the muscles