Nerves and Hormones

Question 1

What does the nervous system enable?

Answer 1

The nervous system enables humans to react to their surroundings and coordinate their behaviour.

Question 2

What is the name for cells that detect stimuli?

Answer 2

Receptors.

Question 3

What is a stimulus?

Answer 3

A change in the environment.

Question 4

What three features do light receptor cells contain?

Answer 4

A nucleus, cytoplasm and a cell membrane.

Question 5

How do receptors get information to the brain?

Answer 5

Using nerve cells/neurons.

Question 6

What happens in a basic reflex arc?

Answer 6

Question 7

What is a synapse and how does it work?

Answer 7

A synapse is a gap between two neurons. When an impulse arrives at the junction between two neurons, chemicals are released which cross the synapse and arrive at the receptor sites on the next neuron. This starts an electrical impulse in the next neuron.

Question 8

What is a hormone?

Answer 8

Hormones are chemical messengers secreted by glands and are usually transported to their target audience by the blood stream.

Question 9

Which out of the below is data about hormones and which is data about nerves?

Answer 9

A=nerves B=hormones

Question 10

What is ovulation and what day of the menstural cycle does it occur at?

Answer 10

Ovulation is the release of a mature egg from the ovary and it occurs at day 14.

Question 11

How long is the menstrual cycle?

Answer 11

28 days long.

Question 12

What is menstruation and how long does it last for?

Answer 12

Menstruation lasts for 5 days and it is the breaking down of the lining of the uterus.

Question 13

FSH is a hormone secreted by the pituitary gland. Give the two roles of FSH.

Answer 13

1. Causes an egg to mature in one of the ovaries
2. Stimulates the production of oestrogen in the ovaries.

Question 14

Oestrogen is a hormone that is secreted by the ovaries. What are its three main roles?

Answer 14

1. Causes the pituitary gland to produce LH
2. Inhibits the release of FSH
3. Builds up the lining of the uterus.

Question 15

LH is a hormone involved in the menstrual cycle that is produced in the pituitary gland. Describe its role.

Answer 15

Stimulates the release of an egg at around the middle of the menstrual cycle from the ovary.

Question 16

What is the contraceptive pill?

Answer 16

This stops somone from becoming pregnant. It may contain oestrogen and progesterone to stop eggs from becoming mature or to stop egg production.

Question 17

What is the difference between early birth control pills and ones used today.

Answer 17

Early birth control pills contained large amounts of oestrogen which caused women to suffer significant side effects however now they contain very low doses of oestrogen and you can even get progesterone only pills.

Question 18

What are fertility treatments? How do they work?

Answer 18

They are ways to help increase fertility. Giving FSH and LH in a fertility drug can stimulate egs to mature and stimulates oestrogen production. They are used to make lots of eggs mature at the same time time. The eggs are then collected and placed in to a petri dish where they are mixed with a sample of semen. The sperm and eggs mix. Once the eggs have been checked to ensure that they are developing correctly they are inplanted in to the uterus.

Question 19

Describe which internal conditions need to be kept constant.

Answer 19

1. The water content of the body – water leaves
   the body via the lungs when we breathe out and via the skin when we sweat to cool us down, and excess water is lost via the kidneys in the urine
2. The ion content of the body – ions are lost via the skin when we sweat and excess ions are lost via the kidneys in the urine
3. Temperature – to maintain the temperature at
   which enzymes work best
4. Blood sugar levels – to provide the cells with
   a constant supply of energy.

Question 20

How do plant shoots respond to light and gravity?

Answer 20

Question 21

How do plant roots respond to gravity and moisture?

Answer 21

Question 22

What is auxin?

Answer 22

Auxin is a plant growth hormone