The Endocrine System

Question 1

How can information be sent around the body apart from along nerves?

Answer 1

By using hormones.

Question 2

What are hormones?

Answer 2

Chemical molecules released directly into the blood.

Question 3

Where are hormones carried and where to? What do they affect?

Answer 3

In the blood to other parts of the body, but only affect particular cells in particular organs (called target organs).

Question 4

What do hormones control?

Answer 4

Things in organs and cells that need constant adjustment.

Question 5

Where are hormones produced?

Answer 5

In (and secreted by) various glands, called endocrine glands. These glands make up your endocrine system.

Question 6

What length of time of effects do hormones usually have?

Answer 6

Relatively long-lasting effects.

Question 7

Give some examples of glands that produce hormones.

Answer 7

The Pituitary gland - produces many hormones that regulate body conditions. Sometimes called the “master gland” because these hormones act on other glands, directing them to release hormones that bring about a change.
Thyroid - produces thyroxine, which is involved in regulating things like the rate of metabolism, heart rate and temperature.
Adrenal gland - produces adrenaline, which is used to prepare the body for a “fight or flight” response.
The pancreas - produces insulin, which is used to regulate the blood glucose level.
Ovaries (females only) - produce oestrogen, which is involved in the menstrual cycle.
Testes (males only) - produce testosterone, which controls puberty and sperm production in males.

Question 8

What’s the difference between hormones and nerves?

Answer 8

Nerves: Hormones:

• Very fast action - Slower action
• Act for a very short time - Act for a long time
• Act on a very precise area - Act in a more general way