B5: The Endocrine System Flashcards
What is the endocrine system?
All the glands that produce hormones.
What are hormones?
Chemical molecules released directly into the blood. They’re carried in the blood to other parts of the body, but only affect cells in particular organs (called target organs). They control things in organs and cells that need constant adjustment. They tend to last a relatively long time.
How are nerves different from hormones?
Hormones are slow acting over a large area. They act for a long time.
Nerves are fast acting over a small area. They act for a very short time.
What does the pituitary gland do and where is it located?
Produces LH which stimulates ovulation in females and testosterone production in males.
Produces FSH which stimulates egg development and oestrogen secretion in females, and sperm production in males.
Produces Anti-Diuretic Hormone (ADH) which controls the water content of the blood.
Sometimes called the ‘master gland’ as these hormones act in other glands, directing them to release hormones that bring about change.
It is located at the bottom of the brain.
Explain what the ovaries do.
Produce oestrogen, which is involved in the menstrual cycle.
What do the testes do?
Produce testosterone, which controls puberty and sperm production in males.
What does the thyroid do?
Produces thyroxine, which is involved in regulating rate of metabolism (how fast chemical reactions take place in cells).
What does the adrenal gland do?
Produces adrenaline, which is used to prepare the body for a ‘fight or flight’ response by increasing the glucose and oxygen cells in the brain and muscles.
Explain what the pancreas does.
Produces insulin which lowers blood glucose levels.
Produces glucagon which raises blood glucose levels.
What also makes hormones?
The hypothalamus.
