Endocrine System

1
Endocrine System

• Year 9 Science

2
Endocrine system

• It releases hormones into the blood to signal
  other cells to behave in certain ways.
• They are chemicals that are released slowly from
  different glands throughout the body.

3
Interaction of Glands

• The hypothalamus is located in the brain and
  controls the release of hormones from the
  pituitary gland.
• It is an important link between the endocrine and
  nervous systems.

4
Hormones

• Hormones are chemical substances that usually act
  as messengers in the body.
• Hormones are made by endocrine glands and
  released into the bloodstream or the fluid
  surrounding cells and send signals to target
  organs.

• They are slower to act than the nervous system

5
Pituitary Gland

• Located at the base of the brain It secretes nine
  hormones that regulate many body functions and
  controls functions of other glands.
• It's often called the "master gland.

6
Thyroid

• The thyroid is located in the neck, just below
  the Adams apple
• It is controlled by hormones from the pituitary.
• It produces the hormone thyroxin which is
  involved in controlling metabolism, heart rate,
  heat regulation, and brain development.

7
The Adrenal Glands

• The body also has two triangular adrenal glands,
  one on top of each kidney.
• It controls the rate at which your heart beats
  and your breathing due.
• It secretes the hormone adrenaline which
  increases your heartbeat and breathing when your
  frightened or nervous.
• It provides a
• fight or flight response

8
Pancreas

• The pancreas produces two important hormones,
  insulin and glucagon.
• These hormones together maintain a steady level
  of glucose, or sugar, in the blood.

9
Female Gonads Ovaries

• Produce ova (eggs) and secrete the female
  hormones estrogen progesterone.
• Estrogen is involved in beginning puberty
• Estrogen and progesterone are also involved in
  the regulation of a girl's menstrual cycle. These
  hormones also play a role in pregnancy.

10
Males Gonads - Testes

• The male gonads, or testes are located in the
  scrotum.
• They secrete hormones called androgens, the most
  important of which is testosterone.