10.1 Hormones: Chemical Regulators

Question 1

What is the endocrine system?

Answer 1

The endocrine system is a system of small
organs that involve the release of extracellular signalling molecules known as hormones.

Question 2

What are Hormones?

Answer 2

Hormones are chemical regulators
produced by cells in one part of the body
that affect cells in another part of the
body.

Question 3

Chemicals produced in glands and secreted
directly into the bloodstream are referred
to as

Answer 3

ENDOCRINE HORMONES

Question 4

NON-TARGET HORMONES

Answer 4

Stimulate various parts of the body

Question 5

TARGET HORMONES

Answer 5

Stimulate specific
sites of the body

Question 6

NON-TARGET Examples

Answer 6

• Growth Hormone stimulates the
  development of long bones
• Insulin regulates blood sugar by increasing
  permeability to glucose
• Epinephrine (A.K.A Adrenaline) is produced
  in times of stress

Question 7

TARGET Examples

Answer 7

• Parathyroid hormone regulates calcium
  levels in the body
• Gastrin stimulates cells of the stomach to
  produce digestive enzymes

Question 8

Chemical Control Systems

Answer 8

The nervous system enables the body to
quickly adjust to environmental changes.

The endocrine system is designed to
maintain the body over longer periods of
time.
- For example growth hormone and various
sex hormones regulate and sustain the
body for many years.

Question 9

Chemical Signals: Steroid and Protein
Hormones

Answer 9

Hormones can affect cells when they combine with
cell receptors.

Not all cells have the receptors for all hormones and
some cells have more receptors than

Question 9

Steroid Hormones

Answer 9

1. Diffuses through the cell membrane
2. Attaches to a target receptor molecule
3. The hormone-receptor complex moves
   into nucleus and attaches to DNA
4. This activates a gene that sends a
   message to the ribosomes in the
   cytoplasm to create specific proteins.

Question 10

Steroid Hormones =

Answer 10

Made from cholesterol (Lipidcompound) and includes male and female sex hormones and cortisol (stimulates the conversion
of amino acids to glucose by the liver)
- FAT SOLUBLE

Question 10

Protein Hormone

Answer 10

1. Hormone released from cell
2. Hormone attaches to receptor site on cell
   (Doesn’t diffuse across the membrane)
3. Hormone-receptor turns ATP into cyclic
   AMP (Adenosine monophosphate)
4. Cyclic AMP acts as a messenger which
   activates enzymes/directs protein
   synthesis

Question 11

Protein Hormones =

Answer 11

Obviously made from
proteins (Chains of amino acids). Includes insulin
and growth hormone.
- WATER SOLUBLE

Question 12

Pituitary Gland

Answer 12

The pituitary gland exercises control over other endocrine glands and so may be considered the queen of the GLANDS!

The pituitary is connected to the hypothalamus.
The hypothalamus sends nerve signals to the
pituitary which stores and releases hormones.

Question 13

The pituitary gland is made up of two lobes:

Answer 13

Posterior Lobe & Anterior Lobe

Question 14

Posterior Lobe

Answer 14

This lobe is responsible for:
- Storing and releasing hormones produced by
the hypothalamus such as ADH and OXYTOCIN

Question 15

Anterior Lobe

Answer 15

This lobe is responsible for:
- Producing hormones and releasing them
when stimulated by the hypothalamus