Endocrine System

Question 1

The Endocrine System

Answer 1

Endocrine glands are located all around the body and are responsible for secreting hormones.
Once secreted the hormones then travel to their target organ in which they can have a positive (stimulating) or negative (preventative) effect.

Question 2

Hormones are split into 4 categories.

Answer 2

Metabolic- controlling the rate and balance of chemical reactions.
Kinetic- Allowing movement of substances around the body.
Behavioural- Controlling behaviour
Morphogenetic- Changing the appearance and structure of tissues.

Question 3

Endocrine Glands

Answer 3

Pituitary gland (Anterior and Posterior)
Thyroid gland 
Parathyroid gland 
Pancreas
Testes
Ovaries 
Adrenal glands

Question 4

Pituitary gland

Answer 4

Located near the centre and bottom of the brain.
It produces a number of critical hormones that control many parts of the body.
Also known as the master gland.

Question 5

Anterior Pituitary

Answer 5

Follicle Stimulating Hormone(FSH)- Stimulates ovarian follicles.
Adrenocorticotrophic Hormone (ACTH)- release of adrenocortical hormones.
Somatotrophin- Controls epiphyseal growth.
Thyrotrophic Stimulating Hormone (TSH)- Release of thyroid hormone.
Luteininsing Hormone (LH)- Brings about ovulation.
Interstital Cell Stimulating Hormone- Stimulating the secretion of testosterone.
Prolactin- Stimulates mammary glands and milk production.

Question 6

Posterior pituitary

Answer 6

Anti-diuretic Hormone (ADH)- Targets nephrons to increase the reabsorption of water.
Oxytocin- Stimulates uterine contractions and produces milk ‘let down’.

Question 7

Thyroid Gland

Answer 7

Two lobed gland in the neck.
It is responsible for the production of:
- Thyroxin- Control metabolic rate.
- Tri-iodothyronine- Control of metabolic rate.
- Thyrocalcitonin- If there is high level of calcium, this hormone is produced to reduce calcium uptake from the bones.

Question 8

Parathyroid Gland

Answer 8

Four small glands located adjacent or within the thyroid gland.
They are responsible for the secretion of:
- Parathormone (PTH)- stimulates calcium reabsorption from bones and promotes calcium uptake.

Question 9

Adrenal Glands

Answer 9

Two adrenal glands are located on the top of each kidney.
They essentially contain two separate endocrine organs.
The outer portion or core of the adrenal gland is called the adrenal cortex.
The inner portion of the gland is called the adrenal medulla.
Responsible for Secreting:
- Glucocorticoids- Raises blood glucose and reduces inflammatory responses.
- Aldosterone- Regulates sodium uptake.
- Adrenaline and Noradrenaline- Fear, Fight or Flight response.

Question 10

Pancreas

Answer 10

Is an oblong, flattened gland located in the abdomen, adjacent to the stomach and small intestine.
It has both an endocrine and exocrine function.
Responsible for the production of:
- Insulin- Increases uptake of glucose into cells.
- Glucagon- Breaks down glycogen.
- Somatostatin- Prevents swings in glucose levels.

Question 11

Ovaries

Answer 11

The female reproductive gland.
Produces:
- Oestrogen- Signs of oestrus (menstrual cycle)
- Progesterone- Maintains pregnancy, prepares reproductive tract and develops mammary glands.

Question 12

Testes

Answer 12

Un-neutered male dogs and cats have twin reproductive glands, called testes.
Produce:
-Testosterone- Required for spermatogenesis and male characteristics.