Endocrine System Anatomy

Question 1

What are exocrine glands?

Answer 1

Secrete into a duct that carries secretion to surfaces of body cavities

Question 2

Exocrine gland example

Answer 2

Sweat glands
Mucous glands
Salivary glands
Glands of alimentary canal

Question 3

What are endocrine glands?

Answer 3

Secrete Hormones into extracellular fluid around cells making up the gland
Secretion passes to capillaries & is transported by blood to target cells
“Ductless glands”

Question 4

Purely endocrine glands

Answer 4

Pituitary gland
Pineal gland
Thyroid gland 
Parathyroid gland
Adrenal glands - cortex & medulla

Question 5

Endocrine cells in other organs

Answer 5

Pancreas
Gonads
Thymus
Hypothalamus

Question 6

Hypothalamus

Answer 6

Located at base of brain
Regulates body temp, water balance, heart rate
Functions carried out through pituitary gland

Question 7

Pituitary Gland

Answer 7

Located under hypothalamus
Joined to hypothalamus by stalk - infundibulum
Consists of anterior & posterior lobe

Question 8

Anterior Pituitary Lobe

Answer 8

No nerves connecting it to hypothalamus

Connected by blood vessels

Question 9

Posterior Pituitary Lobe

Answer 9

Doesn’t secrete Substances - not a true gland

Joined by nerve fibres from nerve cell bodies in hypothalamus, pass through infundibulum to posterior lobe

Question 10

Pineal Gland

Answer 10

Decreases in size as you grow older
Role is a mystery
Secreted melatonin - involved in sleep patterns
Stimulated by darkness, inhibited by light

Question 11

Thyroid Gland

Answer 11

Located in neck
Secretes thyroxine - made from iodine & an amino acid
Controls body metabolism by regulating anabolic & catabolic reactions in the body
In turn maintains body and increases oxygen production

Question 12

Parathyroid Glands

Answer 12

4 glands on back of thyroid gland
Produces parathyroid hormone (PTH)
Controls calcium & phosphate levels in blood

Question 13

Thymus

Answer 13

Located in chest above heart, behind breast bone
Shrinks after puberty
Secretes thymosins - influence maturation of T-lymphocytes (disease fighting cells)

Question 14

Adrenal Medulla

Answer 14

Inner part of adrenal glands

Adrenaline - helps prepare body for threatening situations of flight/fight response

Noradrenaline - similar effects adrenaline increases rate & force of heart rate

Question 15

Adrenal Cortex

Answer 15

More than 20 different hormones produced, known collectively as corticosteroids

Aldosterone - acts on kidneys to reduce amount of sodium & increase amount of potassium in urine

Cortisol - with related Hormones, promote normal metabolism, helping body withstand stress & repair damaged tissue

Question 16

Pancreas

Answer 16

Both an exocrine & endocrine gland
Islets of Langerhans - clusters of special cells that are the endocrine part

Insulin - reduces blood sugar levels by promoting uptake of glucose from blood by cells of body,

Question 17

Gonads

Answer 17

Androgens - produced by testes, responsible for development & maintenance of male sex characteristics

Oestrogen/progesterone - produced by ovaries, stimulate development & maintenance of female sex characteristics

With pituitary gland regulate menstrual cycle & changes during pregnancy

Question 18

Other Endocrine Tissue

Answer 18

Stomach/small intestine - coordinate exocrine glands of digestive system

Heart - helps reduce blood pressure

Placenta - helps maintain pregnancy, development of foetus

Kidneys - erythropoietin (EPO) , stimulate production of rbc by bone marrow