Hormones

Question 1

What peptides and proteins does the Posterior pituitary secrete

Answer 1

Oxytocin (OT)
Antidiuretic hormone (ADH)

Question 2

What peptides and proteins does the anterior pituitary secrete

Answer 2

Human growth hormone (hGH) - 
Thyroid stimulating hormone (TSH)
Follicle-stimulating hormone (FSH)
Luteinising hormone (LH)
Prolactin (PRL)
Adrenocorticotropic hormone (ACTH)
Melanocyte-stimulating hormone (MSH)

Question 3

Describe the principal action of Human growth hormone (hGH)

Answer 3

Stimulates liver (and other tissues) to synthesis and secrete insulin like growth factors 
Promotes growth of body cells, protein synthesis, tissue repair, lipolysis and elevation of blood glucose concentration

Question 4

Describe the principal action of Thyroid stimulating hormone (TSH)

Answer 4

Stimulates synthesis and secretion of thyroid hormones by thyroid gland

Question 5

Describe the principal action of Follicle-stimulating hormone (FSH)

Answer 5

In females, initiates development of oocytes and induces ovarian secretion of oestrogens
In males stimulates testes to produce sperm

Question 6

Describe the principal action of Luteinising hormone (LH)

Answer 6

Females: stimulates secretion of oestrogens and progesterone, ovulation and formation of corpus luteum
Males: stimulates testes to produce testosterone

Question 7

Describe the principal action of Prolactin (PRL)

Answer 7

Promotes milk production by mammary glands

Question 8

Describe the principal action of Adrenocorticotropic hormone (ACTH)

Answer 8

Stimulates secretion of glucocorticoids (cortisol) by adrenal cortex

Question 9

Describe the principal action of Melanocyte-stimulating hormone (MSH)

Answer 9

Unknown role in humans may influence brain activity (cause darkening of skin)

Question 10

Describe the principal action of oxytocin (OT)

Answer 10

Stimulates contraction of smooth muscle cells of uterus during childbirth
Stimulates contraction of myoepithelial cells in mammary glands to cause milk ejection

Question 11

Describe the principal actions of Antidiuretic hormone (ADH)

Answer 11

Conserves body water by decreasing urine volume
Decreases water lose
Raises blood pressure by constricting arterioles

Question 12

What makes up the anterior pituitary, describe

Answer 12

Epithelial tissue

Regulated by neurosecretory cells and negative feedback

Question 13

What makes up the posterior pituitary, describe

Answer 13

Neural tissue
Does not synthesise hormones it does store and release two hormones
Consists of axons and axon terminals

Question 14

What are the actions of thyroid hormones

Answer 14

• Increase basal metabolic rate (rate of oxygen consumption)
• Stimulates synthesis of sodium-potassium pumps
• Regulates metabolism
• Enhances actions of catecholamines
• Accelerate body growth

Question 15

How is thyroid hormone secretion controlled

Answer 15

• Low blood levels of T3 and T4 stimulates hypothalamus to secrete TRH
• TRH enters the hypophyseal portal veins flow to the anterior pituitary where it stimulates Thyrotrophs to secrete TSH
• TSH stimulates all aspects of thyroid follicular cell activity
• Thyroid follicular cells are released until normal
• An elevated number of T3 inhibits release of TRH and TSH (negative feedback)

Question 16

How is Calcitonin secretion controlled

Answer 16

• High blood levels of calcium ions stimulate secretion

- Low blood levels inhibit secretion