Chapter 7

Question 1

List the 3 general ways that a hormone can regulate the activity of its target cells.

Answer 1

1. by activating an enzyme
2. by activating a receptor that opens a channel
3. by acting as a transcription factor…turns on gene

Question 2

Describe the location of the receptors for lipid soluble hormones and water soluble hormones. Describe how these locations affect the way that a hormone (generally) regulates the activity of its target.

Answer 2

Water soluble hormone - Receptor always located outside the cell on the cell membrane. It activates enzymes and opens channels. (peptide/proteins - series of amino acids folded and epi/norepi)
Lipid soluble hormone - Receptor always located inside the cell (intracellular receptor) It activates transcription factors - turns on gene. (Steroid hormones and T3, T4 which act like steroid)

Question 3

How are hormones once released into the blood removed from the blood?

Answer 3

1. Enzymes in liver destroy them

2. You pee them out

Question 4

List the three classes of hormones. For each class of hormone describe its chemical structure and give some examples of specific hormones.

Answer 4

1. Peptide/ proteins - series of amino acids folded (insulin, parathyroid hormone)
2. Steroid hormones - all made form cholesterol; lipid soluble (estrogen, androgens, cortisol)
3. Amino Acid based - catecholamines and thyroid hormones (Catecholamines: epinephrine, norepinephrine, dopamine; Thyroid hormone: thyroxine T4 and T3)

Question 5

List the hormones of the posterior pituitary gland. For each describe its primary effects.

Answer 5

1. Oxytocin (peptide hormone) - uterine contraction and milk let down
2. ADH (Antidiuretic hormone) - “anti-pissing” hormone

Question 6

Describe how the secretion of the hormones of the posterior pituitary gland is regulated.

Answer 6

The hypothalamus produces and stores the hormones and delivers to the secretion site in the posterior pituitary gland (axons from cell bodies in the hypothalamus extend into the posterior pituitary gland)

Question 7

List the hormones of the anterior pituitary gland. For each describe its primary effects and list a/the primary target.

Answer 7

ACTH - (adrenocortictropic hormone) Target: adrenal cortex - increased production and release of cortisol
TSH - (thyroid stimulating hormone) Target: thyroid - production of the thyroid hormone.
FSH - (follicle stimulating hormone) Target: testis - follicle growth and sperm production
LH - (luteinizing hormone) Target: ovary - causes ovaries to release an egg during ovulation
GH - (growth hormone) Target: bone, muscle, adipose tissue - stimulates growth
PRL - (prolactin) Target: mammary gland - signals milk production

Question 8

Define the term trophic hormone. Explain how this term is used in physiology. List the major tropic hormones.

Answer 8

Trophic hormones - hormones that control the secretion of other hormones.
They cause secretion in endocrine glands
Major trophic hormones: ACTH, TSH, FSH, LH, GH