Homeostasis - Intro to Endocrine System + Hormones

Question 1

Nervous regulation

Answer 1

• Involves nerve impulses (electrical)
• Impulses transmitted by neurons
• Fast
• Responses are short lived
• May be voluntary or involuntary
• Usually localized

Question 2

Endocrine Regulation

Answer 2

• Involves hormones (chemical impulses)
• Hormones transported by blood
• Slow
• Responses short lived or long lived
• Always involuntary
• Tend to affect more than one target organ

Question 3

Steroid hormones

Answer 3

• Made from cholesterol (lipid)
• Soluble in fat
• Usually pass through cell membrane, acting on receptors inside cell
• Includes hormones such as cortisol + sex hormones

Question 4

Peptide (protein) hormones

Answer 4

• Made from chains of amino acids of varying length
• Soluble in water
• Act on cell membrane receptors
• Includes hormones such as growth factor + insulin

Question 5

Steroid hormone reponse

Answer 5

1. Hormone passes through cell membrane, entering cytosol
2. Hormone combines with receptor molecule in cytosol or nucleus
3. Steroid-receptor complex activates gene in cell nucleus of target cell
4. Specific protein is produced

Question 6

Peptide hormone response

Answer 6

1. Hormone binds with specific receptor on cell membrane
2. Receptor changes shape, activating signal that is passed into cell
3. Signal pathway causes further changes in cell such as activation/deactivation of proteins

Question 7

Growth hormone (GH)

Answer 7

• Anterior lobe of pituitary gland
• Target: bone, soft tissue
• Function: stimulates growth of bones + soft tissues, helps control metabolism of glucose + other nutrients

Question 8

Prolactin (PRL)

Answer 8

• Anterior lobe of pituitary gland
• Target: mammary glands
• Function: stimulates breast development + milk production

Question 9

Luteinizing hormone (LH)

Answer 9

• Anterior lobe of pituitary gland
• Target: ovaries, testes
• Function: regulates ovulation in females + secretion of sex hormones in males

Question 10

Follicle stimulating hormone (FSH)

Answer 10

• Anterior lobe of pituitary gland
• Target: ovaries, testes
• Function: stimulates egg growth and development + secretion of sex hormones in females, stimulates sperm production in males

Question 11

Adrenocorticotropic hormone (ACTH)

Answer 11

• Anterior lobe of pituitary gland
• Target: adrenal cortex
• Function: stimulates secretion of glucocorticoids by adrenal cortex, helping to regulate fluid balance + to cope with stress

Question 12

Thyroid stimulating hormone (TSH)

Answer 12

• Anterior lobe of pituitary gland
• Target: thyroid gland
• Function: stimulates secretion of thyroid hormones + growth of thyroid gland

Question 13

Antidiuretic hormone (ADH)

Answer 13

• Posterior lobe of pituitary gland
• Target: kidneys
• Function: increases blood volume + pressure by increasing water reabsorption in kidneys

Question 14

Oxytocin

Answer 14

• Posterior lobe of pituitary gland
• Target: uterus, mammary glands
• Function: promotes uterine contractions, stimulates milk release from breasts