Chapter 26- Endocrine Glands

Question 1

What is prolactin and its main function?

Answer 1

PRL- non tropic

Stimulates and maintains milk production

Operates on a positive feedback loop

ANTERIOR PITUITARY

Question 2

What is thyroid stimulating hormone?

Answer 2

TSH- tropic

Causes thyroid to create thyroid hormone

ANTERIOR PITUITARY

Question 3

What is adrenocorticotropic hormone?

Answer 3

ACTH- tropic

Stimulates adrenal cortex to secrete hormones

ANTERIOR PITUITARY

Question 4

What is released by the hypothalamus to control the pituitary gland?

Answer 4

Secrete releasing hormones

Question 5

What is gonadotropic hormone?

Answer 5

Follicle stimulating hormone- FSH

Regulates activity of gonads

Stimulates follicle cells and evolvement to secrete estrogen and develop ovaries (female)

Stimulates sperm development (male)

Luteinizing hormone- LH

Triggers ovulation and releases eggs (female)

Stimulates testosterone production (male)

Question 6

Can the posterior pituitary create the hormones it secretes?

Answer 6

No. Unlike the anterior pituitary, the posterior pituitary can only store hormones then release

Question 7

What is growth hormones main function?

Answer 7

GH (non tropic)

General metabolic hormone

Causes amino acids to build into proteins

Causes fats to break down into energy

ANTERIOR PITUITARY

Question 8

What controls the anterior pituitary?

Answer 8

The hypothalamus responds to sensory information by secrete releasing hormones

Will stimulate or inhibit hormone production in pituitary

Links nervous system and endocrine system through pituitary

Question 9

What is antidiuretic hormone and what is its purpose?

Answer 9

ADH

Inhibits urine production, helps body retain water

Causes vasoconstriction of blood vessels, increasing blood pressure (large amounts)

If not working can cause diabetes insipidus

POSTERIOR PITUITARY

Question 10

What is oxytocin and what is its purpose?

Answer 10

OT

causes milk ejection (positive feedback) triggered by feeding infant

Stimulates contraction of uterine muscles during birth (positive feedback) triggered by uterine stretching

POSTERIOR PITUITARY

Question 11

What are the two hormones produces by the thyroid gland?

Answer 11

Thyroid hormone

Calcitonin

Question 12

What is thyroid hormone and what is its purpose?

Answer 12

Divided into two types of iodine containing hormones

T4- inactive in blood- stored and secreted by thyroid gland

T3- active state- converted from t4 at target destination to produce metabolic effect

Regulates metabolic rate
Regulates body temp
Controls cell growth

THYROID GLAND

Question 13

What happens if we have a lack of iodine?

Answer 13

Pituitary sends thyroid stimulating hormone (TSH) to thyroid, but thyroid does not have the iodine required to produce t4.

Pituitary keeps sending TSH, since no change occurs

Thyroid gets inflamed and no longer functions properly- goiter

Question 14

What is calcitonin and what is its purpose?

Answer 14

Decreases blood calcium levels by increasing osteoblasts

THYROID GLAND

Question 15

What is parathyroid hormone and what is its purpose?

Answer 15

PTH

Antagonist to calcitonin

Stimulates osteoclasts to remove calcium from bone

Stimulates kidneys and intestines to absorb more calcium

PARATHYROID GLAND

Question 16

What are the two important parts of the adrenal glands and what tissues are they made up of?

Answer 16

Adrenal cortex- endocrine tissue. Stimulates by ACTH

Adrenal medulla- neural tissue. Stimulates by SNS

Question 17

What are the three layers of the adrenal cortex?

Answer 17

Zona glomerulosa

Zona fasciculata

Zona reticularis

Question 18

What hormones does the Zona Glomerulosa secrete and what is their purpose?

Answer 18

Mineralocorticoids-

Aldosterone- maintains sodium homeostasis by causing reabsorption of sodium.

Absorption of sodium> reabsorption of water> blood vol increases> blood pressure increases

Ultimately regulates mineral content and electrolytes in body and regulates blood pressure.

Question 19

What is the fast acting loop that increases blood pressure? How does it work?

Answer 19

Renin-Angiotensin-Aldosterone System (RAAS)

Low BP signals kidney to release Renin (enzyme)

Renin activates Angiotensin, which then activates angiotensin II, which stimulates adrenal cortex

Adrenal cortex secretes aldosterone to increase water retention and increase BP

Question 20

What is are the hormones secreted by the Zona Fasciculata and what are their purpose?

Answer 20

Glucocorticoids- most importantly cortisol

Stimulated in response to ACTH released by anterior pituitary

Regulates long term stress response, accelerates lipid catabolism

Secreted in response to stress as a way of increasing glucose availability for fight or flight

Constant flow of cortisol> increased glucose> obesity, diabetes etc

Question 21

What hormones are secreted by the Zona reticularis and what is their purpose?

Answer 21

Gonadocorticoids-

sex hormones
Androgen- males
Estrogen- female

Question 22

What hormones does the adrenal medulla secrete and what are their purpose?

Answer 22

Catecholamines-

Epinephrine(Epi)
Norepinephrine (NE)

Short term stress response- stimulated by sympathetic nervous system

• increase heart rate
• increase blood pressure
• increase glucose levels
• dilate lung passageways

Question 23

Do both long term and short term stress responses both operate out of the pituitary?

Answer 23

No.

Short term stress is handled by epinephrine- released by nervous message sent by hypothalamus directly

Long term stress is detected by hypothalamus, sent to pituitary, then sent to adrenal gland which secretes aldosterone( increased blood volume and BP) or cortisol (increased glucose level)

-other effects of long term stress include

Increased heart rate, dilated pupils, blood redirected from skin and digestion to skeletal muscle, brain, and heart, and dilated trachea

Question 24

What is the endocrine portion of the pancreas and what does it secrete?

Answer 24

Islets of langerhans

Insulin (from beta cells)- increase blood glucose

Glucagon (from alpha cells)- decrease blood glucose

Question 25

Where is the thymus and what is its purpose?

Answer 25

Located I’m mediastinum (large in children- deteriorates with age)

Produces THYMOSIN- matures white blood cells and develops immune system

Question 26

Where is the pineal gland and what does it secrete?

Answer 26

Found in brain- (near hypothalamus)

Produces MELATONIN

• establishes sleep cycle and biological clock

Question 27

What is the purpose of testes and what hormone do they produce?

Answer 27

-produce male sex cells and sperm

Produces testosterone

• responsible for growth and maintenance of male sexual characteristics
• deep voice, hair growth, enlarged skeletal muscles, increased bone growth and density
• growth and maturation of reproductive system

Question 28

What are the two hormones produces by the ovaries and what do they do?

Answer 28

Progesterone- (secreted by corpus luteum)

• promotes pregnancy(maintains uterine lining)
• acts with estrogen to start menstruation
• placenta produces progesterone
• prepares body for lactation

Estrogen (secreted by Ovarian follicular cells)

• promotes development and maintenance of female sex characteristics
• increased hair, fat at hips, breasts, and widening at the hips
• prepares uterus for egg
• maintains pregnancy

Question 29

What is the hormone secreted in some parts of the small intestine and stomach?

Answer 29

Gastric- increases HCL which aids with digestion

Question 30

What is the hormone in the kidney that increases red blood cell production?

Answer 30

Erythropoietin (EPO)

Question 31

What is the hormone produced by the heart?

Answer 31

Atrial natriuretic hormone (ANH)

-promotes loss of sodium and water from body to decrease blood pressure