Intro to Endocrine System

Question 1

What is autocrine signaling?

Answer 1

The hormone secreted from one cell type effects the same cell or the same type of cell.

Question 2

What is paracrine signaling?

Answer 2

The hormone secreted from one cell type effects a different type of cell.

Question 3

What is endocrine signaling?

Answer 3

The hormone secreted from one cell type travels through the bloodstream before effecting a cell of a different type.

Question 4

What is neuroendocrine signaling?

Answer 4

The hormone secreted from a neuron travels through the bloodstream to affect a cell of a different type.

Question 5

What hormones does the hypothalamus secrete? (6)

Answer 5

TRH, CRH, GnRH, GHRH, Somatostatin, and Dopamine

Question 6

What hormones does the anterior pituitary secrete? (7)

Answer 6

TSH, FSH, LH, ACTH, MSH, Growth Hormone, and Prolactin

Question 7

What hormones does the posterior pituitary secrete? (2)

Answer 7

Oxytocin and ADH

Question 8

What hormones does the thyroid release? (3)

Answer 8

T3, T4, and Calcitonin

Question 9

What hormone does the parathyroid release? (1)

Answer 9

PTH

Question 10

What hormones does the pancreas release? (2)

Answer 10

Insulin and Glucagon

Question 11

What hormones does the adrenal medulla release? (2)

Answer 11

Norepinephrine and Epinephrine

Question 12

What hormones does the kidney release? (2)

Answer 12

Renin and 1,25-Dihydroxycholecalciferol

Question 13

What hormones does the adrenal cortex release? (3)

Answer 13

Cortisol, Aldosterone, and Adrenal androgens

Question 14

What hormone does the testes release? (1)

Answer 14

Testosterone

Question 15

What hormones do the ovaries release? (2)

Answer 15

Estradiol and Progesterone

Question 16

What hormones does the corpus luteum release? (2)

Answer 16

Estradiol and Progesterone

Question 17

What hormones does the placenta release? (4)

Answer 17

HCG, Estriol, Progesterone, and hPL

Question 18

What is the sequence of peptide hormone synthesis?

Answer 18

DNA>mRNA>preprohormone (in ER)>prohormone (golgi apparatus)>hormone (secretory vesicles)

Question 19

Proteolytic enzymes cleave to form a ______ ______.

Answer 19

Functional hormone

Question 20

An endocrine cell stimulus such as increased intracellular _____ or increased _____ and ____ activation, cause release of peptide hormone.

Answer 20

calcium; cAMP; PKA

Question 21

______ hormones are synthesized and secreted by the adrenal cortex, gonads, corpus luteum, and placenta.

Answer 21

Steroid

Question 22

____ hormones are derived from tyrosine.

Answer 22

Amine

Question 23

______ are synthesized in the cytosol and secretory granules and act through cell-membrane associated receptors.

Answer 23

Catecholamines

Question 24

Thyroid hormones are synthesized by thyroid gland and stored as ______ in follicles within the gland.

Answer 24

thyroglobulin

Question 25

Thyroid hormones cross the cell membrane and act through _____ _____.

Answer 25

nuclear receptors

Question 26

The more protein binding, the _____ the plasma half life and the _____ the metabolic clearance (for the most part).

Answer 26

longer; slower

Question 27

The ______ mechanism of hormone secretion is where neuronal input increases or decreases hormonal stimulation.

Answer 27

neural

Question 28

The feedback mechanisms of hormone secretion is when some element of the pathway feeds back, directly or indirectly, on the endocrine gland to change _____ ____.

Answer 28

secretion rate

Question 29

_____ endocrine feedback is when some feature of hormone action causes additional secretion of the hormone.

Answer 29

Positive

Question 30

Examples of positive endocrine feedback include _____ and ____ _____.

Answer 30

ovulation; labor contractions

Question 31

______ endocrine feedback is when some feature of hormone action inhibits further secretion of the hormone.

Answer 31

Negative

Question 32

______ endocrine feedback confers stability by keeping a physiological parameter within a normal range.

Answer 32

Negative

Question 33

____-loop feedback is when a hormone released from a peripheral endocrine gland feeds back all the way to the hypothalamus and pituitary.

Answer 33

Long

Question 34

____-loop feedback is when a hormone secreted from the pituitary feeds back to the hypothalamus.

Answer 34

Short

Question 35

____ ____-loop feedback is when a gland inhibits its own secretion.

Answer 35

Ultra short

Question 36

Descending and ascending neuronal inputs modulate hormonal secretion from the ______.

Answer 36

hypothalamus

Question 37

The _______ ______ imposes a circadian rhythm on the secretion of hypothalamic releasing hormones and endocrine axes.

Answer 37

suprachiasmatic nucleus (SCN)

Question 38

The _____ _____ releases melatonin which feedbacks to the SCN information about day-night.

Answer 38

pineal gland

Question 39

______ _____ influences the release of hormone from the hypothalamus.

Answer 39

Physiological stress

Question 40

Regulation of hormone receptors is influenced by the _____-_____ complex and by responsiveness of target tissue which is expressed in a ____-____ relationship.

Answer 40

hormone-receptor; dose-response

Question 41

Sensitivity of a hormone receptor is defined as hormone concentration that produces __% of maximal response.

Answer 41

50

Question 42

Responsiveness can be changed by changing the _____ of receptors or changing the _____ of the receptors for the hormone.

Answer 42

number; affinity

Question 43

__-_____ is the increase in the number of receptors or sensitivity of target tissue when hormone levels are low.

Answer 43

Up-regulation

Question 44

__-_____ is the reduction in the number of receptors or the sensitivity of target tissue when hormone levels are chronically high.

Answer 44

Down-regulation

Question 45

What are the first messengers in the adenylyl cyclase mechanism? (5)

Answer 45

ACTH, LH, FSH, TSH, and glucagon

Question 46

What is the primary effector in the adenylyl cyclase mechanism?

Answer 46

adenylyl cyclase

Question 47

What is the second messenger in the adenylyl cyclase mechanism?

Answer 47

cAMP which cleaves to 5'AMP (inactive)

Question 48

What is the secondary effector in the adenylyl cyclase mechanism?

Answer 48

PKA

Question 49

What are the first messengers in the phospholipase C mechanism? (3)

Answer 49

GnRH, TRH, and oxytocin

Question 50

What is the primary effector in the phospholipase C mechanism?

Answer 50

phospholipase C

Question 51

What are the second messengers in the phospholipase C mechanism? (3)

Answer 51

IP3, DAG, and Ca2+

Question 52

What is the secondary effector in the phospholipase C mechanism? (2)

Answer 52

PKC or calmodulin

Question 53

Only ____ steroid hormones can diffuse into the target cells.

Answer 53

unbound

Question 54

Steroid hormone receptors are located in the _____ or _____.

Answer 54

cytoplasm; nucleus

Question 55

The steroid receptor-hormone complex binds to DNA and activates or represses on or more genes. The activated genes create new ____ and that moves back to the _____.

Answer 55

mRNA; cytoplasm

Question 56

Some steroid hormones also bind to membrane receptors that use second messenger systems to create ____ ____ _____.

Answer 56

rapid cellular responses

Question 57

Guanylyl cyclase activation converts ___ to ___.

Answer 57

GTP; cGMP

Question 58

cGMP activates ___ _____ which results in relaxation of vascular smooth muscle by ____ ____.

Answer 58

cGMP kinases; nitric oxide

Question 59

Tyrosine kinases phosphorylates downstream proteins. What are the two types of tyrosine kinases?

Answer 59

Receptor tyrosine kinases (RTKs) and tyrosine kinase-associated receptors

Question 60

RTKs are the intrinsic tyrosine kinase activity and include ____ ____ ____ receptor and _____ receptor.

Answer 60

nerve growth factor; insulin

Question 61

Tyrosine kinase-associated receptors associate non-covalently to proteins that have kinase activity and include ____ ____ receptors.

Answer 61

growth hormone