The endocrine system

Question 1

Includes all the organs that release chemical signals that circulate in the blood (hormones and neurohormones)

Answer 1

endocrine system

Question 2

What are the 3 major classes of hormone?

Answer 2

steroid, protein and peptide, amine hormones

Question 3

-are derived from cholesterol and are nonpolar and lipid-soluble.
- can diffuse freely across membranes

Answer 3

steroid hormones

Question 4

where are the steroid hormone receptors found?

Answer 4

within the ICF of target cells

Question 5

are steroid hormones stored within endocrine cells? why or why not?

Answer 5

No, they are synthesized and released on demand

Question 6

Their amino acid sequences are specified by genes, which are transcribed and translated. After synthesis, they undergo processing in which their structure is modified. (type of hormone)

Answer 6

protein and peptide hormone

Question 7

newly synthesized structure made from protein and peptide hormones? and what does it contain?

Answer 7

preprohormone; a signal peptide

Question 8

What does the signal peptide do in the preprohormone?

Answer 8

directs synthesis to the ER rather than the cytosol.

Question 9

once the signal peptide is removed from the preprohormone it becomes a what? which is??

Answer 9

prohormone; inactive

Question 10

What happens to the prohormones? Where do they go?

Answer 10

they are packaged into vesicles within the golgi apparatus

Question 11

receptors of this hormone are embedded in target cell membranes

the hormones are water-soluble and cannot cross membranes.

Answer 11

protein and peptide hormones

Question 12

derived from the amino acids tyrosine or tryptophan.
- properties vary
-typically stored after synthesis and released when endocrine cell is stimulated

Answer 12

amine hormones

Question 13

What is the primary determinant of the strength and duration of the target cell response?

Answer 13

conc of hormone in the ECF

Question 14

What is hormone concentration determined by?

Answer 14

1. rate of release from endocrine cells
2. rate of removal from the ECF

Question 15

The rate of removal is normally ________. While the rate of release ______ and is regulated by sensory receptors.

Answer 15

constant; varies

Question 16

an expression of the persistence of a hormone within the ECF

Answer 16

Half-life

Question 17

the amount of time it takes for half of hormone molecules to be removed from the blood

Answer 17

half-life

Question 18

Half-life varies between __________ and can be influenced by its ________ ____ ___________ in the blood.

Answer 18

hormones; mode of transport

Question 19

How does a carrier protein effect half-life?

Answer 19

if a hormone is bound to a carrier protein, its half-life is extended considerably

Question 20

increase the solubility of nonpolar hormones, allowing increased conc of these hormones in the ECF.

Answer 20

carrier proteins

Question 21

small region within the inferior part of the brain

Answer 21

hypothalamus

Question 22

the hypothalamus is connected to the pituitary gland by a narrow stalk called the

Answer 22

infundibulum

Question 23

The pituitary gland is divided into two lobes called the _________ and ___________ lobes

Answer 23

anterior; posterior

Question 24

this lobe is made of neural tissue; the other lobe is made of endocrine cells

Answer 24

posterior lobe; anterior lobe

Question 25

made of neurosecretory cell axon terminals and associated capillary networks.

Answer 25

posterior lobe

Question 26

the cell bodies of the neurosecretory cells are located within the hypothalamus and are localized in two clusters:

Answer 26

paraventricular nucleus (PVN) and the supraoptic nucleus (SON)

Question 27

PVN and SON produce the peptide hormones ____ and ____________

Answer 27

oxytocin and anti-diuretic hormone (ADH)

Question 28

best known for its effect during childbirth and lactation (in humans)

Answer 28

oxytocin

Question 29

regulates blood vol thru its effects on the kidneys.

Answer 29

ADH

Question 30

These hormones are released from axon terminals within the posterior lobe

Answer 30

oxytocin and ADH

Question 31

Made of endocrine cells and produces six different hormones

Answer 31

anterior lobe

Question 32

What are the two categories of hormones released by the anterior lobe?

Answer 32

direct-acting hormones and tropic hormones

Question 33

What are the two direct-acting hormones? What does it mean by direct-acting?

Answer 33

growth hormone (GH) and prolactin; they exert their effects on non-endocrine organs.

Question 34

regulates growth and nutrient metabolism in many tissues, particularly fat and skeletal muscle.

Answer 34

growth hormone (GH)

Question 35

stimulates milk synthesis in lactating females

Answer 35

prolactin

Question 36

What are the four tropic hormones?

Answer 36

adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid stimulating hormone (TSH).

Question 37

What does it mean by tropic hormones?

Answer 37

they regulate the functions of other endocrine organs

Question 38

affects glucocorticoid hormone production in the adrenal cortex

Answer 38

ACTH adrenocorticotropic hormone

Question 39

affect sex hormone and gamete production in the gonads

Answer 39

LH luteinizing hormone and FSH follicle-stimulating hormone

Question 40

affects thyroid hormone production in the thyroid glands

Answer 40

TSH thyroid stimulating hormone

Question 41

What is hormone production by the anterior lobe regulated by?

Answer 41

neurohormones produced by the hypothalamus

Question 42

What makes the cells from the anterior lobe diff from those that produce ADH and oxytocin?

Answer 42

-neurosecretory cells are located within hypothalamus -neurohormones released into **portal veins**

Question 43

carry blood directly to anterior lobe (part of special capillary network)

Answer 43

portal veins