Endocrine System

Question 1

Cataract

Answer 1

clouding of the lens

Question 2

Retina (neural)

Answer 2

ora serrata - anterior margin

Question 3

Macula lutea (neural)

Answer 3

central patch for detailed vision

fovea centralis: pit within the macula

Question 4

Optic nerve exits at optic disc. What is optic disc?

Answer 4

disc is a blind spot without receptors

Question 5

Macular degeneration:

Answer 5

death of receptor cells in the macula lutea

Question 6

Image formation:

Answer 6

for DISTANT vision (over 20ft), lens is flat
for NEAR vision, lens thickens by accommodation
visual defects often involve image formation

Question 7

How does LASIK vision correction work?

Answer 7

1. cornea is sliced with sharp knife and flap of cornea is reflected so deeper corneal layers are exposed
2. laser removes microscopic portions of the deeper corneal layers and changes shape of cornea
3. corneal flap is put back into place and edges of the flap fuse within 72 hours

Question 8

Rods

Answer 8

night (scotopic) vision, monochromatic

uses rhodopsin as pigment

Question 9

Cones

Answer 9

day (phototropic) vision, trichromatic

uses photopsins as 3 different pigments

Question 10

Structure of retina: interneuron bipolar cells

Answer 10

receive input from rods and cones

Question 11

Structure of retina: ganglion cells

Answer 11

receive input from bipolar cells, they are axons from optic nerve

Question 12

Ganglion cell axons make up ___

Answer 12

optic nerve, optic chiasm, and optic tract

Question 13

Chiasm is ___

Answer 13

hemidecussation (partial crossing over of nerve fibers in the optic chiasm)

Question 14

Lateral geniculate nucleus of thalamus:

Answer 14

axons of these cells form optic radiations (cerebral white matter)

Question 15

Primary visual cortex is in the __

Answer 15

occipital lobe

Question 16

Endocrine vs. Exocrine

Answer 16

endocrine glands are ductless and secrete internally, exocrine glands secrete on body surface

Question 17

Hormones:

Answer 17

chemical messengers secreted into bloodstream

stimulate responses in distant targets

secreted by endocrine glands or specialized cells in other organs

Question 18

Endocrine system vs. Nervous system

Answer 18

endocrine effects are slower and long-lasting

can affect a wider variety of more distant targets

the two systems coordinate responses, and some cells are “neuroendocrine cells”

Question 19

Adenohypophysis:

Answer 19

anterior lobe and pars tuberalis

Question 20

Hypophyseal portal system

Answer 20

blood vessel from the anterior pituitary connection to the hypothalamus

Question 21

Neurohypophysis:

Answer 21

posterior lobe, stalk (infundibulum), and median eminence

Question 22

Neurohypophysis connection to hypothalamus:

Answer 22

consists of nervous (not glandular) tissue that includes axons of hypothalamic neurons from the hypothalamo-hypophyseal tract

Question 23

Hormone-secreting cells in anterior pituitary:

Answer 23

acidophils and basophils

Question 24

Acromegaly

Answer 24

excess growth hormone secretion after puberty

Question 25

Pituitary dwarfism:

Answer 25

hyposecretion of growth hormones in childhood

Question 26

Pineal gland (epiphysis cerebri) characteristics:

Answer 26

1. at roof of third ventricle 2. posterior end of corpus callosum 3. secretion peaks from 1-5 years of age 4. shrinks by 75% (involution) at puberty 5. secretes melatonin and plays role in circadian rhythm and mood

Question 27

Thymus characteristics:

Answer 27

1. bilobed gland in mediastinum, superior to heart 2. large in fetus and infants, involutes at age 14 3. maturation of certain white blood cells (t-cells) 4. hormones stimulate the development of lymphatic organs and t-cells (thymopoietin, thymosin, and thymulin)

Question 28

Thyroid gland characteristics:

Answer 28

1. two lobes are joined by isthmus, adjacent to trachea 2. thyroid follicles are sacs with follicular cells 3. releases thyroid hormones T3 and T4 which raise metabolic rate, and calcitonin from C-cells

Question 29

Parathyroid gland characteristics:

Answer 29

1. four small ovoid glands posterior side of thyroid 2. variable in location, size, and number 3. secretes parathyroid hormones (PTH) from chief cells to raise calcium in blood

Question 30

Endemic Goiter:

Answer 30

dietary iodine deficiency, feedback loop in effort to make more thyroid hormones

Question 31

Graves Disease:

Answer 31

autoimmune disorder, autoantibodies mimic the effect of TSH on the thyroid causing hypersecretion

Question 32

Adrenal gland (suprarenal gland) characteristics:

Answer 32

1. superior to kidneys, retroperitoneal 2. contains adrenal medulla and adrenal cortex

Question 33

Adrenal medulla characteristics:

Answer 33

1. 10-20% of gland, central part 2. chromaffin cells secrete epinephrine, norepinephrine, and dopamine 2. raises metabolic rate, mobilizes energy

Question 34

Adrenal cortex characteristics:

Answer 34

1. 80-90% of gland, outer part 2. secretes more than 25 corticosteroids including mineralocorticoids, glucocorticoids, and sex steroids

Question 35

Adrenal cortex: zona glomerulosa

Answer 35

most superficial layer

Question 36

Adrenal cortex: zona fasciculata

Answer 36

intermediate, thick layer

Question 37

Adrenal cortex: zona reticularis

Answer 37

deepest cortical layer

Question 38

Cushing syndrome:

Answer 38

ACTH oversecretion by the anterior pituitary gland, excess glucocorticoid secretion by the adrenal cortex

Question 39

Adrenogenital syndrome:

Answer 39

adrenal cortex lacks enzymes needed to make cortisol and aldosterone, adrenal androgen hypersecretion

Question 40

Pancreatic islets:

Answer 40

also called islets of Langerhands alpha, beta, and delta cells

Question 41

alpha cells:

Answer 41

glucagon causes rise in blood sugar

Question 42

beta cells:

Answer 42

insulin causes absorption of blood sugar, amylin enhances insulin effects

Question 43

delta cells:

Answer 43

somatostatin regulates speed of digestion

Question 44

Gonads: Ovaries

Answer 44

granulosa cells of the follicle secrete estrogen corpus luteum secretes progesterone inhibin inhibits FSH secretion

Question 45

Gonads: Testes

Answer 45

Interstitial cells: testosterone regulates sex drive and sperm production Substentacular cells: inhibin inhibits FSH secretion

Question 46

Endocrine cell of liver:

Answer 46

angiotensinogen

Question 47

Endocrine cell of kidneys:

Answer 47

renin and erythropoietin (EPO)

Question 48

Endocrine cell of heart:

Answer 48

natriuretic peptides

Question 49

Endocrine cell of stomach:

Answer 49

ghrelin

Question 50

Endocrine cell of adipose tissue:

Answer 50

leptin

Question 51

Aging of endocrine system:

Answer 51

1. adrenal, thymus, and pineal gland all shrink in size early in life 2. insulin secretion and effectiveness decline in old age 3. ovarian decline at menopause increase risk of cardiovascular disease, osteoporosis, and dementia 4. thyroid effectiveness declines in the elderly, less target cell ability to convert T4 into T3