Chapter 13: The Endocrine System

Question 1

negative feedback

Answer 1

control mechanism in which rising level of a hormone leads to a decrease in hormone secretion

Question 2

3 methods of negative feedback

Answer 2

• tropic hormones
• nervous system control
• changes in composition of internal environment

Question 3

tropic hormones

Answer 3

act on other glands, to regulate their hormone secretion

Question 4

nervous system control

Answer 4

nervous system directly stimulate some glands to secrete their hormones

Question 5

changes in composition of internal environment

Answer 5

changes levels of specific substances in the blood stimulates or inhibits secretion of certain hormones

Question 6

what controls hormone secretion?

Answer 6

various negative feedback mechanisms

Question 7

pituitary gland

Answer 7

• lies at the base of brain, in sella turcica of sphenoid bone
• attached to hypothalamus by pituitary stalk

Question 8

pituitary stalk is also called…

Answer 8

infundibulum

Question 9

2 portions of pituitary gland

Answer 9

1. anterior (adenohypophysis)
2. posterior (neurohypophysis)

Question 10

does the posterior portion of the pituitary gland produce hormones?

Answer 10

no

Question 11

anterior lobe regulation

Answer 11

hypothalamic releasing hormones are transported through the Hypophyseal Portal System, and stimulate cells of anterior lobe to release hormones

Question 12

posterior lobe regulation

Answer 12

nerve impulses from hypothalamus travel through the infundibulum & stimulate nerve endings in posterior lobe to release hormones

Question 13

anterior pituitary hormones

Answer 13

released in response to a releasing hormone from the hypothalamus; some inhibited by inhibiting hormones from the hypothalamus

Question 14

examples of anterior pituitary hormones

Answer 14

• growth hormone (GH)
• prolactin (PL)
• thyroid stimulating (TSH)
• adrenocorticotropic (ACTH)
• follicle stimulating (FSH)
• luteinizing (LH)

Question 15

gigantism

Answer 15

excess GH while growth plates open

Question 16

dwarfism

Answer 16

inadequate GH while growth plates open`

Question 17

thyroid hormone

Answer 17

controls metabolism

Question 18

how is TSH secretion controlled?

Answer 18

• by the level of thyrotropin releasing hormone (TRH) from the hypothalamus
• negative feedback by thyroid hormones, the final hormones

Question 19

posterior pituitary hormone

Answer 19

2 hormones are produced by neurons in the hypothalamus, and stored and released by posterior pituitary gland

Question 20

how are the hormones produced in hypothalamus transported to posterior pituitary gland?

Answer 20

pituitary stalk; infundibulum

Question 21

two types of posterior pituitary hormones

Answer 21

1. antidiuretic hormone (ADH)
2. oxytocin (OT)

Question 22

antidiuretic hormone

Answer 22

decreases urine production by removing volume of H2O the kidneys excrete; also causes vasoconstriction to increase blood pressure

Question 23

oxytocin

Answer 23

also called the love hormone; causes muscle contraction in uterine wall during childbirth, milk ejection during lactation, and boosts testosterone in men

Question 24

thyroid gland

Answer 24

• has two lateral lobes, connected by isthmus
• lies below larynx, anterior & lateral to trachea
• has special ability to remove iodine from blood
• produces 3 hormones

Question 25

three hormones produced by thyroid gland

Answer 25

1. T4
2. T3
3. calcitonin

Question 26

T4

Answer 26

thyroxine

Question 27

T3

Answer 27

triiodothyronine

Question 28

petocin

Answer 28

used to induce women into labor

Question 29

what cells produce T3 & T4

Answer 29

follicular cells

Question 30

what cells produce calcitonin?

Answer 30

extra or parafollicular cells

Question 31

what is the thyroid gland made of?

Answer 31

follicles

Question 32

follicles

Answer 32

round secretory units

Question 33

what surrounds each follicle?

Answer 33

a single layer of follicular cells

Question 34

what fills follicle cavities?

Answer 34

vicious colloid

Question 35

what lies outside follicles?

Answer 35

extra follicular (c) cells

Question 36

calcitonin

Answer 36

lowers blood calcium

Question 37

hyperthyroid

Answer 37

increased metabolism; hyperthyroidism, graves disease

Question 38

hypothyroid

Answer 38

decreased metabolism; hypothyroidism, Hashimoto’s, simple goiter