Chapter 10: Micromineral (Iodine)

Question 1

required as a component of thyroid hormone, thyroxine (t4) and triiodothyronine (t3)

Answer 1

iodine

Question 2

2 thyroid hormones

Answer 2

thyroxine; triiodothyronine

Question 3

thyroid hormone (t4)

Answer 3

thyroxine

Question 4

thyroid hormone (t3)

Answer 4

triiodothyronine

Question 5

dietary iodine is in the form of

Answer 5

iodide

Question 6

iodine - functions

a part of the _____

essential in regulating body’s growth, development, and metabolic rate

Answer 6

thyroid hormone

Question 7

iodine - functions

_____ and _____ are required for normal energy metabolism, thermoregulation, and intermediary metabolism

Answer 7

thyroxine and triiodothyronine

Question 8

iodine - functions

essential in the conversion of _____ to vitamin a

Answer 8

carotene

Question 9

iodine - functions

protein synthesis, carbohydrate production, rbc production, nerve muscle function

Answer 9

-

Question 10

iodine - absorption and metabolism

iodine is absorbed mainly in the _____, distributed in the extracellular fluids

Answer 10

small intestine

Question 11

iodine - absorption and metabolism

reduced first to the absorbable _____; absorbed iodide is converted to iodine before it enters the circulatory system

Answer 11

iodide

Question 12

iodine - absorption and metabolism

1/3 of the absorbed iodide in the blood is taken up by the _____ for synthesis of the thyroid hormones thyroxine (t4) and triiodothyronine (t3)

Answer 12

thyroid gland

Question 13

iodine - absorption and metabolism

t3 and t4 circulate in the bloodstream bound to thyroxine binding globulin, prealbumin, and albumin

_____ is biologically more potent than _____

Answer 13

t3; t4

Question 14

iodine - absorption and metabolism

the release of the t3/t4 by the thyroid is usually at a ratio of _____

this ratio is decreased when there is lack of iodine

Answer 14

20/1

Question 15

iodine - absorption and metabolism

the rest of the iodide is excreted in the _____, some amounts are lost via the skin and feces

Answer 15

urine

Question 16

iodine - absorption and metabolism

the metabolism of iodine occurs under the _____

Answer 16

hormonal feedback control

Question 17

iodine - absorption and metabolism

the uptake, synthesis, and release of iodine by the thyroid gland is stimulated by _____ released by the anterior pituitary gland

Answer 17

thyroid stimulating hormone

Question 18

iodine - interrelationship with other nutrients

from cabbage, kale, cauliflower, broccoli, turnip, brussel sprouts, and mustard greens

are substances that interferes with iodine metabolism inhibiting hormogenesis

Answer 18

goitrogens

Question 19

iodine - interrelationship with other nutrients

the goitrogens that affect iodide uptake by the thyroid glans, organification of the iodide or hormone release from the thyroid cells:

halide ions: bromide (br)
astatide (at-)
thiocyanate (SCN-)

Answer 19

-

Question 20

iodine - interrelationship with other nutrients

cassava contains _____ with thiocyanates as metabolites

Answer 20

cyanogen glucosides

Question 21

iodine - food sources

iodized salt, seafoods, seaweeds

Answer 21

iodine

Question 22

iodine - deficiency

most common forms of iodine deficiency are: _____ and _____

Answer 22

endemic goiter and cretinism

Question 23

iodine - deficiency

lack of iodine results in an enlargement of the _____ (goiter)

Answer 23

thyroid gland

Question 24

iodine - deficiency

enlargement of thyroid gland is due to over stimulation of the thyroid by _____ and _____, which are present in increased levels in an attempt to produce more circulating t3 and t3

Answer 24

TRF and TSH
thyrotropin-releasing factor;
thyroid-stimulating hormone

Question 25

iodine - deficiency

developmental defect in infants characterized by a dry thick skin, puffy face, and eyelids, enlarge tongue, husky voice, decreased reproductive ability, and mental retardation

Answer 25

cretinism

Question 26

iodine - toxicity

also known as Grave’s disease or exophthalmic goiter

increased basal metabolism, goiter, and disturbances in the autonomic nervous systems causing hyper irritability and increased creatinine metabolism

Answer 26

hyperthyroidism

Question 27

hyperthyroidism is also known as

Answer 27

grave’s disease or exophthalmic goiter

Question 27

iodine - deficiency

severe iodine deficiency can produce _____ which is characterized by a dry, waxy type swelling, with abnormal deposits of mucoproteins under the skin

Answer 27

myxedema

Question 28

iodine - recommended intake

for infants to children (0-5 years old) both male and female

Answer 28

90 ug

Question 29

iodine - recommended intake

for children (6-12 years old) both male and female

Answer 29

120 ug

Question 30

iodine - recommended intake

for children and adults (13->70 years old) both male and female

Answer 30

150 ug

Question 31

iodine - recommended intake

for pregnant and lactating

Answer 31

150 +100

Question 32

iodine - recommended intake

the recommended intake for adult corresponds to the intake necessary to maintain _____ level above the critical limit likely to be associated with the onset of goiter

it corresponds to the daily iodine urinary excretion of _____ ug/L

Answer 32

plasma iodide; 100 ug/L

Question 33

pregnant and lactating mothers

Answer 33

at risk of developing iodine deficiency