Week 12- Thyroid & Steroid hormones

Question 1

• —-causes increased metabolism, whereas —-causes decreased metabolism.
  a) Hypothyroidism
  b) Hyperthyroidism

Answer 1

b) Hyperthyroidism

a) Hypothyroidism

Question 2

Weight gain and cold intolerance are seen in —-. Whereas, sweating, weight loss and heat intolerance are seen in —–.

a) Hypothyroidism
b) Hyperthyroidism

Answer 2

a) Hypothyroidism

b) Hyperthyroidism

Question 3

• —reduces the basal metabolic rate (BMR), whereas, —-increases the BMR.
  a) Hypothyroidism
  b) Hyperthyroidism

Answer 3

a) Hypothyroidism

b) Hyperthyroidism

Question 4

• —could be associated with a deficiency in LPL activity. As a consequences, ——could be elevated.
  a) Hypothyroidism
  b) Hyperthyroidism
  c) LDL and VLDL
  d) HDL

Answer 4

a) Hypothyroidism

c) LDL and VLDL

Question 5

Goiter and cretinism are both happening due to lack of ——-

a) Calcium
b) Copper
c) Iodine
d) Iron
e) Potassium

Answer 5

c) Iodine

Question 6

Which of the following autoantibodies is most commonly associated with Hashimoto’s disease?

a) Anti TSH receptor antibodies
b) Anti TPO antibodies
c) Anti TBG antibodies
d) Anti thyroglobuin antibodies

Answer 6

b) Anti TPO antibodies

Question 7

• —-are formed during the organification of thyroglobulin, whereas ——-are formed during the coupling of iodotyrosine.
  a) T1 & T2
  b) T3 & T4
  c) T1 & T3
  d) T2 & T4
  e) T1 & T4

Answer 7

a) T1 and T2

b) T3 and T4

Question 8

Which of the following thyroid hormones has the highest biological activity?

a) T4
b) T3
c) rT3

Answer 8

b) T3

Question 9

Which of the following thyroid hormones is more abundant?

a) T4
b) T3
c) rT3

Answer 9

a) T4

Question 10

Thyroxine is —-, which is converted to the more active form, —-, when the target tissues need it.

a) T4
b) T3
c) rT3

Answer 10

a) T4

b) T3

Question 11

In thyroid hormones synthesis, T3 and T4 were synthesized inside thyroglobulin in the ——-and were released via lysosomes in the ——–.

a) Colloid region
b) Follicular cells
c) Plasma

Answer 11

a) Colloid region

b) Follicular cells

Question 12

Sodium-iodide symporter transports one Na+ ions and two I– ion into the cell.

a) True
b) False

Answer 12

b) False

Question 13

Sodium-iodide symporter transfers two sodium and one iodide from the plasma to the follicle cells. Iodide binds to thyroglobulin to form —–. T3 is formed from coupling of —-, whereas T4 is formed from coupling of —–.

a) T1
b) T2
c) T1 to T2
d) T2 to T2
e) T1 and T2

Answer 13

e) T1 and T2
c) T1 to T2
d) T2 to T2

Question 14

Oxidation of iodide ions, I-, to nascent iodine, I0, or I3- is promoted by —–

a) Hydroxylase
b) Ligase
c) Lipase
d) Peroxidase
e) Tyrosinase

Answer 14

d) Peroxidase

Question 15

Organification of thyroglobulin is the binding of oxidized —-to thyroglobulin to form T1 and T2.

a) Amine
b) Bromine
c) Chlorine
d) Iodine

Answer 15

d) Iodine

Question 16

• ——is the enzyme responsible for iodination of tyrosine to monoiodotyrosine (T1) and then to diiodotyrosine (T2).
  a) Hydrolase
  b) Ligase
  c) Peroxidase
  d) Thyroid peroxidase (TPO)
  e) Tyrosinase

Answer 16

d) Thyroid Peroxidse (TPO)

Question 17

In thyroid hormones synthesis, if T1 binds to T2 it forms —-, whereas if T2 binds to T1, it forms —–.

a) T1
b) T2
c) T3
d) rT3
e) T4

Answer 17

c) T3

d) rT3

Question 18

Does excess iodine intake is dangerous to your body? —, as it will ——.

a) Be excreted in urine
b) Cause hyperthyroidism
c) No
d) Yes

Answer 18

c) No

a) be excreted in urine

Question 19

Which of the following thyroid hormones has the highest biological activity?

a) T1
b) T3
c) T4
d) rT3
e) TSH receptor antibodies

Answer 19

b) T3

Question 20

Regulation of thyroid hormones is based on

a) Free T4 and free T3
b) Bound T4 and bound T3
c) Bound T4 and free T3
d) Bound T3 and free T4
e) Total T4 and T3

Answer 20

a) Free T4 and free T3

Question 21

T4 is converted to the active form T3 in the —–. Then T3 diffuses to the —–and binds to thyroid hormone receptor (THR), which binds to the thyroid response element (TRE) and initiate transcription and translation.

a) Colloid
b) Cytosol
c) Nucleus
d) Plasma

Answer 21

b) cytosol

c) nucelus

Question 22

The thyroid hormone T3 diffuses to the nucleus and binds to the —–, which binds to the ——and initiate transcription and translation.

a) Thyroid hormone receptor (THR)
b) Thyroid response element (TRE)
c) Thyroxine binding globulin (TBG)

Answer 22

a) Thyroid hormone receptor

b) Thyroid response element

Question 23

Thyroxine is converted to T3 by the aid of the enzyme:

a) Tyrosine peroxidase (TPO)
b) De-iodinase
c) Trypsin
d) Lipase

Answer 23

b) De-iodinase

Question 24

About 93 per cent of the thyroid hormones released from the thyroid gland is normally ——-, only 7 per cent is ————.

a) T1
b) T2
c) T1 and T2
d) T3
e) T4

Answer 24

e) T4

d) T3

Question 25

The active form of iodothyronine is-- a) T1 b) T2 c) T1 and T2 d) T3 e) T4

Answer 25

d) T3

Question 26

In the blood circulation, T3 and T4 bind to all the following EXCEPT a) Albumin b) Plasma proteins c) Thyroxin-binding Globulin (TBG) d) Thyroxin-binding prealbumin e) Mono- and di-iodothyronine

Answer 26

e) Mono and do-iodothyronine

Question 27

TSH is produced in the -----and it is downregulated by ----. a) Hypothalamus b) Anterior pituitary gland c) T3 d) T4 e) T3 and T4

Answer 27

b) Anterior Pituitary gland | e) T3 and T4

Question 28

When there is a deficiency of T3 and T4, the hypothalamus stimulates the production of -----, which stimulates the anterior pituitary gland to produce -----, which stimulates the thyroid gland to produce T3 and T4. Excess T3 and T4 are ----- for TRH and TSH. a) TRH b) TSH c) Negative feedback/inhibitors d) Positive feedback/stimulators

Answer 28

a) TRH b) TSH c) Negative feedback/inhibitors

Question 29

TRH is produced by the -----and it is downregulated by -----. a) Anterior pituitary gland b) Hypothalamus c) T1 and T2 d) T2 and T3 e) T3 and T4

Answer 29

b) Hypothalamus | e) T3 and T4

Question 30

With respect to thyroid gland: A disease in the thyroid gland is termed, ----disease, whereas, a disease in the hypothalamus/pituitary gland that affects the thyroid gland is termed, --- disease. a) Primary b) Secondary

Answer 30

a) Primary | b) Secondary

Question 31

The most common cause of hyperthyroidism is which of the following? a) Hashimoto's b) Toxic adenoma of c)the thyroid d) Grave's e) Iodine excess

Answer 31

d) Graves

Question 32

Which of the following autoantibodies is most commonly associated with Grave's disease? a) Anti TSH receptor antibodies b) Anti TPO antibodies c) Anti TBG antibodies d) Anti thyroglobuin antibodies

Answer 32

a) Anti TSH receptor

Question 33

In ----, anti TSH receptor antibodies (TSI) binds and stimulates the TSH receptor (on the thyroid gland). Accordingly, T3 and T4 are elevated, whereas TSH declines via negative feedback/ inhibition. a) Hashimoto's disease b) Toxic adenoma of the thyroid c) Grave's disease d) Iodine excess

Answer 33

c) Graves disease

Question 34

The most common cause of hypothyroidism is which of the following? a) Hashimoto's b) Toxic adenoma of the thyroid c) Grave's d) Iodine excess

Answer 34

a) Hashimotos

Question 35

Which of the following plasma values best represents the biochemical picture for a patient with Hashimoto's disease? a) Decreased TSH + elevated T4 b) Decreased TSH + decreased T4 c) Increased TSH + decreased T4 d) Normal TSH + elevated T4 e) Normal TSH + decreased T4

Answer 35

c) Increased TSH + decreased T4

Question 36

Which of the following autoantibodies is most commonly associated with Hashimoto’s disease? a) Anti TSH receptor antibodies b) Anti TPO antibodies c) Anti TBG antibodies d) Anti thyroglobuin antibodies

Answer 36

b) Anti TPO antibodies

Question 37

Among the front line tests for diagnosis in measurement of serum thyroid hormone levels are rT4 & TSH. a) True b) False

Answer 37

b) False

Question 38

What is the general structural characteristics of steroid hormones? a) 1 Six carbon ring + 3 five carbon rings b) 2 Six carbon rings + 2 five carbon rings c) 3 Six carbon rings + 1 five carbon ring d) 3 Six carbon rings + 3 five carbon rings e) 5 Six carbon rings + 1 five carbon ring

Answer 38

c) 3 Six carbon rings + 1 five carbon ring

Question 39

Which of the following is NOT among the steroid hormones? a) GlucocorticoidsMineralocorticoids b) Progestogens (progesterones) c) Sex Steroids d) Vitamin D e) T3 & T4

Answer 39

e) T3 & T4

Question 40

The starting compound for the synthesis of all steroid hormones is DHEAS. a) True b) False

Answer 40

b) False

Question 41

What is the starting compound for the synthesis of all steroid hormones? a) Cortisol b) Progesterone c) Estradiol d) Pregnenolone e) Testosterone

Answer 41

d) Pregnenolone

Question 42

The most abundant circulating steroid hormone in humans is Pregnenolone. a) True b) False

Answer 42

b) False

Question 43

What’s the most abundant circulating steroid hormone in humans? It is --------. Why it is important to human? It functions predominantly as a metabolic intermediate in the ------ of the androgen and estrogen sex steroids. a) Didehydroepiandrosterone (DHEAS) b) Biosynthesis c) Catabolism d) Pregnenolone

Answer 43

a) Didehydroepiandrosterone (DHEAS) | b) Biosynthesis

Question 44

In women, --------- as a sex hormone is more abundant than men, whereas, -------- is more abundant in men than women. On the other hand, ---------hormone’s concentration is doubled in men than women. a) Didehydroepiandrosterone (DHEAs) b) Progesterone c) Testestorone

Answer 44

b) Progesterone c) Testoserone a) Didehydroepiandrosterone (DHEAs)

Question 45

What dictates whether a tissue responds to steroid hormones or not? Some tissues have ----which can metabolize hormones, whereas others need ----- for hormonal response. a) Enzymes b) Proteins c) Steroid receptors

Answer 45

a) Enzymes | c) Steroid receptors

Question 46

What dictates whether a tissue responds to steroid hormones or not? - ----and enzyme profile, for example, ------ is required for aldosterone synthesis and they are only found in ------ (outer zone) of adrenal cortex. a) Aldosterone b) Hormone receptors c) Progesterone d) 18-hydroxylase e) zona glomerulosa cells

Answer 46

b) Hormone receptors d) 18-hydroxylase a) aldosterone e) zona glomerulosa cells

Question 47

What is the mineralocorticoid hormone that stimulates increased reabsorption of Na+ in exchange for excretion of K+ and H+? a) Aldosterone b) Androgens c) Estradiol d) Progesterone e) Pregnenolone

Answer 47

a) Aldosterone

Question 48

Conn’s disease is characterised by ------aldosterone, whereas Addison’s disease is characterised by ------aldosterone. a) High b) Low

Answer 48

a) High | b) Low

Question 49

What is the major stress hormone and it is in the group of glucocorticoid? a) Androgens b) Cortisol c) Estradiol d) Progesterone e) Pregnenolone

Answer 49

b) Cortisol

Question 50

People tend to -------weight when they are stressed and that due to increase of the hormone ---------? a) Gain b) Loose c) Androgens d) Cortisol e) Estradiol

Answer 50

a) Gain | d) Cortisol

Question 51

According to Circadian release of ------, it is recommended to do work in the early morning. a) Androgens b) Cortisol c) Estradiol d) Progesterone e) Pregnenolone

Answer 51

b) Cortisol

Question 52

Cortisol level is -----in the early morning and tends to be ------ at the time of sleep onset. Loss of cortisol circadian rhythm is associated with adrenal insufficiency and death. a) High b) Low

Answer 52

a) High | b) Low

Question 53

The adrenocortropic hormone (ACTH) stimulates the adrenal cortex to synthesize Corticotrophin Releasing Hormone(CRH). a) True b) False

Answer 53

b) False

Question 54

In case of injury, fear, or anxiety, the corticotrophin releasing hormone (CRH) is firstly synthesized in the hypothalamus. a) True b) False

Answer 54

a) True

Question 55

Negative feedback inhibition occurs when cortisol concentration is high and it affects -----. a) Adrenal cortex b) Adrenal cortex and Anterior pituitary gland c) Adrenal cortex and the hypothalamus d) Hypothalamus and Anterior pituitary gland e) Hypothalamus

Answer 55

d) Hypothalamus and anterior pituitary gland

Question 56

The hormone ----- is not stimulated by the pituitary hormones (trophic hormones). a) Aldosterone b) Cortisol c) Oestrogens d) Testosterone e) Progesterone

Answer 56

a) Aldosterone

Question 57

The hormones that stimulate secretion of other hormones are called: ----- hormones. a) Androgens b) Cortisol c) Estradiol d) Progesterone e) Trophic

Answer 57

e) trophic

Question 58

As examples of ----hormones, adrenocorticotrophic hormone (ACTH) stimulates ----, whereas ------stimulates testestorone/oestrogens, and ----- stimulates oestrogens. a) Androgens b) Cortisol c) follicle stimulating hormone (FSH) d) lutheinising hormone (LH) e) Trophic

Answer 58

b) cortisol d) Luteinising hormone c) follicle stimulating hormone

Question 59

Steroid hormones are water --------. Thus need a protein carrier to transport them in the plasma to the different cell membranes. a) soluble b) Insoluble

Answer 59

b) Insoluble

Question 60

Increase or decrease of gene transcription or mRNA synthesis is regulated by steroid hormones. a) True b) False

Answer 60

a) True

Question 61

Cortisol and aldosterone bind to their receptors ----the nucleus, whereas oestradiol and progesterone hormones bind to the receptors -----the nucleus. a) Inside b) Outside

Answer 61

b) outside | a) inside

Question 62

``` Steroid-receptor complexes aggregate into -----and are said to be -----. a) Homodimers b) Homotrimers c) Activated d) Deactivated ```

Answer 62

a) Homodimers | c) Activated

Question 63

The unoccupied hormone receptors are bound to heat shock protein to ----the binding of receptors to DNA and to -----the receptor is in the right conformation. a) Make sure b) Prevent

Answer 63

b) Prevent | a) Make sure

Question 64

The receptor homodimers hormone bind to the ----, which in turn bind to both the TATA binding protein and the ------to synthesise a new protein. a) Activators b) Co-activators c) DNA polymerase d) Kidney e) RNA polymerase

Answer 64

b) co-activators | e) RNA polymerase