Question

1.The thyroid gland:

shrinks when a person has goiter, which is caused by an iodide deficiency.

produces thyrotropin-releasing hormone.

sequesters iodide from the diet, and synthesizes thyroxine and T3.

produces thyroid-stimulating hormone.

stores thyroxine for up to months in the thyrotropes.

2. Increasing the concentrations of which of the following would cause the largest increase in calcium concentrations in the extracellular fluid?

activating osteoblasts

increasing the plasma concentrations of parathyroid hormone and calcitonin

activating the chondrocytes

increasing the plasma concentrations of parathyroid hormone and calcitriol

increasing the plasma concentrations of calcitonin and calcitriol

3. Iodine is required for the synthesis of:

epinephrine.

cortisol.

T3 and T4.

adrenocorticotropic hormone (ACTH).

testosterone.

4. Which disease of the thyroid gland is correctly matched with its outcome?

hyperthyroidism (Graves’ disease): fast metabolism, cold intolerance, water retention and lethargy.

cretinism: mental retardation and excessively long limbs.

none of the answers are correct.

hypothyroidism (Hashimoto’s disease): fast metabolism, heat intolerance, water retention and lethargy.

goiter: atrophy of the thyroid

5. Which of the following are all synthesized from cholesterol?

cortisol, aldosterone, estrogen, testosterone

epinephrine, norepinephrine, thyroxine

glutamate, GABA, acetylcholine

thyroxine, T3, T4

thyroid-stimulating hormone (TSH), luteinizing hormone (LH), follicle-stimulating hormone (FSH)

6. What would be the effect of blocking the release of cortisol? Concentrations refer to general concentrations in the plasma of the blood.

Corticotropin-releasing hormone is CRH. Adrenocorticotropic hormone is corticotropin or ACTH. Concentrations refer to the concentrations in the blood (serum concentrations) relative to normal.

The person would have symptoms that would be the same as a patient with a hyperactive hypothalamus.

concentration of CRH would be high, concentration of ACTH would be high

concentration of CRH would be high, concentration of ACTH would be low

The person would have symptoms that would be the same as a patient with a hyperactive pituitary gland.

concentration of CRH would be low, concentration of ACTH would be low

7. The ultimate effect of growth hormone is to:

all the answers are correct.

increase bone length by actions on the osteoclasts AND decrease adipose (fat) content by increasing catabolism

increase muscle mass by enhancing catabolism.

decrease adipose (fat) content by increasing catabolism.

increase bone length by actions on the osteoclasts.

8. If someone has a goiter, you would predict that:

they had normal blood concentrations of T3 and T4.

they had low blood concentrations of T3 and T4.

you would need more information to make a prediction.

they had high blood concentrations of T3 and T4.

they had high blood concentrations of T3 and low concentrations of T4.

9. Which of the following best describes the formation of bone?

Chondrocytes calcify the circumference of the bone to increase the radius.

Osteoblasts seal the bone, so that there is no blood flows into the interior, which strengthens the bone.

The epiphyseal plates secrete parathyroid hormone to inhibit bone growth.

none of the answers are correct.

Osteoclasts calcify the cartilage secreted by chondrocytes.

10. Which of the following is required for the synthesis of the other four?

progesterone

cortisol

aldosterone

pregnenolone

estradiol

Answer 1

1. The thyroid gland sequesters iodine from the diet, and synthesises thyroxine and T3.

The other options are wrong because:

The gland doesn’t shrink instead it enlarges in goitre.

Thyrotropin releasing hormone is released by hypothalamus.

Thyroid stimulating hormone is release by pituitary gland .

Thyrotropes doesn’t store thyroxine. They secrets thyroid stimulation hormone(TSH).

2. Increase in the plasma concentration of parathyroid hormone and Calcitriol helps increase the calcium concentration in the extra cellular fluid.

The other options are wrong because:

Osteoblasts draw calcium from blood for bone formation reducing its concentration in extra cellular fluid. Calcitonin decreases blood calcium and deposits in the bone.

Parathormone causes resorption of bone and increase blood calcium. Calcitriol increase calcium absorption from the gut and kidneys into the blood causing an increase in the blood calcium.

3. Iodine is required for the synthesis of T3 & T4. Di-iodothyronine combines with thyronine forms T3.

Two di-iodothyronine molecules combine to form T4.

4. None of the answers are correct.

Hyperthyroidism doesn’t cause water retention and lethargy.

Cretinism is associated with short limbs.

Hypothyroidism in Hashimoto’s disease is associated with slow metabolism not fast metabolism.

Goitre is not associated with atrophy of thyroid gland. It causes engagement of gland.

5. Cortisol, aldosterone, oestrogen and testosterone are all steroid hormones that are synthesised from cholesterol.

6. Blocking of the release of cortisol results in high concentrations of both CRH and ACTH. The concentration of these hormones are increased in order to stimulate the adrenal gland and increase the release of cortisol.

7.The ultimate effect of growth hormone is to decrease adipose (fat) content by increasing catabolism.

Bone length increase is achieved by osteoblasts not osteoclasts.

Muscle mass is increased by anabolism, not by catabolism.

8. You wound need more information to make a prediction cause goitre can be associated with either increase or decrease in the T3 and T4 levels. This makes it impossible to make a prediction on the presence of goitre alone.

9.None of the given options are correct.

Chondrocytes doesn’t help in the metabolism of bone at all. They produce the matrix for cartilage.

Osteoblasts help in bone formation but not in sealing the bone. The bone marrow is rich in blood supply. Osteoclasts help in bone resorption but not in calcifying cartilage.

The epiphyseal plates help bone growth promotion not in the growth inhibition.

10. Pregnenolone.

PREGNENOLONE gives rise to PROGESTERONE which helps form CORTISOL and ALDOSTERONE.

It also gives rise to DHEA which helps in the formation of TESTOSTERONE which give rise to ESTRADIOL.

This is a brief explanation for the questions given. Hope this Helps you. Please feel free to give your feedback and if you need further detailed explanation. Thank you and have a great day.