Tag: zoology

Questions Related to zoology

Which of the following is a mineralocorticoid?

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Testosterone

  2. Progesterone

  3. Adrenaline

  4. Aldosterone

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Correct Option: D
Explanation:

Aldosterone is a major mineralocorticoid, secreted by adrenal cortex. It regulates mineral metabolism and controls the sodium and potassium ratio in the extracellular and intracellular fluid. Therefore, it is called salt-retaining hormone.

Reabsorption of $Na^+$ is controlled by which one of the following hormones?

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Aldosterone

  2. Estrogen

  3. Glucocorticoids

  4. Testosterone

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Correct Option: A
Explanation:

Aldosterone(secreted by adrenal medulla) acts mainly on the renal tubules and stimulates the reabsorption of $Na^+$ and water and excretion of $K^+$ and phosphate ions.

Glucocorticoid hormones are secreted by the:

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. adrenal medulla

  2. islets of Langerhans

  3. parafollicular cells

  4. adrenal cortex

Show answer
Correct Option: D
Explanation:

(a) The adrenal medulla secretes two hormones called adrenaline and noradrenaline.

(b) The pancreas is a composite glans which acts as both exocrine and endocrine gland. The endocrine pancreas consists of Islets of Langerhans. 
(c) Parafollicular cells are neuroendocrine cells in the thyroid which primary function is to secrete calcitonin.
(d) The adrenal cortex secretes many hormones called as corticoids. The corticoids which are involved in carbohydrate metabolism are called glucocorticoids. 
So the correct option is adrenal cortex.

Which of the following hormones is not proteinaceous is nature?

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. TSH

  2. Aldosterone

  3. LH

  4. FSH

Show answer
Correct Option: B
Explanation:

Aldosterone is a steroid hormone and has three cyclohexyl rings and one cyclopentyl ring joined into a single structure. TSH, FSH and LH are peptide hormones and have long amino acid chains. Thus, the correct answer is option B. 

Zona fasciculata secretes

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Aldosterone

  2. Cortisol

  3. Thyroxine

  4. Adrenaline

Show answer
Correct Option: B
Explanation:

Adrenal gland just lies above the kidney. It is divided into two regions outer cortex and inner medulla. Cortex region secret the steroid hormone. Inner medulla region is divided into three regions zona glomerulosa, zona fasiculata and zona reticularis. Each zone is responsible for secreting specific hormone.

 Name of the hormone Organ 
 Aldosterone  Secreted by zona glomerulosa (adrenal cortex)
 Cortisol Secreted by zona fasiculata (adrenal cortex)
 Thyroxine  Secreted by the thyroid gland
 Adrenaline  Secreted by the adrenal medulla

So, the correct answer is ' Cortisol '

Which of the following induces goose flesh?

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Adrenal Cortex

  2. Adrenal medulla

  3. Pituitary

  4. Thyroxine

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Correct Option: B

The sympathetic nervous system is responsible for the fight-or-flight response in humans. One neurotransmitter involved in this response is epinephrine. This excitatory molecule increases blood glucose by signaling the conversion of pyruvate into glucose.
Identify a potential target receptor cell of epinephrine in the fight-or-flight response.

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Liver cells.

  2. Cells in the pancreas that produce insulin.

  3. There is a specific target cell since epinephrine will work on all cells in the body and only cause a response in cells with intracellular receptors.

  4. Lung cells.

Show answer
Correct Option: A
Explanation:

Liver cells contain glucose stored in the form of glycogen (glucagon enzyme), which is converted to glucose and released in the blood stream to provide muscle cells and brain with the required energy to respond to the stimulus instantaneously during a fight-or -flight response.

So, epinephrine should have receptors sites on liver cells or adipose cells which store energy molecules
So, the correct answer is 'Liver cells'

Aldosterone hormone is a 

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Steroid

  2. Protein

  3. Amino acid derivative

  4. None of the above

Show answer
Correct Option: A
Explanation:

The hormone like cortisol and aldosterone are secreted from the adrenal cortex. It is an example of steroid hormone. It regulates the salt and water balance in body.

Which one of the following hormones also produces anti-inflammatory reactions in man and suppresses the immune response in addition to its primary functions?

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Thyrocalcitonin

  2. Cortisol

  3. Erythropoietin

  4. Thymosin

Show answer
Correct Option: B
Explanation:

Cortisol has a powerful anti-inflammatory action, even when secreted at normal levels. It acts quickly to remove and prevent redness and swelling of nearly all tissues. Cortisol also reduces the rate at which lymphocytes multiply and accelerates their programmed cell death to further protect the body from this overreaction. In fact, when cortisol is elevated during the alarm reaction stage, there is almost a complete disappearance of lymphocytes from the blood. That is why the immune system is suppressed when the body is under stress or taking corticosteroids. 

So, the correct answer is B.

Significant cause of 'adrenal virilism ' is :

zoology the endocrine system adrenal gland thymus and adrenal gland adrenal glands

  1. Hyposecretion of adreno-cortical androgens

  2. Hypersecretion of adreno-medullary androgens

  3. Hyposecretion of adreno-medullary androgens

  4. Hypersecretion of adreno-cortical androgens

Show answer
Correct Option: D
Explanation:

Adrenal virilism is a syndrome in which there is excess production of adrenal androgens. It is also called as adrenogenital syndrome. In this, there is hypersecretion of adrenocortical androgens. This is caused due to tumor of adrenal gland, called as adrenocortical carcinoma. It may also results from hyperplasia.

Thus, the correct answer is option D.