Tag: endocrine system and chemical co-ordination

Questions Related to endocrine system and chemical co-ordination

A person is having problems with calcium and phosphorus metabolism in his body. Which one of the following glands may not be functioning properly?

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Pancreas

  2. Parotid

  3. Parathyroid

  4. Thyroid

Show answer
Correct Option: C
Explanation:
 There are 4 types of parathyroid glands, two inferior and two superior, located on the posterior surface of the thyroid gland. the produce and secrete parathyroid hormone (PTH). It is also called as parathormone. PTH controls the calcium concentration in the blood. The main function is to regulate calcium absorption from the intestines and excretion of calcium by kidneys. It also helps release calcium from the bones into the bloodstream when there is dropping of calcium level in the body. The improper functioning of parathyroid may lead to problems in calcium metabolism. 
So, the correct option is 'Parathyroid'.

Osteoporosis is caused by

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Fe$^{2+}$ defeciency

  2. Na$^+$ deficiency

  3. Parathormone hyposecretion

  4. Parathormone hypersecretion

Show answer
Correct Option: D
Explanation:
Osteoporosis is a condition in which bone density decreases and bones become weak and brittle. It occurs due to hypersecretion of parathormone. Parathormone is secreted from the parathyroid hormone and increases blood calcium level by increasing the reabsorption of calcium from the bones. Over secretion of parathormone causes more calcium dissolution from the bones leading to decreased bone density.
So, the correct answer is 'Parathormone hypersecretion'.

Hormone regulating calcium and phosphorus metabolism in the body is secreted by 

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Thyroid

  2. Parathyroid

  3. Thymus

  4. Pancreas

Show answer
Correct Option: B
Explanation:
A. Thyroid gland is situated between the trachea and larynx in the neck and secretes thyroxine hormone which increases oxygen consumption by metabolically active tissues.
B. Parathyroid gland is present in the form of four small pouches which are embedded in the posterior surface of lobes of thyroid gland. This gland secretes parathormone which increases calcium reabsorption from the bones and causes mobilisation of calcium in the blood. This hormone also regulates phosphate excretion through urine.
C. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.
D. Pancreas is a heterocrine gland as it acts both as endocrine and exocrine gland. It secretes insulin hormone into blood and act as endocrine gland and when it secretes digestive enzymes and juice through pancreatic duct, it acts as exocrine gland.
Hence, hormone regulating calcium and phosphorus metabolism in the body.
So, the correct answer is 'Parathyroid'.

Parathormone is secreted when there is 

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Increased Ca$^{2+}$ level in blood

  2. Decreased blood Ca$^{2+}$ level

  3. Increased blood sugar level

  4. Decreased blood sugar level

Show answer
Correct Option: B
Explanation:

The parathyroid glands secrete a peptide hormone called parathyroid hormone or parathormone (PTH). The release of parathromone is regulated by the circulating levels of calcium ($Ca^{2+}$) ions in the blood. PTH plays an important role in calcium balance of the body. It maintains the calcium balance between the blood and other tissues. When the calcium level in the blood decreases, parathyroid hormone is released in order to increase the calcium level in the blood. PTH acts on bones and other skeletal structure and mobilizes the calcium ($Ca^{2+}$) from the bones into the blood. This is called bone resorption/dissolution/demineralization. The parathromone also increases the reabsorption of calcium by the renal tubules and absorption of calcium from the digested food. Hence, PTH (parathormone) is a hypercalcemic hormone that increases the blood calcium levels.

Choose the correct answer from the alternatives given.
Parathyroid hormone (PTH) and calcitonin (CT) control the levels of which of the following ions in blood?

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Calcium

  2. Sodium

  3. Potassium

  4. Chloride

Show answer
Correct Option: A
Explanation:

The thyroid gland secretes a protein hormone called thyrocalcitonin (TCT) which regulates the blood calcium levels. Parathyroid hormone (PTH) increases the calcium levels in the blood. It also stimulates reabsorption of calcium by the renal tubules and increases calcium absorption from the digested food.

So the correct answer is calcium.

Low Ca$^{2+}$ in body fluid may be the reason for 

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Anaemia

  2. Angina pectoris

  3. Gout

  4. Tetany

Show answer
Correct Option: D
Explanation:
Low calcium levels in body cause hypocalcaemia. This may cause tetany, a disorder that occurs due to deficiency of parathormone. Parathormone is secreted from the parathyroid gland and increases blood calcium level by increasing the reabsorption of calcium from the bones. When parathormone levels are low, calcium level also gets decreased and this cause muscular spasms, a symptom of tetany. The muscles contract involuntarily and this causes painful cramps.
So, the correct answer is 'Tetany'.

Which one of the following pairs correctly matches a hormone with a disease resulting from its deficiency : -

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Relaxin Gigantism

  2. Prolactin Cretinsim

  3. Parathyroid hormone Tetany

  4. Insulin Diabetes insipidus

Show answer
Correct Option: C
Explanation:
  • Gigantism is a rare condition of accelerated growth and increased height as a result of too much growth hormone secretion during childhood or adolescence. It is almost always the result of a growth hormone-secreting pituitary tumour.
  •  Congenital hypothyroidism (under activity of the thyroid gland at birth), which results in growth retardation, developmental delay, and other abnormal features. Cretinism can be due to a deficiency of iodine in the mother's diet during pregnancy.
  • Hypoparathyroidism is decreased function of the parathyroid glands with underproduction of parathyroid hormone. This can lead to low levels of calcium in the blood, often causing cramping and twitching of muscles or tetany (involuntary muscle contraction) and several other symptoms.
  • Diabetes mellitus occurs due to insulin resistance or insulin deficiency and subsequent high blood glucose levels. Diabetes Insipidus, on the other hand, develops as a result of the stilted production of a hormone in the brain, which is released to stop the kidneys producing so much urine in order to retain water.

So, the correct answer is 'Parathyroid hormone Tetany'.

Increase in bleeding time and delay in blood coagulation occur due to deficiency of 

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Adrenaline

  2. Noradrenaline

  3. Parathormone

  4. Thyroxine

Show answer
Correct Option: C
Explanation:
Parathormone is secreted from the parathyroid gland and increases blood calcium level by increasing the reabsorption of calcium from the bones. A deficiency of parathormone causes deficiency of calcium in blood. Calcium plays an important role in blood coagulation as aggregation of platelets and formation of fibrin fibres at the wound site require calcium.
So, the correct answer is 'Parathormone'.

The condition of having excess levels of potassium in blood is called _______.

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Hypercholesterolemia

  2. Hyperkalemia

  3. Osteomalacia

  4. Hypernatremia

Show answer
Correct Option: B
Explanation:
A. Hypercholesterolemia is a condition of high cholesterol in blood.
B. Hyperkalemia is a condition of high potassium levels in blood.
C. Osteomalacia is a condition in which bones get softened due to deficiency of calcium or vitamin D.
D. Hypernatremia is a condition of high sodium concentration in blood.
So, the correct answer is 'Hyperkalemia'.

Hypercalcemic hormone is 

zoology endocrine system and chemical co-ordination parathyroid gland thyroid and parathyroid gland thyroid, parathyroid and thymus gland

  1. Thyroxine

  2. Tri-iodo-thyronine

  3. Parathormone

  4. Thyrocalcitonin

Show answer
Correct Option: C
Explanation:

Parathormone is a hypercalcemic hormone that increases the blood calcium levels. The parathyroid glands secrete a peptide hormone called parathyroid hormone or parathormone (PTH). The release of parathromone is regulated by the circulating levels of calcium ($Ca^{2+}$) ions in the blood. PTH plays an important role in calcium balance of the body. It maintains the calcium balance between the blood and other tissues. When the calcium level in the blood decreases, parathyroid hormone is released in order to increase the calcium level in the blood. PTH acts on bones and other skeletal structure and mobilizes the calcium ($Ca^{2+}$) from the bones into the blood. This is called bone resorption/dissolution/demineralization. The parathromone also increases the reabsorption of calcium by the renal tubules and absorption of calcium from the digested food.