Tag: endocrine system and chemical co-ordination

Questions Related to endocrine system and chemical co-ordination

Melatonin is secreted by.

  1. Pineal body

  2. Skin

  3. Pituitary gland

  4. Thyroid


Correct Option: A

The pineal body is considered as

  1. An endocrine gland

  2. An organ concerned with voluntary actions

  3. An organ concerned with vision

  4. A vestige of third eye and endocrine gland


Correct Option: D
Explanation:
The pineal body is made up of the secretory cells called the pineolocytes. It is attached to the roof of the epithalamus in the diencephalon of the forebrain. During the embryonic development, it is found attached to the brow spot between the eyes of the developing embryo. In some reptiles, the pineal gland is present in the form of the parietal eye or the pineal eye which is photosensitive and is involved in regulating the diurnal cycle. In mammals, it does not form the photosensitive structure but it is involved in the secretion of the hormone called the melatonin which regulates the sleep-wake cycle. It is degraded during the bright light and accumulates in dim light.
Hence, the correct answer is 'A vestige of third eye and endocrine gland'

Identify the hormone with its correct matching of source and function.

  1. Oxytocin - posterior pituitary, growth and maintenance of mammary glands

  2. Melatonin- Pineal gland, regulates the normal rhythm of sleepwake cycle

  3. Progesterone- Corpus luteum, stimulation of growth and activities of female secondary sex organs

  4. Atrial natriuretic factor - ventricular wall, increases the blood pressure


Correct Option: B
Explanation:

Melatonin, is a hormone that is produced by the pineal gland and regulates sleep and wakefulness. Blood levels of the pineal hormone melatonin are high at night and low during the day. There, a special center called the suprachiasmatic nucleus (SCN) initiates signals to other parts of the brain that control hormones, body temperature and other functions that play a role in making us feel sleepy or wide awake. During the day the pineal is inactive. When the sun goes down and darkness occurs, the pineal is "turned on" by the SCN and begins to actively produce melatonin, which is released into the blood. As a result, melatonin levels in the blood rise sharply and you begin to feel less alert. Sleep becomes more inviting. 

So, the correct answer is option B.

Gradual atrophy degeneration with ageing its shown by

  1. pineal gland

  2. thymosin

  3. adreal cortex

  4. Both a and b


Correct Option: A

Which of the following is responsible for sleep wake cycle movement?

  1. Dopamione

  2. Melatonin

  3. Serotonin

  4. Adrenaline


Correct Option: B
Explanation:
Option B is correct here.

The circadian rhythm is set by the suprachiasmatic nucleus of the hypothalamus, which regulates the sleep-wake cycle.
The suprachiasmatic nucleus projects to the pineal gland to release melatonin, which promotes sleep. 
At the time of morning melatonin secretion through pineal gland get low and get stop slowly because of that person get wake up.

Melatonin is modified

  1. Amino acid

  2. Peptide

  3. Steroid

  4. Protein


Correct Option: A
Explanation:
  • Melatonin is a hormone that regulates sleep-wake cycles. It is primarily released by the pineal gland. 
  • As a supplement, it is often used for the short-term treatment of trouble sleeping such as from jet lag or shift work. 
  • Melatonin is a hormone which is a protein made up of amino acids. 
  • Hence, Melatonin is a modified Amino acid. 
  • So, the correct answer is 'amino acid'.

Which of the following gland in our body controls the biological clock in the human body?

  1. Pitutary gland

  2. Thyroid gland

  3. Pineal gland

  4. Parathyroid gland


Correct Option: C
Explanation:

  • The pineal gland is an endocrine gland located on the dorsal side of the forebrain. Pineal secretes a hormone called melatonin.
  • Melatonin plays a very important role in the regulation of a 24-hour (diurnal) rhythm of our body. For example, it helps in maintaining the normal rhythms of the sleep-wake cycle, body temperature. In addition, melatonin also influences metabolism, pigmentation, the menstrual cycle as well as our defense capability. Hence the gland in our body that controls biological clock is a Pineal gland.

So, the correct answer is 'Pineal gland'.

Which of these hormones may have a primary role in many circadian rhythms?

  1. Insulin

  2. Estradiol

  3. Melatonin

  4. Epinephrine


Correct Option: C
Explanation:

The circadian rhythm or 24 hours diurnal rhythm of our body is maintained by Melatonin hormone secreted from the Pineal gland which is located on the dorsal side of forebrain. In addition, the melatonin hormone even assist in metabolism, pigmentation and even maintaining our defence capabilities.

So, the correct answer is 'Melatonin'.

Hyper secreation of Parathyroid hormone result in ___________________.

  1. Stronger bones due to increased incorporation of calciuim in them.

  2. Deposition of calcium in various skeletal structure.

  3. No effect on the constitution of bones

  4. Weaker bones due to increased removal of calcium from them


Correct Option: B
Explanation:

 A parathyroid gland tumor can prompt hypersecretion of PTH. This can raise blood calcium levels so excessively that calcium deposits begin to accumulate throughout the body, including in the kidney tubules. When calcium levels in your blood fall too low, your parathyroid glands secrete enough PTH to restore the balance but sometimes these glands produce an excess amount of hormone, leading to abnormally high levels of calcium (hypercalcemia) and low levels of phosphorus in your blood.

So, the correct answer is 'Deposition of calcium in various skeletal structures.'

Philips Collip discovered which of the following hormones?

  1. Parathyroid hormone

  2. Thyroxine

  3. ADH

  4. Oxytocin


Correct Option: A
Explanation:

Bovine parathormone is a large polypeptide having 84 amino-acids. It was discovered and purified by Philips Collip in 1925.