Tag: pineal gland and thymus

Questions Related to pineal gland and thymus

Melatonin is produced from 

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Pineal gland

  2. Adrenal gland

  3. Parathyroid gland

  4. Ovary

Show answer
Correct Option: A
Explanation:
A. Pineal gland produces melatonin which regulate 24 hour (diurnal) rhythm of the body.
B. Adrenal gland produces adrenaline and noradrenaline by adrenal medulla and corticoids by adrenal cortex.
C. Parathyroid gland produces parathyroid hormone (PTH).
D. Ovary produces estrogen and progesterone.
So, the correct answer is 'Pineal gland'.

The pineal gland secretes a hormone progesterone which helps to regulate sleep pattern. Thyroid glands release hormone which regulate the level of calcium in the blood with the help of calcitonin which is produced in the parathyroid glands. Select the correct option regarding the given paragraph.
i) Positions of pineal and parathyroid should be interchanged
ii) Progesterone must be replaced by melatonin
iii) Parathyroid should not be replaced as it is correctly mentioned.
iv) Positions of progesterone and calcitonin should be interchanged
v) Positions of thyroid and parathyroid should be interchanged 

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. ii and v only

  2. i, ii and v only

  3. i and iii only

  4. ii and iv only

Show answer
Correct Option: A
Explanation:

The correct statement is- 'The pineal gland secretes a hormone melatonin which helps to regulate sleep pattern. Parathyroid Gland release hormone which regulates the level of calcium in the blood with the help of calcitonin which is produced in the thyroid gland.'

So the correct option is 'ii and v only'.

The function of pineal body is to.

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Lighten the skin colour

  2. Control sexual behaviour

  3. Regulate the period of puberty

  4. All of these

Show answer
Correct Option: D
Explanation:

Pineal body is a very small, reddish-grey, vascular, conical, solid body located in the brain. It secretes a hormone named melatonin. Melatonin concentrates pigment granules in the melanocytes, making the skin colour lighter in certain animals. It also regulates the functioning of gonads, thus, controls, sexual behaviour and regulates the period of puberty.

A hormone responsible for normal sleep-wake cycle is?

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Epinephrine

  2. Gastrin

  3. Melatonin

  4. Insulin

Show answer
Correct Option: C
Explanation:

Melatonin is a hormone secreted by pineal gland. Immediately above the optic chiasma(in the brain) in a nucleus, are present melatonin receptors that react to this hormone and synchronise the nucleus to the $24$hrs day/night rhythm, thus informing the brain when it is day and when it is night.

Melatonin is secreted by.

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Pineal body

  2. Skin

  3. Pituitary gland

  4. Thyroid

Show answer
Correct Option: A

The pineal body is considered as

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  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

Show answer
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.

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  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

Show answer
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

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. pineal gland

  2. thymosin

  3. adreal cortex

  4. Both a and b

Show answer
Correct Option: A

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

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Dopamione

  2. Melatonin

  3. Serotonin

  4. Adrenaline

Show answer
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

zoology endocrine system and chemical co-ordination pineal gland pituitary gland and pineal gland pineal gland and thymus

  1. Amino acid

  2. Peptide

  3. Steroid

  4. Protein

Show answer
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'.