Pineal gland, Biology

Assignment Help:

PINEAL GLAND (EPIPHYSIS CEREBRI) -

  • It develops from the ectoderm of the embryo.
  • The pineal gland is located between the cerebral hemispheres, where it protrudes from the roof of the third ventricle.
  • The pineal gland is a small rounded body which consists of pineal cells and supporting glial cells.

Hormone - Melatonin concentration in the blood appears to flow a diurnal (day-night) cycle as it arises, in the evening and through the night and drops to a low around noon. Because of this light mediated response, the pineal gland may act as a kind of "biological clock" which may produce circadian rhythms (variations following a 24 hour cycle).

  • Melatonin lightens skin colour in certain animals and regulates working of gonads (testes and ovaries).
  • Light falling on the retina of the eye decreases melatonin production, darkness stimulates melatonin synthesis.

                      Girls blind from birth attain puberty earlier than normal, apparently because there is no                             inhibitory effect of melatonin on ovarian function.

  • Serotonin, a neurotransmitter found in other locations in the brain, is also found in the pineal gland. Research evidence is accumulating to support the idea that the pineal gland may be involved in regulating cyclic phenomena in the body.
  • In man the pineal gland starts to calcify at about the time of puberty. Such calcium deposits are called the brain sand.

Related Discussions:- Pineal gland

Entropy, ENTROP Y - Transfer of energy takes place from high energy...

ENTROP Y - Transfer of energy takes place from high energy level to low energy level. Rudol f clausius gave this term. During it there is collision of particles, r

Phylum platyhelminhes, what are the classification of phylum platyhelminthe...

what are the classification of phylum platyhelminthes?

What are the typical fauna of the taigas, What are the typical vegetation a...

What are the typical vegetation and the typical fauna of the taigas? Taiga, or the boreal forest, is characterized by coniferous trees, pine forests. There are also mosses, lic

What are three main problems with having only two kingdoms, What are three ...

What are three main problems with having only two kingdoms There are three main problems with having only two kingdoms. The first problem concerns the unicellular flagellates

Explain pollen grains, Transfer of pollen grains from the anther to the sti...

Transfer of pollen grains from the anther to the stigma of another flower of the similar plant is known as? Geitonogamy

What herniation of a disc means, A woman was injured several years ago in a...

A woman was injured several years ago in a car accident and she was diagnosed with a herniated disc. Can you please explain using the correct anatomical terminology what herniation

Explain terms of osmosis, A red blood cell has an internal salt concentrati...

A red blood cell has an internal salt concentration of 150mM. The cell is placed in a beaker of 500mM salt. (a) Assuming that the cell membrane is permeable to water but not to

Brain neurosecretory cells and their hormones, Brain Neurosecretory Cells a...

Brain Neurosecretory Cells and their Hormones Kopec was the very first to suggest the role of hormones in controlling metamorphosis. On the base of his experiments on the lar

Surgical treatment options, Cardiomyoplasty This is a procedure wherei...

Cardiomyoplasty This is a procedure wherein the latissimus dorsi muscle is wrapped around the heart and stimulated to contract synchronously with it. It has been largely given

Membrane oxygenators-type of oxygenators , Membrane Oxygenators: They are...

Membrane Oxygenators: They are more physiological and are similar to natural lungs. There is separation of blood and gas by membrane across which gas exchange takes place. There

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd