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

Define the general mortality and morbidity risk, Define the General Mortali...

Define the General Mortality and Morbidity Risk? Obesity increases the risk of morbidity and mortality. The obese are more prone to developing morbidities or other chronic dise

Zoology, general characteristics of phylum chordata

general characteristics of phylum chordata

Why is it not correct to assert that the dna, Q. Why is it not correct to a...

Q. Why is it not correct to assert that the DNA self- replicates? The DNA is not completely self-sufficient in its duplication process because the replication does not occur wi

What is cartilage explain briefly, What is Cartilage explain briefly? S...

What is Cartilage explain briefly? Some bones, such as the bones in the skull, develop directly from membranous connective tissue, but in human fetal development, most of the s

Egg - synergids, Egg - Synergids The three cells of the egg apparatus ...

Egg - Synergids The three cells of the egg apparatus are arranged in triangular fashion with the egg sharing a common wall with the two synergids and the central cell. In the

Explain the basic working of cellular functioning, Q Which is the biologica...

Q Which is the biological molecule that holds the genetic information that is transmitted hereditarily and controls the cellular functioning? The hereditary molecule that contr

What is the function of the flagellum of the sperm cell, Q. What is the fun...

Q. What is the function of the flagellum of the sperm cell? How is it formed? The flagellum of the sperm cell is made by the centrioles that migrate to the region posterior to

Difference between distant object and near object, Difference between Dista...

Difference between Distant object and Near object - Distan t object Near object   1. Parallel light reaches to eye.   2. Ci

What are polysaccharides, What are Polysaccharides? Polymers of simple ...

What are Polysaccharides? Polymers of simple sugars are known as Polysaccharides. Several polysaccharides, unlike sugars, are insoluble in water. Dietary fibre includes polysac

Rejection reaction, Rejection Reaction For rejection reaction the phys...

Rejection Reaction For rejection reaction the physiological and biochemical processes are set in the pistil by the recognition reaction specific to the type of pollen that lan

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