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

What are the physical properties of tear film, What are the physical proper...

What are the physical properties of Tear Film? Physical Properties of Tear Film: The tear film is a three-layered structure as given below: 1) Outermost Layer: Lipid Layer

Define lamivudine, Lamivudine This oral antiretroviral nucleoside analo...

Lamivudine This oral antiretroviral nucleoside analog used to treat HIV is also FDA-approved for treatment of chronic HBV infection. A trial in Asian patients with chronic HBV

What is self-catalytic rnas, Q. What is self-catalytic RNAs? Ribozymes...

Q. What is self-catalytic RNAs? Ribozymes - Term 'ribozyme' was initially suggested by Thomas R. Cech, Nobel Prize winning biochemist, who discovered this class of RNA molecul

Explain pyruvate kinase, Pyruvate kinase catalyzes the third irreversible m...

Pyruvate kinase catalyzes the third irreversible move in glycolysis.  It is activated by fructose 1, 6-bisphosphate.  The ATP and amino acid alanine allosterically inhibit the enzy

Polychaetes - feeding and digestion in annelids, Polychaetes - Feeding and ...

Polychaetes - Feeding and Digestion in Annelids Polychaetes involve both free moving (errant) and sedentary species. The free moving species are usually macrophagous and the s

Define nutritional management of eating disorders, Define Nutritional Manag...

Define Nutritional Management of Eating Disorders? In the last unit, we focused on weight management. It is important to understand that the problems associated with too much d

Disadvantages of m - mode echocardiography, Various structures are seen in...

Various structures are seen in two-dimensional planes; hence mental conceptualization is still required because the heart is three-dimensional. Now, newer technology has evolved

Modern theory in biology, Modern Theory Naturalistic theory: Accordin...

Modern Theory Naturalistic theory: According to this theory Life originated upon our earth spontaneously from nonliving matter. But there are two significant points in this r

Define tests to measure muscular strength and endurance, Define Tests to Me...

Define Tests to Measure Muscular Strength and Endurance? It is important to first understand the difference between muscular strength and endurance. To know the muscular streng

Explain cell membrane and plasma membrane, Explain cell membrane? The...

Explain cell membrane? The Cell Membrane :  The cell membrane, or plasma membrane, separates the cell from neighboring cells or from the external environment. Both prokaryot

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