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 is the vector of malaria, Q. What is the vector of malaria? How differ...

Q. What is the vector of malaria? How different is its behavior from the behavior of the vector of dengue fever? The vector of malaria is the mosquito of the genus Anopheles, a

What is ecotourism and how it preserve biodiversity, What is ecotourism, an...

What is ecotourism, and how can it be used to preserve biodiversity? Ecotourism is tourism involving people who want to see intact ecosystems and their unique organ- isms. Inco

Define photoorganoheterotrophs and chemoorganoheterotrophs, Photoorganohete...

Photoorganoheterotrophs and Chemoorganoheterotrophs - Nutritional Types (1) Photoorganoheterotrophs - These microorganisms use light as a source of energy and organic compound

Types of glials cells and their functions, Types of Glials Cells and their ...

Types of Glials Cells and their Functions In the nervous tissue, besides the nerve cells there is one other cell type -the neuroglia which is present in large numbers and occu

Explain iron uptake by cells, Explain Iron Uptake by Cells? Iron partic...

Explain Iron Uptake by Cells? Iron participates in a large number of biochemical reactions. However, for iron to perform any function, it first needs to be taken up by the cell

Respiratory system in fishes, The fishes belong to class Pisces under verte...

The fishes belong to class Pisces under vertebrates. 2. In fishes, the respiratory system consists of mouth, pharynx, internal branchial apertures, branchial pouches and external b

Leukemia and explain why each finding occurs in this disease, Patient is a ...

Patient is a 7-year-old girl who was brought to her physician by her mother with complaints of general fatigue, anorexia, and unexplained bruises and "rash" for the past 2 weeks. C

How implants increases the magnitude significantly, How implants increases ...

How implants increases the magnitude significantly The patient should be medically fit to undergo the surgery. Placement of one or two implants is equivalent to relatively mino

When aerobic cells carry out fermentation, Under which conditions do aerobi...

Under which conditions do aerobic cells carry out fermentation? Some cells that as a rule get energy from aerobic cellular respiration can carry out fermentation when oxygen is

Explain sound production - ethological approach in taxonomy, Explain Sound ...

Explain Sound production - Ethological Approach in Taxonomy The most used, ethological feature in identification is the sound produced by various species of animals. This is

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