Pineal gland, Biology

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.
Posted Date: 10/2/2012 7:08:56 AM | Location : United States







Related Discussions:- Pineal gland, Assignment Help, Ask Question on Pineal gland, Get Answer, Expert's Help, Pineal gland Discussions

Write discussion on Pineal gland
Your posts are moderated
Related Questions
Conduction in Myelinated Axons The myelin sheath provides insulation for the axon preventing movements of Na + and K + through the membrane. Therefore, if this myelin sheath

Adverse Effects of Acyclovir By any route of administration, acyclovir is generally well tolerated. Gastrointestinal (GI) disturbances and headache can occur. Given IV, the dr

Define Management of Canal Blockage Canal Calcification Diamond coated instrument rt 1 designed for better visibility and cutting efficiency a) Very powerful for efficient

What is Imbibition The ability of colloids to pick up water and swell when they come in contact with water is called imbibition. Imbibition is usually accompanied by the evo

Economic and ecological importance of protozoans

Define Prevalence and Incidence for anorexia nervosa? The disorder occurs most commonly in adolescent girls and young women, but adolescent boys and young men may be affected m

What is the condition for Mendel's second law to be valid? Mendel's second law is only valid for genes located in dissimilar chromosomes. For genes situated in the same chromos

Enumerate about the Baule unit  A mathematician from Gottingen by the name of B. Baule assisted Mitscherlich with his calculations.  The quantity of any growth factor (nutrient

Explain the PS In VCD in Cyanotic Heart Disease ? These are peculiar to this group only. It occurs in young infants (usually after two months and rarely after two years), It co

Chloroplast In plants, chloroplasts are the essential organelles for carrying out photosynthesis. Chloroplasts are found in all green plants. Chloroplast occurs mainly