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

Respiration in annelids, Describe the different types of respiratory organs...

Describe the different types of respiratory organs found in annelids.

Plasma membrane proteins, Integral plasma membrane proteins are also synthe...

Integral plasma membrane proteins are also synthesized by ribosomes on the RER, but become inserted in the rough endoplasmic reticulum membrane rather than transported into the lum

Kingdom, general characteristics of sponges

general characteristics of sponges

Determine biologically compatibility of implant materials, Biologically com...

Biologically compatibility od implant materials An ideal implant material will elicit mainly physiological reactions within the surrounding tissues (bone, connective tissue and

Respiration would cease even oxygen and food were supplied, If a tissue was...

If a tissue was heated to 65ºC for 10 minutes, respiration would cease even if oxygen and food were supplied. Why is this? A temperature of 65°C for 10 minutes would denature

Explain spray-dried milk powder, Q. Explain Spray-dried milk powder? Th...

Q. Explain Spray-dried milk powder? The milk which is concentrated by the process of spray drying contains about 40- 45% total solids. Do you know how the dried milk powder i

Define oven - nutritional biochemistry, Define Oven - Nutritional Biochemis...

Define Oven - Nutritional Biochemistry? Oven is a general term used to describe a chamber or enclosed compartment for heating, baking, or roasting food, as in a stove, or for f

Transport in plants, Osmosis and transpiration both play a part in the move...

Osmosis and transpiration both play a part in the movement of water through a plant. Which of these two processes makes the greater contribution to the movement of water up the t

Define fat requirement for cancer patients, Define Fat requirement for canc...

Define Fat requirement for cancer patients? During cancer there is enhanced mobilization of free fatty acids from adipose tissues resulting in subsequent depletion of total bod

Promoters - transgenic animals, Promoters The promoter region contains ...

Promoters The promoter region contains the DNA sequences that allow the formation of the transcription initiation complex that give the specificity of expression. Promoters are

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