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

Cow-pox (vaccinia), C o w - po x (vaccinia) E p ide...

C o w - po x (vaccinia) E p idemiology: This infection, although mostly occurring in cows, sometimes also occurs in buffaloes. Under natural conditions, t

Is phenoxyethanol harmful?, Phenoxyethanol is dangerous and can be absorbed...

Phenoxyethanol is dangerous and can be absorbed through the skin - official sites for toxicity data, though, show little toxicity in man and some toxicity (irritation) with high do

Hormones of pancreas, HORMONE S OF PANCREAS AND THEIR ROLE - (i) Glu...

HORMONE S OF PANCREAS AND THEIR ROLE - (i) Glucagon (Secreted by a-cells) It stimulates the liver to convert stored glycogen into glucose. Glucagon is controlled b

Placenta - human development, Placenta - Human Development We had said...

Placenta - Human Development We had said previous in the unit that in the second week of development a primitive uteroplacental circulation is established. Early in this stage

Reflex action, REFLE X ACTION - Marshel Hall discovered reflex ac...

REFLE X ACTION - Marshel Hall discovered reflex action. Best & Taylor defined it. Reflex action is functional unit of CNS. It is sudden, immediate involuntary acti

Enumerate the anatomic consequences of edentulism, Q. Enumerate the anatomi...

Q. Enumerate the anatomic consequences of edentulism? The anatomic consequences of edentulism include the effect of edentulism on bone and soft tissues. Basal bone forms the de

Different areas of brain, Different areas of brain - HUMA N...

Different areas of brain - HUMA N BRAIN DIFFEREN T AREAS OF BRAIN Note : - In brain glutemic acid metabolins is common In latemaria brain's size

Do you know what the recommendations for fibre are, Do you know what the re...

Do you know what the recommendations for fibre are? Well, the crude fibre intake should be 14 g/1000 Kcal. For adult woman 25 g/day and for adult man 38 g/day is desirable.

Number of chromosomes, NUMBER Benden and Boveri first indicated tha...

NUMBER Benden and Boveri first indicated that number of Chromosomes is definite in each organism. (1) Haploid (n) - One set of Chromosomes. i.e. one Chromosome of each

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