Brain neurosecretory cells and their hormones, Biology

Assignment Help:

Brain Neurosecretory Cells and their Hormones

Kopec was the very first to suggest the role of hormones in controlling metamorphosis. On the base of his experiments on the larval gypsy moth (Porthetria dispar) he observed that at a specific period the brain releases a substance into the blood which is essential for pupation and therefore for metamorphosis. His findings on the role of brain hormones in metamorphosis of insects was supported by consequent workers who found similar mechanisms in dissimilar insect groups. Large secretory nerve cells in the brain of the insects called neurosecretory nerves were as well identified as being responsible for affecting pupation. The secretion of these cells is known as activation hormone (AH) or brain hormone (BH). The activation hormone is comprised of proteins or Lipoproteins. The AH or BH after synthesis pass together the axons of these cells and end blindly into a pair of storage and release organs called the corpora cardiaca (CC), situated in the posterior brain. The CC releases the active hormone material termed as prothoracicotropic hormone (PTTH) which is a small polypeptide. This prothoracicotropic hormone acts on the prothoracic gland, causing it to secrete the moulting hormone known as 'ecdysone'.


Related Discussions:- Brain neurosecretory cells and their hormones

Mycotoxins, Fungi are a very diverse group of organisms and have a signific...

Fungi are a very diverse group of organisms and have a significant impact on the production, spoilage and safety of food. Molds have not only served to synthesize antibiotics but a

Genetics , Genetics Genetics is the study of heredity. It is an ancien...

Genetics Genetics is the study of heredity. It is an ancient discipline. At least 4000 years ago, in Sumeria, Egypt and other parts of the world, farmers recognized that they

Define reagents for seliwanoff test, Define Reagents for seliwanoff's tes...

Define Reagents for seliwanoff's test? - Sugar solutions of glucose, fructose, galactose, lactose, maltose, sucrose and starch - Resorcinol in dilute hydrochloric acid (1:

Explain water as a lubricant, Explain Water as a lubricant? All fluids...

Explain Water as a lubricant? All fluids have lubricating as they can make it easier for the solid materials to slip over one another. Water-based fluids act as lubricants in

Define requirements for underwater weighing method, Define Requirements for...

Define Requirements for underwater weighing method? • The equipment required to perform hydrostatic measurements is bulky and maintenance intense. • A large tank of water, usu

Oxygen stratification - lake ecosystem, Oxygen Stratification - Lake Ecosys...

Oxygen Stratification - Lake Ecosystem In most lakes, oxygen stratification nearly parallels that of temperature during the summer season. The amount of oxygen is greatest on

Determine the muscarinic acetylcholine receptors, Which of the following se...

Which of the following serves as an effector, or as part of an effector, that functions in a negative feedback system? A. Muscarinic Acetylcholine Receptors (mAChRs) in the SA

Define anaemia in pregnancy, Define Anaemia in Pregnancy? Anaemia is th...

Define Anaemia in Pregnancy? Anaemia is the most common complication and is often compounded by low socio- economic status. However, it is seen frequently in upper income women

Cellulose, Cellulose is a polysaccharide which is composed of the unbranch...

Cellulose is a polysaccharide which is composed of the unbranched chains of glucose; the major structural carbohydrate of the plants, insoluble in water, and indigestible in the h

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