Steroid and thyroid hormones, Biology

Assignment Help:

Steroid and Thyroid Hormones

Cytoplasmic receptors for steroids are proteins with two subunits that bind to the steroid molecules. When both receptor sites are occupied by the steroid then the receptor-steroid complex migrates to the nucleus where one subunit ensures that the complex binds to the specific site on the chromatin. Then the receptor subunits separate and the other subunit interact directly with the adjacent region of DNA molecule resulting in the transcription of the DNA segment into mRNA.

Thyroid hormone acts in a similar manner except that the receptor is located in the nucleus. The major hormone secreted by thyroid is thyroxine (T4). It travels in blood attached to carrier proteins. Thyroid also secretes a small amount of triiodothyronine (T3). Carrier proteins have higher affinity for T4 and very little T4 is free in the plasma. Only the free T4 and T3 enter the cells. The rest of the bound T4 acts as a reservoir for slow release. The free T4 that enters the cell s also converted to T3 enzymatically. Therefore, T3 is the chemically more potent and active form of thyroid hormone.

552_Steroid and Thyroid Hormones.png

Figure:Steroid and Thyroid Hormones


Related Discussions:- Steroid and thyroid hormones

What are the lethal genes, What are the lethal genes? The Lethal genes ...

What are the lethal genes? The Lethal genes are genes having at least one allele that, while present in the genotype of an individual, causes death. There are dominant lethal a

Explain the combating drug-resistant diseases, Explain the Combating drug-r...

Explain the Combating drug-resistant diseases? The growth of drug-resistant strains of disease-causing bacteria threatens the current effectiveness of cheap antibiotics. This i

Determine the chemical synaptic transmission, During chemical synaptic tran...

During chemical synaptic transmission A. neurotransmitter travels via diffusion in extracellular space. B. there will always be release of neurotransmitter from the postsyna

Explain the regulation of breathing and blood pressure, Which is the brain ...

Which is the brain region responsible for the regulation of breathing and blood pressure? The neural regulation of breathing, blood pressure and other physiological parameters

Features of plant and animal cell, Features of Plant and Animal Cell ...

Features of Plant and Animal Cell However plant and animal cells also differ. One of the most prominent features of the plant cell is its huge vacuoles filled with cell sap.

Enumerate the number of converging developments, Enumerate the Number of co...

Enumerate the Number of converging developments These include: 1) A better definition of the unique developmental concepts that are applicable to infants and young children,

Method of dna techonology tp improve lives of humans, List three ways that ...

List three ways that DNA technology could be used to improve the lives of humans. Answers could include: identifying human remains, determining a person's paternity, tracing h

What are the main characteristics of the age pyramids, What are the main ch...

What are the main characteristics of the age pyramids of developed countries? In a stabilized human population the age pyramid has a narrower base as the reproduction rate is

Introduction to heart surgery, INTRODUCTION :  It took just hundred years ...

INTRODUCTION :  It took just hundred years for cardiac surgery to advance to what it is today. Before 1896, surgeons considered heart to be "inviolable" and it was stated that ope

Nutrition, examples of heterotrophic nutrition

examples of heterotrophic nutrition

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