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 is the ability of two oxygens to remove h+ protons, What makes the clu...

What makes the cluster of atoms of carboxylic acid functional group an acid? a) a non-polar O-H bond near another electronegative oxygen. b) an ionic O-H bond near another el

Describe the basic types of leukocytes, Q. What are the kinds of leukocytes...

Q. What are the kinds of leukocytes and how are they classified into granulocytes and agranulocytes? The kinds of lymphocytes are leukocytes, neutrophils, monocytes, basophils

Class of subphylum uniramia - pauropoda, Class of Subphylum Uniramia - Paur...

Class of Subphylum Uniramia - Pauropoda A small group of uniramians, there are 500 species of Pauropoda explained so far. The minute organisms computing about 1.5 mm in length

Which protein component include organic matter of skin, This main protein c...

This main protein component of connective tissue in mammals includes most of the organic matter of skin, bones, tendons, and teeth and occurs as fibrous inclusions in most other bo

Loudness, The sound levels of power, intensity and pressure are the physica...

The sound levels of power, intensity and pressure are the physical effects which the human ear receives, it is not, however, what the person perceives. What is being perceived or h

Explain about nutritional recommendations for healthy ageing, Explain about...

Explain about the Nutritional recommendations for Healthy Ageing? You would recall reading about meal planning during various stages of life, spanning right from the infancy ti

Composition of blood, Composition of blood: Take few ml. of fresh bl...

Composition of blood: Take few ml. of fresh blood in a test tube and before collecting the blood add a few drops of sodium oxalate or sodium citrate solution to prevent clot

How cycling is beneficial for proper health, How Cycling is beneficial for ...

How Cycling is beneficial for proper health Cycling is best for maintenance of fitness. It is a popular exercise and can be done by individual of all ages. Bicycle is required

Determine about the sense of contrast, Determine about the Sense of  Contr...

Determine about the Sense of  Contrast It is  the ability to  perceive  slight changes  in  luminance between  regions which  are not  separated by  definite borders. This  is

Define the historical process of spatial processes, Define the Historical P...

Define the Historical Process of Spatial processes? In year 1952 Alan Turing developed his theory of the generation of pattern in systems of reaction diffusion equations, now k

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