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

Internal mammary artery-long term patency, Internal Mammary Artery (1MA) : ...

Internal Mammary Artery (1MA) :  This is an excellent graft. When left internal mammary artery (LIMA) is anastomosed to LAD, which has more than 70 per cent block, patency at

Define nutrient and drug interaction, Define Nutrient and Drug Interaction?...

Define Nutrient and Drug Interaction? Modern medicine has given us many useful drugs that not only prolong and save lives but in fact improve the quality of our lives. Have you

Explain about the sugaring - methods of food processing, Explain about the ...

Explain about the Sugaring - methods of food processing? Water is withdrawn from the microbial cells when they are placed in a strong sugar solution (about 68%) and thus result

What is the type of reproduction that occurs in roundworms, What is the typ...

What is the type of reproduction that occurs in roundworms? What typical element do nematode sperm cells have? Nematodes reproduce sexually. The nematode sperm cell does not h

Population density - biological stress, Population Density - Biological Str...

Population Density - Biological Stress You are aware of what might follow an uncontrolled growth of human population. There will be competition for common consumables and for

Explain food intolerances, Food Intolerances Food Intolerances:  The in...

Food Intolerances Food Intolerances:  The intolerances of  the patient for specific food  items must be assessed. For example,  milk may lead  to diarrhoea  in some people whil

Define instrument for measurement of absorbed radiation, Define Instrument ...

Define Instrument for Measurement of Absorbed Radiation? a) Photometer: This is an instrument which it designed to measure the intensity of the beam of light and usually does s

Corpus allatum and prothoracic gland, Corpus Allatum and Prothoracic Gland ...

Corpus Allatum and Prothoracic Gland Corpus Allatum The corpus allatum is situated in the neck region of insects. It is generally a rounded, solid and translucent struc

Name the food require during thyphoid, Food require during thyphoid So ...

Food require during thyphoid So remember the foods to be included are: Juices, soups, dal water, broths. Refined cereals and their products (e.g. maida, rava, bread, rice

Chlamydiosis-clinical manifestations, Clinical manifestations Since the...

Clinical manifestations Since the disease due to Chlamydia involves many organs/systems, system-wise descriptions of clinical signs is described as under: Genital infectio

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