Define role in growth and cellular differentiation, Biology

Assignment Help:

Define Role in growth and cellular Differentiation?

The growth and differentiation of epithelial cells throughout the body are especially affected by vitamin A deficiency.  In addition, goblet cell numbers we reduced in epithelial tissues and as a consequence, mucous secretions diminish. Cells lining protective tissue surfaces fail to regenerate and differentiate; hence they flatten and accumulate keratin.  Classical symptoms of xerosis (drying or non-wet ability) and desquamation of  dead surface cells as seen in ocular tissue (i.e. xerophthalmia) are the external  evidence of the changes also occurring to various degrees in internal epithelial  tissues. Current understanding of the mechanism of vitamin A action within cells outside the visual cycle is that cellular functions are mediated through specific nuclear receptors. Binding with specific isomers of retinoic acid (i.e.all Tran- and 9-cis-retinoic acid) activates these receptors. Activated receptors bind to DNA response elements located upstream of specific genes to regulate the level of expression of those genes. These retinoid-activated genes regulate the synthesis of a large number of proteins vital to maintaining normal physiologic functions. There may, however be other mechanisms of action that are as yet undiscovered.

 


Related Discussions:- Define role in growth and cellular differentiation

Sour taste, Sour taste is usually due to the presence of acids such as acet...

Sour taste is usually due to the presence of acids such as acetic acid, citric acid, benzoic acid. Upon dissociation, the acids give H ions which impart acidity. More the H ion con

What is the role of radiographic evaluation, What is the role of radiograph...

What is the role of radiographic evaluation in implant treatment? Radiographic examination is very different with implants than with teeth. Radiographs are frequently used in i

Other complications of prosthetic valves, Other Complications of Prosthetic...

Other Complications of Prosthetic Valves :  One of the dreaded complications of mitral valve replacement is ventricular rupture. It is difficult to manage and so it is better avoi

Preservation of species diversity, Q. Preservation of species diversity? ...

Q. Preservation of species diversity? Genetic diversity is, thus, important for the preservation of species diversity, and hence biological diversity. A knowledge of the variab

Determine the organs of female reproductive system, What are the anatomical...

What are the anatomical relationships between the organs of the female reproductive system from the external vulva to the ovaries? The external female genitalia is called the v

Define principle for estimation of cholesterol - lipids, Define Principle f...

Define Principle for Estimation of cholesterol - Lipids? Zlatkis and associates have evolved a method of quantitative determination of cholesterol based on a reagent containing

Explain changes in body tissue compartments - underweight, Explain the Chan...

Explain the Changes in Body Tissue Compartments - Underweight? The severity of nutritional deprivation determines the extent of changes in the body tissue compartments. The fir

Benefits of hand washing, Benefits of Hand washing You wash hands as a ...

Benefits of Hand washing You wash hands as a routine in daily life before cooking and eating food, after using wash room/toilet, before touching and caring a new born baby, aft

Components of ecosystem, An ecosystem consists of two types of components: ...

An ecosystem consists of two types of components: (a)   Abiotic components: This includes the non-living components of the ecosystem. These are physical and chemical fact

How do bacteria reproduce, How do bacteria reproduce? Bacteria replicat...

How do bacteria reproduce? Bacteria replicate by binary fission (scissiparity). Some bacteria though present a kind of sexual reproduction (transformation, transduction or conj

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