Promotion - stages of carcinogenesis, Biology

Assignment Help:

Promotion - Stages of carcinogenesis

The second stage or promotion is reversible and does not include changes in structure of DNA but rather in the expression of the genome of the initiated cell. This results from an interaction among the changed DNA structure and some environmental factors termed 'promoting agents'. The stage of promotion needs extended interaction with the promoting agent, if the third stage of progression is to be teached. Figure describes the process of promotion in a simplified way. A single application of an initiator to the skin of a mouse produces initiated cells but no tumor

1743_Promotion.png

Figure:  The concept of initiation and promotion 

(a) However, if the initiator is applied to the skin first then subsequent application of the promoter results in tumor

(b) If the promoter is withdrawn the tumor regresses leaving behind initiated cells and continued application of promoter on tumor bearing skin lends to invasive carcinoma.

(c) The application of a promoter alone to the skin also does not produce tumor

(d) If the promoter is applied before the initiator is applied even then no tumor is formed.


Related Discussions:- Promotion - stages of carcinogenesis

The salt concentration is higher than that of acid, Which of the following ...

Which of the following statements about buffers is true? Select one: a. A buffer composed of a weak acid of pKa = 5 is stronger at pH 4 than at pH 6. b. At pH values lower

How the type of sport influence protein requirements, How the type of Sport...

How the type of Sport influence protein requirements? The type of sport and total calorie intakes influence protein requirements. Eating sufficient foods to meet high energy re

What are the biotolerant materials, What are the Biotolerant materials ...

What are the Biotolerant materials Biotolerant materials, are characterized by a thin fibrous tissue interface. The fibrous tissue layer develops as a result of the chemical pr

What are the three qualities specific to colour vision, What are the three ...

What are the three qualities specific to colour vision There are three qualities specific to colour vision- hue, saturation, and brightness. Hue: Hue is the function of a wa

Expain kingdom fungi, Kingdom Fungi Fungi was earlier placed with the t...

Kingdom Fungi Fungi was earlier placed with the true plants and are still largely considered so in the domain of botanists yet they are quite different. They are multicellular

Freshwater animals, Freshwater Animals In Figure you have seen that th...

Freshwater Animals In Figure you have seen that the body fluids of freshwater animals are hyperosmotic to their aqueous surroundings. This results in two-kinds of osmotic prob

Cellulose, why can only one kind of cellulose be formed?

why can only one kind of cellulose be formed?

Define physiology cohesion and adhesion theory, Define Physiology: Cohesion...

Define Physiology: Cohesion & Adhesion Theory? Transport in Plants :  Transport of water, minerals and nutrients within vascular plants is dramatically different from animals

Define role in growth and cellular differentiation, Define Role in growth a...

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

Human milk composition and infant growth and development, Explain the Human...

Explain the Human Milk Composition and Infant Growth and Development? This sub-section deals with composition of human milk, compares human milk with cow's milk and why human m

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