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TLS Online TPP Program

#Question id: 12482

The Rb protein has been called the “master brake” of the cell cycle. How the Rb protein acts as a cell cycle brake?

#Unit 2. Cellular Organization
  1. Rb bound to E2F and function as transcriptional repressors because Rb recruits chromatin-modifying enzymes that promote deacetylation and methylation of specific histone lysines, causing chromatin to assume a condensed, transcriptionally inactive form.
  2. S phase CDKs and mitotic CDKs maintain Rb protein in the phosphorylated state throughout the S, G2, and early M phases.
  3. Rb bound to E2F and promotes ubiquitinylation of E2F and inhibits chromosomal segregation.
  4. Rb bound to E2F and promotes acetylation which prevents unloading of cohesins.
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TLS Online TPP Program

#Question id: 4817

#Unit 8. Inheritance Biology

How many different gametes can be formed by an organism with genotype AaBbCCddEe, If a, b and c gene are completely link?
TLS Online TPP Program

#Question id: 4819

#Unit 8. Inheritance Biology

Plant with genotype AB/ab is test cross, two genes are linked are 10 map units apart. What proportion of progeny will have the genotype aabb?
TLS Online TPP Program

#Question id: 4820

#Unit 8. Inheritance Biology

Which of the following gametes are produced in grater proportional by an individual of genotype Ab/aB if the genes are in the same chromosome with some recombination between them?
TLS Online TPP Program

#Question id: 4821

#Unit 8. Inheritance Biology

What are frequency of recombination  if one cell carry out cross over every 50 cell undergoes meiosis ?
TLS Online TPP Program

#Question id: 4822

#Unit 8. Inheritance Biology

In a particular species of mammal black hair (B) is dominant to green hair (b) and red eyes (R) are dominant to white eyes (r). If a BbRr individual is mated with a bbrrindividual the expected phenotypic ratio of the offspring is 1 black-red : 1 black-white: 1 green-red : 1 green-white. However, when you mate these individuals you find that the phenotypic ratio of the offspring is 6 black-red :1 black-white : 1 green-red : 6 green-white. What could account for this difference?
TLS Online TPP Program

#Question id: 4823

#Unit 8. Inheritance Biology

Which one of the following DNA markers can be used to distinguish between a homozygote and heterozygote ?