Postulate of Darwin

Geometric increase 

Limited food & Space

Struggle for existence 

Variation 

 Natural selection

Inheritance of useful characters

Speciation

TLS Online TPP Program

#Id: 8913

#XL - T Zoology

APC/CCdc²⁰ is inhibited by a checkpoint pathway that ensures that anaphase is not initiated until all chromosomes have achieved proper attachment to the mitotic apparatus.

TLS Online TPP Program

#Id: 9702

#XL - T Zoology

Haploid yeast cells secrete protein signals known as pheromones, which induce mating between opposite mating types.

TLS Online TPP Program

#Id: 7918

#XL - Q Biochemistry

TLS Online TPP Program

#Id: 10595

#XL - R Botany

Life Cycle of bryophytes will not complete in the absence of water, thus they are called as the “Amphibians of the plant kingdom”

TLS Online TPP Program

#Id: 10291

#XL - Q Biochemistry

The second phase of T-cell development

1.Positive selection: Selection for those cells whose T-cell receptors engage self-MHC.

2.Negative selection: Selection against those cells whose T-cell receptors bind too strongly to self-peptide/MHC combinations.

3.Lineage commitment: Commitment of thymocytes to effector cell lineages, including CD4 helper or CD8 cytotoxic populations