Agglutination reactions are similar in principle to precipitation reactions they depend on the crosslinking of polyvalent antigens. Just as an excess of antibody inhibits precipitation reactions, such excess can also inhibit agglutination reactions; this inhibition is called the prozone effect.

TLS Online TPP Program

#Id: 3208

#Unit 4. Cell Communication and Cell Signaling

Mutations in three broad classes of genes play key roles in cancer induction:
Proto-oncogenes genes
Tumor-suppressor genes
Genome maintenance genes

TLS Online TPP Program

#Id: 3209

#Unit 4. Cell Communication and Cell Signaling

Dominant gain-of-function mutations in proto-oncogenes and recessive loss-of-function mutations in tumor-suppressor genes are oncogenic.

TLS Online TPP Program

#Id: 3210

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 3211

#Unit 4. Cell Communication and Cell Signaling

Three mechanisms can produce oncogenes from the corresponding proto-oncogenes:
Point mutation
Chromosomal translocation
Amplification

TLS Online TPP Program

#Id: 3212

#Unit 4. Cell Communication and Cell Signaling

Point mutation (i.e., a change in a single base pair) in a proto-oncogene that results in a hyperactive or constitutively active protein product.

TLS Online TPP Program

#Id: 3213

#Unit 4. Cell Communication and Cell Signaling