we examine how the deregulation of growth-promoting and growth-inhibiting signaling pathways contributes to tumorigenesis. Mutations-

A. A mutation that alters a single amino acid (valine to glutamine) in the transmembrane region of the HER2 receptor

B. A deletion that causes loss of the extracellular ligand-binding domain in the EGF receptor Results-

i. dimerization of the receptor, even in the absence of the normal EGF-related ligand, transforming it into the oncoprotein, a constitutively active kinase

ii. to constitutive activation of the kinase activity of the resulting oncoprotein

iii. no dimerization, even in the presence of the normal EGF-related ligand, repression of kinase activity

which of the following results are displayed after these mutations?

TLS Online TPP Program

#Question id: 23888

#Unit 13. Methods in Biology

A recessive allele usually results from a mutation that

a. disrupts expression of the gene.

b. alters the structure of the encoded protein leading to gain of function.

c. alters the structure of the encoded protein leading to loss of function.

d. increases the activity of the encoded protein.

TLS Online TPP Program

#Question id: 23889

#Unit 13. Methods in Biology

Temperature-sensitive mutations would be particularly useful for studying which of the following processes?

a. DNA synthesis

b. hormone secretion

c. protein synthesis

d. Mitosis

TLS Online TPP Program

#Question id: 23890

#Unit 13. Methods in Biology

Which of the following is an essential element of plasmids used as cloning vectors?

a. a centromere

b. a telomere

c. an origin of replication

d. a drug resistance gene

TLS Online TPP Program

#Question id: 23891

#Unit 13. Methods in Biology

Which of the following is (are) used both in the polymerase chain reaction (PCR) and in DNA sequencing?

a. single-stranded DNA primers

b. deoxynucleotide triphosphates (dNTPs)

c. dideoxynucleotide triphosphates (ddNTPs)

d. DNA polymerase

TLS Online TPP Program

#Question id: 23892

#Unit 13. Methods in Biology

The restriction enzyme BglIl has the recognition sequence (A*GATCT) and cuts between the A and the G as indicated by the asterisk. DNA cut by which of the following restriction enzymes (given with their recognition sequences and cut sites) could be cloned into a plasmid cut with BgIII? 

TLS Online TPP Program

#Question id: 23893

#Unit 13. Methods in Biology

Which technique is the best for providing spatial information about gene expression in a tissue or organisms?