TLS Online TPP Program

#Question id: 3607


Cystic fibrosis is caused by a recessive lethal gene and can be detected by an excess concentration of chloride in sweat. If a sweat test reveals a man to be heterozygous and his wife to be homozygous normal, what are the chances that their children will have the disease?

#Unit 8. Inheritance Biology
  1. 1/2 of the children will have cystic fibrosis.

  2. None of their children will have cystic fibrosis.

  3. All of the children will have cystic fibrosis.

  4. All of their children will have Carrier

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TLS Online TPP Program

#Question id: 2827

#Unit 2. Cellular Organization

Two related genes that are derived from a gene duplication event are considered to be

a. homologous.                                   

b. paralogous.

c. orthologous.                       

d. members of a gene family.

TLS Online TPP Program

#Question id: 2828

#Unit 2. Cellular Organization

A transcriptionally active gene compared with a transcriptionally inactive gene would be expected to

a. contain acetylated histones.           

b. contain unacetylated histones.

c. be sensitive to DNase I.                 

d. be resistant to DNase I.

TLS Online TPP Program

#Question id: 2829

#Unit 2. Cellular Organization

Scaffold-associated regions

a. are the chromosome attachment points for the mitotic spindle.

b. can insulate transcription units from each other.

c. are the points at which DNA interacts with histone proteins.

d. are found between transcription units.

TLS Online TPP Program

#Question id: 2830

#Unit 2. Cellular Organization

The NtrC protein from E. coli
a. is a σ54 RNA polymerase.             
b. stimulates transcription of the glnA gene.
c. is activated by a protein kinase called NtrB.
d. binds both to an enhancer site upstream of the glnA gene and to RNA polymerase.
e. has ATPase activity.

TLS Online TPP Program

#Question id: 2831

#Unit 2. Cellular Organization

Specific DNA control elements in promoters can

a. interact with general transcription factors.

b. interact with repressor proteins.                 

c. interact with activator proteins.

d. remain unavailable because of condensed chromatin. 

TLS Online TPP Program

#Question id: 2832

#Unit 2. Cellular Organization

Reporter genes are used to

a. express enzymes that are not easily assayed in cell extracts.

b. express enzymes that are easily assayed in cell extracts.

c. characterize DNA control elements.                     

d. characterize reporter plasmids.