Question

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QUESTION 1 A cell can change the expression of its genes in response to external signals. O True False QUESTION 2 Different cell types that respond to the same environmental stimulus would most likely turn on a different set of genes in responce. O True O False QUESTION 3 DNA polymerase can be considered a house-keeping protein. True False

Answer 1

Ans) 1) True

Explaination:

Cells can change the pattern of genes they express in response to changes in their environment, such as signals from other cells.

2) True

Explaination:

Different cell types that respond to the same hormone usually turn on the different sets of genes in response.

3) False

Explaination:

"House keeping" proteins":

- Typically constitutive genes are required for the maintenance of basic cellular function- expressed in all cells of an organism.

Eg. RNA polymerases and ribosomal proteins, essential for transcribing and translating the DNA into proteins.

- DNA polymerase is an enzyme that synthesizes DNA molecules from deoxyribonucleotides, the building blocks of DNA.

4) A prokaryotic feature, an operon is a sequence of DNA that produces multiple mRNA molecules.

Explaination:

Prokaryotic DNA is clustered into groups of genes called operons.