Ch07

DNA

A molecule of nucleic acid that stores the information needed to produce proteins and is composed of nucleotide subunits.

Nucleotide

The monomer subunit of DNA and RNA, consisting of a phosphate group, a sugar (deoxyribose in DNA, ribose in RNA), and a nitrogenous base.

Transcription

The process of synthesizing RNA from a DNA template, which occurs in the nucleus.

Translation

The process in which ribosomes synthesize proteins by interpreting the information carried by messenger RNA (mRNA).

Codon

A sequence of three nucleotides in mRNA that encodes a specific amino acid.

Anticodon

A three-nucleotide sequence in tRNA that base pairs with a corresponding codon in mRNA.

Operon

A cluster of genes in prokaryotes that are regulated together and transcribed as a single mRNA.

Intron

A non-coding sequence of DNA that is removed from the pre-mRNA during RNA processing.

Exon

A coding sequence of DNA that remains in the mRNA after intron removal and is expressed in the protein.

Repressor protein

A regulatory protein that binds to an operator region of DNA to inhibit transcription.

Mutation

A change in the DNA sequence that can result in alterations to protein structure and function.

Frameshift mutation

A mutation that involves insertion or deletion of bases, leading to a shift in the reading frame of the genetic code.

Hershey and Chase experiment

An experiment that demonstrated that DNA is the genetic material by using bacteriophages.

Complementary base pairing

The principle that adenine pairs with thymine (A-T) and guanine pairs with cytosine (G-C) in DNA.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template during transcription.

What is DNA's primary function?

To store genetic information necessary for the development and functioning of living organisms.

What are the components of a nucleotide?

A phosphate group, a sugar (deoxyribose in DNA), and a nitrogenous base.

Where does transcription occur?

In the nucleus of the cell.

What role do ribosomes play in translation?

They synthesize proteins by interpreting mRNA.

How many nucleotides are in a codon?

Three nucleotides.

What is the purpose of an anticodon?

To base pair with its corresponding codon in mRNA during protein synthesis.

What is an operon?

A cluster of genes in prokaryotes regulated together, transcribed as a single mRNA.

What is an intron?

A non-coding sequence of DNA that is removed during RNA processing.

What is an exon?

A sequence of DNA that codes for a protein and remains in the mRNA after splicing.

What does a repressor protein do?

It binds to an operator region of DNA to inhibit transcription.