DNA Structure

How does DNA replication occur?

• DNA is copied directly from one strand to another without unwinding.

• DNA unwinds and each strand serves as a template for the formation of a new complementary strand.

• DNA replication occurs only during cell division.

• DNA is synthesized in the nucleus and then transported to the cytoplasm.

What are the four nitrogenous bases in DNA?

• Adenine, Thymine, Cytosine, Guanine

• Adenine, Uracil, Cytosine, Guanine

• Adenine, Thymine, Cytosine, Uracil

• Guanine, Thymine, Cytosine, Uracil

What is a gene?

• A segment of DNA that contains the instructions for making a specific protein.

• A type of RNA that helps in protein synthesis.

• A cellular structure that produces energy.

• A molecule that carries genetic information from one generation to the next.

The two strands of DNA are held together with

• ionic bonds

• covalent bonds

• hydrogen bonds

• disulfide bonds

What is the structure of a nucleotide?

• A nucleotide consists of a phosphate group, a sugar (deoxyribose), and a nitrogenous base.

• A nucleotide is made up of two phosphate groups and a ribose sugar.

• A nucleotide contains a sugar, a nitrogenous base, and a fatty acid.

• A nucleotide is composed of a phosphate group, a sugar, and an amino acid.

What is the role of hydrogen bonds in DNA structure?

• They hold the two strands of DNA together.

• They provide energy for DNA replication.

• They determine the sequence of nucleotides in DNA.

• They protect DNA from damage.

Which of the following is a base pair?

• Adenine - Thymine

• Cytosine - Guanine

• Uracil - Adenine

• Guanine - Thymine

The backbone of DNA is made of

• sugars and phosphates

• amino acids and sugars

• nucleotides and proteins

• fatty acids and glycerol

DNA is found within the _____________ of a cell.

• nucleus

• cytoplasm

• mitochondria

• ribosome

What is complementary base pairing?

• The specific pairing of adenine with thymine and cytosine with guanine.

• The random pairing of any nucleotide bases.

• The pairing of adenine with guanine and thymine with cytosine.

• The pairing of nucleotides with sugars in DNA.