Unit 7 | Molecular Biology

DNA is composed of:

• Amino acids

• Fatty acids

• Nucleotides

• Glucose molecules

What are the three parts of a nucleotide in DNA?

• a) Ribose sugar, phosphate group, nitrogenous base

• b) Deoxyribose sugar, phosphate group, nitrogenous base

• c) Amino acid, peptide bond, carboxyl group

• d) Glucose, fructose, sucrose

The nitrogenous bases in DNA are held together by what type of bond?

• Covalent bonds

• Ionic bonds

• Hydrogen bonds

• Van der Waals forces

Which of the following is a key difference in DNA replication between prokaryotes and eukaryotes, based only on DNA shape/location?

• Eukaryotic DNA replication is semiconservative, while prokaryotic is not.

• Prokaryotes have multiple origins of replication.

• Prokaryotic DNA is circular and located in the cytoplasm, while eukaryotic DNA is linear and resides within the nucleus.

• Prokaryotic DNA replication involves Okazaki fragments.

DNA replication is described as a semiconservative process. What does this mean?

• The original DNA molecule is conserved, and a completely new molecule is synthesized.

• DNA replication results in three new strands and one old strand.

• Each new DNA molecule contains one original (old) strand and one newly synthesized strand.

• Portions of the original DNA molecule are dispersed within the newly synthesized molecules.

During DNA replication, which enzyme is responsible for unwinding the DNA double helix at the replication fork?

• a) DNA polymerase

• b) Primase

• c) Helicase

• d) Ligase

DNA polymerase synthesizes new DNA strands in which direction?

• 3' to 5'

• 5' to 3'

• Both directions simultaneously

• It depends on whether it is the leading or lagging strand.

The lagging strand is synthesized in short fragments called

• Replication bubbles

• Primers

• Okazaki fragments

• Nucleotides

What is the role of DNA ligase in DNA replication?

• a) To add RNA primers to the template strand.

• b) To unwind the DNA double helix.

• c) To synthesize new DNA nucleotides.

• d) To join the Okazaki fragments together.

What is the central dogma of biology?

• a) Protein -> RNA -> DNA

• b) RNA -> DNA -> Protein

• c) DNA -> RNA -> Protein

• d) DNA -> Protein -> RNA

Tags

NGSS.HS-LS1-1