Biology Test: DNA & Cell Cycle

Which part of a nucleotide contains the genetic code?

• Phosphate group

• Deoxyribose sugar

• Nitrogen base

• Hydrogen bond

In DNA, adenine always pairs with:

• Thymine

• Guanine

• Cytosine

• Uracil

What type of bond holds the nitrogen bases together in the middle of the DNA molecule?

• Covalent bond

• Hydrogen bond

• Ionic bond

• Peptide bond

The sides (backbone) of the DNA molecule are made of:

• Sugar and phosphate

• Bases and sugar

• Amino acids

• Hydrogen and oxygen

Which correctly describes the shape of DNA?

• Straight chain

• Double helix

• Single helix

• Spiral ladder

What is the purpose of DNA replication?

• To make RNA

• To make proteins

• To make an identical copy of DNA before cell division

• To destroy old DNA

Which enzyme “unzips” the DNA strands during replication?

• DNA ligase

• DNA helicase

• DNA polymerase

• RNA primase

DNA replication is described as semi-conservative because:

• Each new DNA has two new strands

• Each new DNA has one original strand and one new strand

• DNA copies are completely new

• It only happens halfway through the cell cycle

Which enzyme “glues” fragments of DNA together?

• Helicase

• Polymerase

• Ligase

• Transferase

Where in the cell does DNA replication occur?

• Cytoplasm

• Ribosome

• Nucleus

• Mitochondria