Semester 2 review

Which of the following units are repeatedly joined together to form a strand of DNA?

• amino acids
• nucleotides
• fatty acids
• polysaccharides

The enzyme that unzips the DNA to prepare for replication

• helicase
• replicase
• polymerase
• synthase

DNA replication results in two DNA molecules,

• each one with two original strands
• each one with two new strands
• each one with one new strand and one original strand
• one with two new strands and the other with two original strands

Which of the following must happen first in order for DNA replication to occur?

• DNA polymerase binds to the leading strand
• DNA is unwound
• Hydrogen bonds form between bases
• chromosomes condense

Which sequence of DNA bases would pair with this partial strand
ATG TGA CAG

• ATG TGA CAG
• TAC ACT GTC
• GTA AGT GAC
• CAT TCA CTG

In a molecule of double-stranded DNA, the amount of Adenine present is always equal to the amount of

• cytosine
• guanine
• thymine
• uracil

Which organelle is DNA usually found in?

• cell membrane
• vacuole
• chloroplast
• nucleus

Nitrogenous bases are joined by which type of bond?

• polar bonds
• ionic bonds
• covalent bonds
• hydrogen bonds

order of replication

• 3, 2, 1, 4
• 2, 1, 4, 3
• 2, 3, 1, 4
• 3, 4, 1, 2

Why is it crucial that living things are able to replicate their DNA?

• Each cell must have its own DNA
• Less copies of DNA are needed when a new cell is created
• A cell needs multiple copies of DNA
• Only muscle cells need DNA