Ib Dna Replication

Which is true about the relationship between enzymes and DNA?

• Both enzymes and DNA are made from proteins

• The base sequence of DNA is determined by which nucleotide DNA polymerase III attaches to the template strand

• The shape of a protein is due to the base sequence in the DNA that coded for it

• Both proteins and DNA are subject to denaturation

Answer explanation

Remember, DNA codes directly for proteins.

Tags

NGSS.HS-LS1-1

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

• amino acids

• nucleotides

• fatty acids

• polysaccharides

Answer explanation

Tags

NGSS.HS-LS1-1

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

• cytosine
• guanine
• thymine
• uracil

Answer explanation

This is all thanks to our main man, Mr. Chargaff!

Replicate the following strand of DNA: 
AAT CAT GGA

• AAT CAT GGA
• TTA GTA CCT
• UUA GUA CCU
• GGA TAU CUA

Answer explanation

You need to know the which base pairs with which, there are no two ways around it.

Which is the order of replication?

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

Answer explanation

#1 break the h-bonds between the bases.

#2 after adding a primer, build each new strand by using the template strand and following complimentary base pairing.

#3 voila! We end up with two identical DNA strands which are semiconservative.

Tags

NGSS.HS-LS3-2

The enzyme that attaches the complimentary base pairs to the original strand of DNA is called...

• helicase

• DNA polymerase III

• replicase

• synthase

Answer explanation

The type of DNA polymerase is DNA polymerase III, but don't stress too much about it.

Tags

NGSS.HS-LS1-1

The enzyme that breaks the hydrogen bonds between the bases to prepare for replication....

• helicase

• replicase

• DNA polymerase III

• ligase

Answer explanation

Remember, helicase breaks the helix.

Nitrogenous bases are joined by which type of bond?

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

Answer explanation

Hydrogen bonds are temporary which allows us to access the bases with relative ease.

Tags

NGSS.HS-LS1-1

If a DNA molecule is 18% Guanine which of the following is correct?

• 18% cytosine, 32% adenine, 32% thymine
• 32% cytosine, 18% adenine, 32% thymine
• 18% cytosine, 64% adenine, 64% thymine
• 32% cytosine, 32% adenine, 18% thymine

Answer explanation

18% G = 18% C (36% total)

32% A = 32% T (64%total)

Tags

NGSS.HS-LS1-1

The term used to describe DNA Replication is.....

• Semi-Conservative
• Conservative
• Anti-Parallel
• Parallel

Answer explanation

It is semi-conservative because part of the original DNA has been conserved in the new strand.