AP Bio - 1st Semester Exam 24 - 25 - 18 Dec 24

Front

What are the four nitrogenous bases in DNA?

Back

The four nitrogenous bases in DNA are adenine (A), guanine (G), cytosine (C), and thymine (T).

Front

What type of bond connects nucleotides in a DNA strand?

Back

Nucleotides in a DNA strand are connected by covalent bonds between the phosphate group of one nucleotide and the deoxyribose sugar of the next.

Front

What is mismatch repair in DNA?

Back

Mismatch repair is a form of DNA repair in which non-complementary nucleotides are recognized, excised, and replaced with correct nucleotides.

Front

What are Okazaki fragments?

Back

Okazaki fragments are short stretches of DNA synthesized on the lagging strand during DNA replication.

Front

What is the role of DNA polymerase?

Back

DNA polymerase is an enzyme that synthesizes new DNA strands by adding nucleotides complementary to the template strand.

Front

Define purines and give examples.

Back

Purines are nitrogenous bases with a double-ring structure; examples include adenine (A) and guanine (G).

Front

Define pyrimidines and give examples.

Back

Pyrimidines are nitrogenous bases with a single-ring structure; examples include cytosine (C) and thymine (T).

Front

What is the significance of the 5' and 3' ends of a DNA strand?

Back

The 5' end has a phosphate group, while the 3' end has a hydroxyl group; DNA strands are antiparallel, meaning one runs 5' to 3' and the other 3' to 5'.

Front

What is the function of helicase in DNA replication?

Back

Helicase is an enzyme that unwinds the DNA double helix, separating the two strands to allow replication.

Front

What is the difference between leading and lagging strands in DNA replication?

Back

The leading strand is synthesized continuously in the direction of the replication fork, while the lagging strand is synthesized in short segments (Okazaki fragments) away from the fork.