UCSD EXTENSION BIOCHEM QUIZ ONE BOARD EXAMINATION SET 2026 CORRECT ANSWERS GRADED A+

UCSD EXTENSION BIOCHEM QUIZ ONE
BOARD EXAMINATION SET 2026 CORRECT
ANSWERS GRADED A+

⩥ Which nitrogenous bases are the Pyrimidines? And where do they
form bonds to a sugar?
Answer: Cytosine
Uracil
Thymine


via their N1 atoms


⩥ How are pyrimidines numbered?
Answer:


⩥ Which nitrogenous bases are the Purines? And where do they form
bonds to a sugar?
Answer: Adenine
Guanine


via their N9 atoms

,⩥ How are purines numbered?
Answer:


⩥ Adenine structure
Answer:


⩥ Cytosine structure
Answer:


⩥ Guanine structure
Answer:


⩥ Thymine structure
Answer:


⩥ Uracil structure
Answer:


⩥ What is a nucleoside?
Answer: nitrogenous base + sugar


⩥ Adenosine structure

,Answer: adenine + sugar


⩥ Cytidine structure
Answer: cytosine + sugar


⩥ Guanosine structure
Answer: guanine + sugar


⩥ Thymidine structure
Answer: thymine + sugar


⩥ Uridine structure
Answer: uracil + sugar


⩥ What is the structure of ribose?
Answer: 2' OH


⩥ What is the structure of deoxyribose?
Answer: 2' H


⩥ Nucleotides are ________ _________
Answer: nucleoside phosphates

, ⩥ What makes up a nucleotide?
Answer: 1 phosphate group
1 deoxy/ribose sugar
1 nitrogenous base


many of these form DNA or RNA


⩥ DNA structure
Answer: deoxyribose + phosphate backbone w/ATCG bases making up
the ladder


always read in the 5' to 3' direction


MANY nucleotides form DNA


⩥ RNA structure
Answer: ribose + phosphate backbone w/AUCG bases making up the
ladder


always read in the 5' to 3' direction