02.1

Which nitrogenous base is classified as a purine?

• Cytosine

• Thymine

• Adenine

• Uracil

Tags

NGSS.HS-LS1-1

In terms of structure, purines have:

• Two rings
  
  

• One ring
  
  

• Three rings
  
  

• No rings

What is a nucleoside composed of?

• A nitrogenous base and a phosphate group
  
  

• A nitrogenous base and a sugar
  
  

• A sugar and a phosphate group
  
  

• A nitrogenous base, sugar, and phosphate group

Which of the following is formed when a nucleoside is linked with one or more phosphate groups at the C-5 position of the ribose?

• Carbohydrate

• Nucleic acid

• Amino acid

• Nucleotide

Which of the following correctly describes a key structural difference between DNA and RNA?

• DNA contains uracil, while RNA contains thymine.

• DNA is single-stranded, while RNA is double-stranded.

• DNA has deoxyribose sugar, while RNA has ribose sugar.

• DNA is made of amino acids, while RNA is made of nucleotides.

Tags

NGSS.HS-LS1-1

How many hydrogen bonds are formed between guanine and cytosine in a DNA molecule?

• 1

• 2

• 3

• 4

What is the primary difference between ribose and deoxyribose sugars in nucleic acids?

• Ribose has one less carbon atom than deoxyribose.

• ) Deoxyribose lacks a hydroxyl (-OH) group at the 3' carbon.

• Deoxyribose is found in RNA, while ribose is found in DNA

• Ribose has a hydroxyl (-OH) group at the 2' carbon, while deoxyribose has a hydrogen (H) at the same position.

Why do AT rich regions of DNA denature more easily than GC rich regions?

• AT pairs are less common in the major groove of DNA than GC pairs.

• AT pairs have weaker covalent bonding compared to GC pairs.

• AT pairs contain less hydrogen bonds than GC pairs.

• AT pairs are more susceptible to mutations than GC pairs.

Which form of DNA is the most common under normal physiological conditions?

• A-form

• B-form

• Z-form

• C-form

Why do proteins typically bind to the major groove of DNA rather than the minor groove?

• The major groove is larger and has distinguishable functional groups.

• The major groove contains more hydrogen bonds that can be broken easily.

• The minor groove is highly acidic, preventing protein binding.

• Proteins can only recognize phosphate groups in the major groove.

Tags

NGSS.HS-LS1-1