Nucleic acids - structure & function

Question 1

What nitrogenous base is found in RNA instead of thymine?

Answer 1

Uracil (U)

RNA contains uracil (U) in place of thymine (T), which is found in DNA.

Question 2

What type of sugar is present in RNA?

Answer 2

Ribose

RNA contains ribose, whereas DNA contains deoxyribose.

Question 3

How many polynucleotide strands does RNA consist of?

Answer 3

One polynucleotide strand

RNA is single-stranded, unlike DNA which is double-stranded.

Question 4

How does the length of RNA polynucleotide chains compare to DNA?

Answer 4

Relatively short

RNA molecules are generally shorter than DNA molecules.

Question 5

What is the pentose sugar found in DNA?

Answer 5

Deoxyribose

DNA contains deoxyribose as its sugar component.

Question 6

List the nitrogenous bases found in DNA.

Answer 6

• Adenine (A)
• Cytosine (C)
• Guanine (G)
• Thymine (T)

These four bases are the building blocks of DNA.

Question 7

What is the structure of DNA in terms of strands?

Answer 7

Double-stranded (double helix)

DNA forms a double helix structure with two strands.

Question 8

What does complementary base pairing refer to?

Answer 8

Specific pairing of DNA bases

Adenine pairs with Thymine, and Cytosine pairs with Guanine.

Question 9

How many hydrogen bonds form between adenine and thymine?

Answer 9

Two hydrogen bonds

This bonding contributes to the stability of the DNA structure.

Question 10

How many hydrogen bonds form between cytosine and guanine?

Answer 10

Three hydrogen bonds

This stronger bond contributes to the stability of DNA.

Question 11

What role does one DNA strand play in relation to the other during replication?

Answer 11

Acts as a template

One strand serves as a template for the sequence of the other strand.

Question 12

What is the capacity of DNA to store genetic information determined by?

Answer 12

• Number of genes
• Number of base pairs

The diversity of DNA sequences allows for extensive genetic information storage.

Question 13

How many gigabases does the DNA in a human cell contain?

Answer 13

About 3.2 gigabases

This corresponds to approximately 10^9 DNA base pairs.

Question 14

What is the approximate length of DNA contained within a human cell nucleus?

Answer 14

About 2 meters

This DNA is packaged to fit within the microscopic nucleus.

Question 15

True or False: DNA has a limitless capacity for storing genetic information.

Answer 15

True

The diversity of base sequences leads to extensive storage capacity.