Biology Unit

The two strands of a DNA molecule are held together by __________.

• ionic bonds

• hydrogen bonds

• peptide bonds

• covalent bonds

DNA replication is said to be semiconservative, meaning that

• it doesn’t use very much energy when replicating

• it contains one original and one new strand

• it is bacteria resistant

• it occurs in opposite directions

Which of the following is not part of a nucleotide in a DNA molecule?

• a base

• a sugar

• a phosphate group

• three phosphate groups

Hershey and Chase chose to use bacteriophages in their experiments because these viruses __________.

• will not grow in radioactive culture

• can be seen with a light microscope

• can infect only bacteria, not humans

• contain little more than DNA and protein

As a result of the Hershey and Chase experiments, scientists believe that _________.

• the ‘transforming principle’ is DNA

• radioactive isotopes can be used safely

• viruses use bacterial DNA to reproduce

• bacteriophages can be grown in culture media

The four types of nucleotides that make up DNA are named by their __________.

• Hydrogen bonds

• Phosphate groups

• Ring-shaped sugars

• Nitrogen-containing bases

Which of the following answers correctly pairs the nitrogenous bases in DNA?

• Adenine = Thymine & Cytosine = Guanine

• Adenine = Uracil & Cytoplasm = Guanine

• Adenine = Cytosine & Uracil = Guanine

• Adenine = Cytosine & Thymine = Guanine

In a DNA molecule, the amount of Adenine is always equal to the amount of:

• Cytosine.

• Guanine.

• Thymine.

• Uracil.

Tags

NGSS.HS-LS1-1

In a DNA molecule, the nitrogenous bases are joined by which type of bond?

• Strong covalent bonds

• Weak covalent bonds

• Strong hydrogen bonds

• Weak hydrogen bonds

Tags

NGSS.HS-LS1-1

Which two scientists are given the credit for discovering the structure of DNA?

• Watson and Crick

• Chargoff and Franklin

• Wilkins and Crick

• Crick and Franklin