M5: DNA Structure

Question 1

What are the complementary bases?

Answer 1

adenine- thymine
guanine - cytosine

Question 2

What is a nucleotide composed of?

Answer 2

sugar molecule (deoxyribose), phosphate, and one nitrogenous base

Question 3

Who discovered nucleotides?

Answer 3

Watson and Crick

Question 4

What does the waston and creek model display?

Answer 4

Large linear molecule arranged as a double helix with 4 nitrogenous bases held together by hydrogen bonds

Question 5

What is DNA?

Answer 5

Deoxyribonucleic acid > double stranded helix structure with repeating series of nucleotide units formed from nitrogenous bases and a sugar-phosphate backbone

Question 6

What is RNA?

Answer 6

Ribonucleic acid that is single stranded and has 4 nitrogenous bases (except uracil instead of thymine) and has three main forms - mRNA, rRNA, tRNA

Question 7

What do hydrogen bonds do?

Answer 7

hold polynucleotides together, with 2 bonds for A-T and 3 for C-G and add nucleotides to the 3’ end of the DNA

Question 8

How does DNA work in prokaryotes?

Answer 8

• double stranded and have circular chromosomes
• in plasmids or loops
• no histone proteins

Question 9

How does DNA work in eukaryotes?

Answer 9

• chromosomes contain a single DNA molecule and have histone proteins
• linear chromosomes with the constant number and condensed to divide