3 - Nucleic acids & RNA

Question 0

Nucleic acids are comprised of a sugar, phospate group and a nitrogen containing base. Name the two groups of bases and their components

Answer 0

Pyrimidines: Uracil (RNA), Thymine, and Cytosine - single ring
Purine: Guanine, Adenine - double ring

Question 1

What are the three substances that comprise a nucleotide?

Answer 1

1) Phosphate group
2) Sugar
3) Nitrogenous containing base

Question 2

What kind of sugar does DNA have? RNA?

Answer 2

DNA - Deoxyribose

RNA - Ribose

Question 3

What is the nemonic to remember the parent of Adenine, Guanine & Cytosine, Uracil, Thymine

Answer 3

Purine is pure like silver = Ag (Adenine & Guanine

Pyrimidine is shaped like a pie and you can CUT it (Cytosine, Uracil, Thymine)

Question 4

In the DNA structure, why doesn’t the pyrimidine’s stick together?

Answer 4

size

Question 5

What type of bond holds the strands of DNA together to form the double helix?

Answer 5

hydrogen bonds

Question 6

Phosphodiester linkage is a __________ reaction

Answer 6

a dehydration reaction

H2O out
forms links in the nucleotide sequence

Question 7

The chain of the carbon on the sugar binds to the phosphate group in a reaction called a phosphodiester linkage. Which pint on the sugar molecule does the link occur

Answer 7

form the 5’ to the 3’

Question 8

The DNA sequence runs in opposite directions - what is this term that describes this structure?

Answer 8

antiparallel helix

Question 9

Which base pairs link up in the DNA sequencing?

Answer 9

A-T - 2 H pairing

G-C 3 H pairing

Question 10

contrast and compare the molecules of DNA & RNA

Answer 10

RNA - sugar is ribose
single strand - can helix with itself + loop
nitrogen containing base Uracil instead of Thymine
RNA the daughter of DNA

DNA - sugar is deoxyribose
double strand
nitrogen containing base Thymine instead of Uracil
DNA the template

Question 11

What are the purposes of RNA?

Answer 11

to process DNA information, DNA’s workhorse to synthesize proteins, defend agains viruses, storage of info, enzymatic

Question 12

What are the three steps to copying a DNA strand?

Answer 12

1 - Unzipping the helix either through heat or an enzyme
2 - polymerization- bonding each side to complementary base pairs = template strand
3 - copy of exact, originals strand zips back up

Question 13

What is holding the antiparallel nucleotide chins together?

Answer 13

hydrogen bonds

Question 14

Can RNA form a helix?

Answer 14

yes, it can form a helix with itself, yet that requires a loop at the top

Question 15

give an example of an enzyme that is used to synthesize proteins

Answer 15

ribozyomes

Question 16

Are double helix strands hydrophilic of hydrophobic?

Answer 16

hydrophilic in general

Question 17

Molecules that have phosphate groups attached are said to be _____________

Answer 17

Phosphorylated
the addition of one or more phosphate group raises the potential energy of the substrate molecules enough to make and otherwise endergonic reaction possible

Question 18

Nucleotides are in RNA are connected to one another in the polynucleotide by:

Answer 18

Covalent bands between sugar and phosphate

Question 19

Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to the DNA molecules treated with these enzymes?

Answer 19

the phosphodiester linkages of the backbone would be broken

Question 20

A certain enzyme can break glycosidic linkages between glucose monomers only if the are in the a form. Which of the following enzyme could this break down?

a) starch, amylopectin & cellulose
b) glycogen & cellulose
c) glycogen, starch & amylopectin
d) cellulose and chitin

Answer 20

D