DNA And RNA

Question 1

DNA

Answer 1

Chemical that determines inherited characteristics and contains vast amounts of information in the form of the genetic code

Question 2

RNA

Answer 2

Help convert genetic code of DNA into functional protein

Question 3

DNA nucleotide

Answer 3

Phosphate group backbone
Pentose (deoxyribose)
Nitrogenous base
(Adenine, Guanine, Cytosine, Thymine)

Question 4

RNA nucleotide

Answer 4

Phosphate group backbone
Pentose (ribose)
Nitrogenous base
(Adenine, Guanine, Cytosine, Uracil)

Question 5

What reaction joins nucleotides?

Answer 5

Condensation

Question 6

What bond is formed between nucleotides?

Answer 6

Phosphodiester bonds

Question 7

What bonds keep 2 nucleotide chains together?

Answer 7

Hydrogen bonds

Question 8

Structure of DNA

Answer 8

Double helix, 2 strands of polynucleotides, run anti parallel to each other, twisted into coil

Question 9

Bonds in adenine, thymine

Answer 9

2 hydrogen bonds

Question 10

Bonds in cytosine, guanine molecules

Answer 10

3 hydrogen bonds

Question 11

What type of molecule is a thymine, cytosine molecule?

Answer 11

Pyramidine molecule (ring)

Question 12

What type of molecule is adenine and guanine molecule?

Answer 12

Purine molecules (double rings)

Question 13

Stability of DNA

Answer 13

Stable, phosphodiester bonds are strong covalent bonds

Hydrogen bonds are strong when there are many

Question 14

Adaptations of DNA

Answer 14

Stable, passes onto next gen without change
2 strands joined with hydrogen bonds, allow them to be easily separated during DNA replication and protein synthesis
Base pairs in helical cylinder, genetic info protected from outside chemical and physical force

Question 15

Discovery of DNA

Answer 15

Watson and Crick, Cavendish lab in Uni of Cambridge
Completed with Franklin, Pauling,Wilkins
X-rays produced images of DNA
Chargaff’s rule, DNA should have 1:1 ratio of pyramidine, purine bases
Watson led genome project

Question 16

Comparison between eukaryotic and prokaryotic chromosomes

Answer 16

DNA, v long, linear, associated with histones
DNA, short, circular, not associated with proteins
Histones allow more folding

Question 17

DNA and chromosomes

Answer 17

Nucleosome, 8 histones with DNA wrapped around twice

Chromosome=DNA molecule and histones

Question 18

Mitochondrial and chloroplast DNA

Answer 18

Mitochondrial DNA, similar to prokaryotic DNA
Chloroplasts DNA, similar to prokaryotic DNA
Not associated with proteins

Question 19

Genes

Answer 19

Base seq of DNA, codes for amino acid seq of polypeptide

Question 20

Locus

Answer 20

Gene occupies fixed position on chromosome

Question 21

Triplet code

Answer 21

Seq of 3 base code for 1 amino acid

Question 22

Exons

Answer 22

Code for animo acid seq

Question 23

Introns

Answer 23

Separate exons by non coding regions

Question 24

mRNA

Answer 24

Bases complementary to 1 of the DNA strands
Formed in nucleus, moves to ribosomes
Acts as a template upon which proteins are made
Easily broken down, only exists when needed, less wasteful

Question 25

tRNA

Answer 25

80 nucleotides long
Clover leaf structure
Shape held together by hydrogen bonds
2 distinctive ends
1 end, amino acid attachment site, other site, anticodon, complementary to mRNA codon
Chemically more stable than mRNA
Only produced when necessary

Question 26

Universal

Answer 26

Same codon codes for same amino acid in all organisms

Question 27

Non overlapping

Answer 27

Each base sequence is only read once

Question 28

Degenerate

Answer 28

Most amino acids have more than 1 codon