DNA and RNA

Question 1

name the parts of a DNA nucleotide
3

Answer 1

phosphate
deoxyribose
nitrogenous base

Question 2

what bond is formed between phosphate and deoxyribose

Answer 2

phosphodiester bond

Question 3

what bonds are formed between the nitrogenous bases in a DNA double helix

Answer 3

hydrogen bonds

Question 4

describe the formation of DNA strands in a double helix

Answer 4

antiparallel strands

Question 5

name the monomers of DNA

Answer 5

polynucleotides (joined together using hydrogen bonds)

Question 5

define genome

Answer 5

all of the DNA in an organism

Question 5

name 3 things DNA is that RNA isnt

Answer 5

has deoxyribonucleic acid
G-C A-T
double stranded

Question 6

what percentage of each base is found in humans

Answer 6

cytosine and guanine have 23%
adenine and thymine have 27%

Question 7

describe DNA in eukaryotes

Answer 7

linear
double stranded
found in nucleus
bound to proteins
contains non-coding parts

Question 8

what protein is DNA bound to in eukaryotes

Answer 8

histones

Question 9

describe DNA in prokaryotes

Answer 9

naked
circular
pure function (has no non-coding parts

Question 10

difference in function between DNA and RNA

Answer 10

DNA holds genetic information
RNA transfers genetic information to ribosomes

Question 11

what are ribosomes formed from

Answer 11

rRNA and proteins

Question 12

why did scientists doubt DNA carried the genetic code

Answer 12

because of it’d relative simplicity

Question 13

define semi-conservative replication

Answer 13

making 2 molecules of DNA that are identical using one original strand of DNA as the termplate

Question 14

what are the 4 sections of the cellcycle

Answer 14

growth
DNA synthesis
growth + preparation for mitosis
mitosis

Question 14

what enzyme unzips DNA for semi-conservative replication and how does it work

Answer 14

DNA helicase
it breaks hydrogen bonds between nitrogenous bases

Question 15

what are the split strands of DNA called

Answer 15

parental strands

Question 16

how do bases join the parental strands during complimentary based pairing

Answer 16

free floating nucleotides in the nucleus are attracted to these parental strands of DNA

Question 17

what does DNA polymerase do in semi conservative replication

Answer 17

reads nucleotides and enables them to join new strand as condensation reactions occur to form phosphodiester bonds

Question 18

what direction does DNA polymerase work in and what does that mean

Answer 18

works in 5’ - 3’ direction
DNA polymerase can only bind to 3’ end so will only go in one direction
the anti-parallel strands mean the enzyme goes in opposite directions for each strand

Question 19

who made the proof for semi-conservative replication

Answer 19

Meselson and Stahl

Question 20

what was Meselson and Stahl’s proof

Answer 20

labelled the DNA of bacteria across generations using isotopes of nitrogen. From the patterns of DNA labelling they saw,
they confirmed that DNA is replicated semi-conservatively.

Question 21

how many hydrogen bonds are there between
adenine and thymine
cytosine and guanine

Answer 21

A-T =3
C-G=2

Question 22

what happens before mRNA is sent out of the nucleus

Answer 22

pre-mRNA is spliced

Question 23

in translation, what energy is used to form peptide bonds

Answer 23

ATP

Question 24

name the bases

Answer 24

adenine thymine (only DNA) Guanine Cytosine Uracil (only RNA)

Question 25

how is a phosphodiester bond formed

Answer 25

a condensation reaction between two adjacent nucleotides

Question 26

describe a DNA molecule

Answer 26

double helix two polynucleotide chains held together by hydrogen bonds between complimentary base pairs

Question 27

describe an RNA molecule

Answer 27

relatively short polynucleotide chain

Question 28

in prokaryotic cells, what form is dna

Answer 28

short, circular, not associated with proteins

Question 29

what is the name of the protein associated with DNA

Answer 29

histones

Question 30

in eukaryotic cells, what is the form of dna

Answer 30

long linear associated with proteins DNA molecule and proteins form a chromosome

Question 31

what are the 2 things a base sequence of dna codes for

Answer 31

amino acid sequence of a polypeptide a functional RNA

Question 31

in eukaryotic cells, what else contains DNA how does this dna differ from the dna in the nucleus

Answer 31

mitochondria chloroplasts it is short, circular and not associated with proteins

Question 32

what is teh fixed position a gene occupies on a particular DNA molecule

Answer 32

a locus

Question 33

give 3 words to describe the genetic code

Answer 33

degenerate non-overlapping universal

Question 34

what does degenerate mean

Answer 34

multiple codons can code for the same amino acid

Question 35

what does universal mean

Answer 35

in all organisms on earth, the same codons code for the same amino acids

Question 36

what does non-overlapping mean

Answer 36

each base can only be in one codon/tripet