dddna

Question 1

what is a histone

Answer 1

the protein that dna is wrapped around

Question 2

do prokaryotic cells have histone complexes

Answer 2

no

Question 3

when dna is wrapped a histone what is formed

Answer 3

chromosome

Question 4

what is an allele

Answer 4

different versions of the same gene

Question 5

what is the strcuture of dna

Answer 5

a double helix with strands bonded by hydrogen bonds between nirogenous bases and phosphodiester bonds between nucleotides

Question 6

define genome

Answer 6

the complete set of genes in a cell including those in mitochondria and chloroplasts

Question 7

define proteome

Answer 7

the full range of proteins produced by the genome

Question 8

what is mRNA

Answer 8

a long strand that is arranged into a single helix

Question 9

what is the function of mRNA

Answer 9

acts as a template for DNA in protein synthesis

Question 10

what is a codon

Answer 10

three bases that are complementary to a triplet in DNA

Question 11

what will a sequence of codon do

Answer 11

determine the amino acid sequence of a specific polypeptide that will be made

Question 12

what is tRNA’s structure

Answer 12

a single stranded chain folded into a clover leaf shape, with one end of the chain extending over the other - at this part of the molecule is where the AA can easily attach

Question 13

where is an anticodon located

Answer 13

opposite end of a tRNA molecule

Question 14

define degenerate code

Answer 14

several codons that code for one amino acid

Question 15

what is an anticodon

Answer 15

three more nitrogenous bases that are complementary to the codon

Question 16

what is non-overlapping code

Answer 16

each codon only codes for one amino acid

Question 17

what is universal code

Answer 17

genetic code is the same inall living organisms

Question 18

derscribe the stages of transcription

Answer 18

DNA helicase attaches and breaks the hydrogen bonds to expose the bases.
- RNA polymerase attaches
- RNA polymerase works in the 5’3 direction
- rna polymerase will bind complementary base pairs together until a stop codon si reached - this creates pre - mrna
it needs to be spliced to remove introns

DNA polymerase will join adjacent bases behind it.
mrna can now leave the nucleus

Question 19

why do prokaryotes not need ;to be spliced

Answer 19

they dont have introns

Question 20

describe translation

Answer 20

a ribosome becomes attached to the start codon
- the trna molecule that is complementary to the codon brings an amino acid with its anticodon
-two amino acids are able to fit at any one time - they will join by a peptide bond
this repeats until stop codon is reached and a primary protein is acheieve