replication and protein synthesis

Question 1

example of a nucleotide not DNA or RNA

Answer 1

ATP

Question 2

ATP strucure

Answer 2

ribose adenine and 3 phosphates

Question 3

DNA structure

Answer 3

sugar base and phosphate

Question 4

features of DNA molecules

Answer 4

2 strands antiparallel to eachother
double helix
each chain has sugar phosphate backbone with bases at right angles
each chain is a right handed helix

Question 5

how many rings in purines

Answer 5

2

Question 6

how many rings in pyrimidines

Answer 6

1

Question 7

which bases are purines

Answer 7

adenine and guanine

Question 8

which bases are pyrimidines

Answer 8

cytosine thymine and uracil

Question 9

which bases make 3 hydrogen bonds

Answer 9

Cytosine and guanine (CGP=CG3)

Question 10

which bases make 2 hydrogen bonds

Answer 10

adenine thymine and uracil

Question 11

true or false purines pairs with a purine

Answer 11

false purines always pair with pyrimidines (think about which one shave 2 vs 3 hydrogen bonds)

Question 12

which enzymes breaks complementary hydrogen bonds in the first step of DNA replication

Answer 12

DNA helicase

Question 13

which way does leading strand unwind

Answer 13

5’ to 3’

Question 14

which way does DNA polymerase work

Answer 14

5’ to 3’

Question 15

how does DNA polymerase work

Answer 15

attaches to single strand and adds one new nucleotide at a time

Question 16

how does DNA polymerase work on laggin strand

Answer 16

works in opposite direction to unwinding. Copies unwound pieces then goes back to copy next piece creating small fragments called Okazaki fragments

Question 17

what enzyme sticks nucleotides together and how

Answer 17

DNA ligase makes covalent phosphodiester bonds between nucleotides

Question 18

how are strands held together before DNA ligase

Answer 18

hydrogen binds between complementary bases

Question 19

semi conservative replication

Answer 19

DNA molecule is copied to form 2 identical molecules each containing one strand from the original molecule and one newly synthesised strand

Question 20

how many amino acids are there

Answer 20

20

Question 21

how many possible combinations of 3 bases are there

Answer 21

4^3 64

Question 22

different codons can code for the same amino acid what is this called

Answer 22

degenerate/redundant code

Question 23

first step of protein synthesis

Answer 23

transcription (you must write a speech before you say it)

Question 24

transcription takes place in the

Answer 24

nucleus

Question 25

what enzyme is used in transcription

Answer 25

RNA polymerase

Question 26

how does transcription work

Answer 26

RNA polymerase attaches to beginning of gene, it unwinds the DNA of the gene DNA helicase unzips the DNA complementary RNA copy of the template strand is made from free nucleotides and hydrogen bond RNA polymerase attaches them to each other with phosphodiester bond and hydrogen bond is broken mRNA leaves through nuclear pore in nuclear envelope

Question 27

another name for template strand

Answer 27

transcribed strand

Question 28

which direction does RNA polymerase work in

Answer 28

5' to 3'

Question 29

do RNA and DNA polymerase work in the same direction

Answer 29

yes 5' to 3'

Question 30

what step is in between transcription and translation

Answer 30

modification/ splicing

Question 31

how is mRNA modified

Answer 31

RNA splicing. Removing introns from primary transcript and exons are joined together

Question 32

translation

Answer 32

tRNA transfers amino acids to the ribosome and mRNA is converted/translated into a polypeptide chain

Question 33

where does translation take place

Answer 33

ribosome

Question 34

what are ribosomes made out of

Answer 34

small and large subunit made of rRNA and protein

Question 35

when an mRNA molecule arrives at a ribosome where doe sit enter

Answer 35

groove between 2 subunits

Question 36

how many tRNA can fit on ribosome at any time

Answer 36

2

Question 37

what bond is formed between amino acids

Answer 37

peptide bond (before the anticodon and codon were hydrogen bonded)

Question 38

2 types of mutations

Answer 38

gene and chromosome

Question 39

chromosome mutation

Answer 39

a random and unpredictable change in the structure or number of chromosomes in a cell

Question 40

gene mutation

Answer 40

change in base sequence in part of a DNA molecule

Question 41

substitution

Answer 41

base replaced by a different base

Question 42

deletion

Answer 42

base is lost and not replaced

Question 43

insertion

Answer 43

base is added

Question 44

deletion and insertion are

Answer 44

frame shift mutations- incorrect reading of the sequence of triplets in the genetic code due to a frame shift in the reading frame