Topic 4A- DNA,RNA and Protein Synthesis

Question 1

gene

Answer 1

section of DNA, codes for the sequence of amino acids that forms a particular polypeptide (primary structure)

Question 2

in eukaryotic cells, where is DNA found

Answer 2

in a nucleolus within the nucleus

Question 3

in eukaryotic cells, what if the shape of the DNA

Answer 3

linear strands

Question 4

in eukaryotic cells, what type are the proteins other DNA contains

Answer 4

histone proteins

Question 5

in prokaryotic cells, where is the DNA found

Answer 5

free floating in cytoplasm

Question 6

in prokaryotic cells, what shape is the DNA

Answer 6

circular loop

Question 7

does prokaryotic cells have histone proteins

Answer 7

no

Question 8

in some prokaryotic cells, what other structure of DNA do they contain

Answer 8

plasmid

Question 9

is the DNA structure always the same in different organisms

Answer 9

yes, nucleotides are always the same
means they are known as universal

Question 10

how many naturally occurring aminos acids are there

Answer 10

20

Question 11

how many nucleotides code 1 amino acid

Answer 11

3

Question 12

why aren’t nucleotides in pairs

Answer 12

because there wouldn’t be enough combinations of nucleotides to make up the amino acids

Question 13

what is it called when the same n-bases code for the same amino acid

Answer 13

degenerate

Question 14

what does non-over lapping mean

Answer 14

that only each base is read once

Question 15

what is at the end of a gene before a new gene

Answer 15

a STOP triplet

Question 16

does a STOP triplet code for anything

Answer 16

no

Question 17

does DNA have non-coding proteins, if so why

Answer 17

yes they do, we don’t know why

Question 18

what is protein synthesis (short answer)

Answer 18

making proteins

Question 19

what are the 3 types of RNA

Answer 19

mRNA, tRNA and ribosomal RNA

Question 20

what does DNA contain

Answer 20

the sequence of nucleotides that code for all proteins

Question 21

what are the two stages of protein synthesis

Answer 21

transcription and translation

Question 22

simplify what transcription is

Answer 22

making a copy of the target gene
-copys
-cuts out unwanted
-sticks extrons back together

Question 23

simplify what translation is

Answer 23

reading the information from the mRNA, and reading it with the appropriate amino acids

Question 24

what does DNA helicase do

Answer 24

unwinds the DNA, breaking the hydrogen bonds

Question 25

what are the two stands of DNA called when unravelled

Answer 25

sense strand and antisense strand

Question 26

what is the promotor region

Answer 26

marks the start of a gene

Question 27

what does RNA polymerase do

Answer 27

moves along antisense strand forming phosphodiester bonds between complementary RNA nucleotides

Question 28

when doe RNA polymerase stop and release off the DNA strand

Answer 28

reaches a stop triplet at the end of a gene

Question 29

what is an intron

Answer 29

non-coding sections of RNA

Question 30

what is splicing

Answer 30

an enzyme cutting out the introns and sticking the exons back together

Question 31

once spliced, where does the mRNA go

Answer 31

exits the nucleus out of pores and goes into the cytoplasm to ribosomes

Question 32

how is the mRNA protected to travel through the cytoplasm

Answer 32

a polyadenine tail and a cap on the other end

Question 33

what is the structure of tRNA

Answer 33

a single stranded piece of RNA, folded into a ‘clover leaf’ shape

Question 34

what holds tRNA in its shape

Answer 34

hydrogen bonds

Question 35

what is on tRNA that is complementary for a specific amino acid it carries

Answer 35

anticodon

Question 36

what is formed between the amino acids once read i the ribosome

Answer 36

peptide bond