UNIT 1 TEST

Question 1

What is differentiation?

Answer 1

process that cells become specialised for a particular function and can’t change into different cell types

Question 2

What are embryonic stem cells involved in

Answer 2

growth repair and renewal of cells found in the tissue

Question 3

Germline cells

Answer 3

If mutation occurs then mutation is PASSED onto the offspring

Question 4

Somatic cells

Answer 4

If mutation occurs its NOT PASSED onto the offspring

Question 5

Therapeutic use of stem cells

Answer 5

bone marrow transplant

skin grafts

Question 6

what is cancer

Answer 6

uncontrolled growth of cells

Question 7

why do cancer cells divide uncontrollably

Answer 7

• dont respond to the usual regulatory signals and chemical messengers inside and outside the cell to produce a mass of abnormal cells
• if cancer cells fail to attach to each other, they can spread throughout the body to form secondary tumours.

Question 8

what is a tumour

Answer 8

abnormal cells produced by uncontrollable cell division

Question 9

what forms DNA nucleotides

Answer 9

• phosphate
• deoxyribose sugar
• base

Question 10

whats the backbone called

Answer 10

sugar phosphate backbone

Question 11

prevent tangling in dna

Answer 11

molecules of the DNA are tightly coiled around proteins

Question 12

what does DNA polymerase do

Answer 12

adds complementary DNA nucleotides to the 3’ end

Question 13

what does ligase do

Answer 13

enzyme that joins DNA fragments together

Question 14

what is the structure of RNA

Answer 14

• phosphate
• ribose sugar
• base

Question 15

differences between DNA and RNA

Answer 15

• rna is single stranded and DNA is double stranded
• RNA contains uracil and DNA contains Thymine
• RNA contains ribose sugar and DNA contains deoxyribose sugar

Question 16

Transcription

Answer 16

mRNA carries a copy of the DNA code out the nucleus to the ribosome

Question 17

tRNA

Answer 17

bring specific amino acids to the ribosome where the mRNA and the genetic information is translated into a protein

Question 18

what enzyme is responsible for transcription

Answer 18

RNA polymerase

Question 19

what is a mutation

Answer 19

change to the genetic structure of an organism

Question 20

missense mutation

Answer 20

altered codon for amino acid still makes sense but not the original sense.

Question 21

Nonsense mutation

Answer 21

a codon used to code for an amino acid is exchanged for one that acts as a premature stop codon. it causes protein synthesis to be halted prematurely and results in a polypeptide chain shorter than normal and unable to function

Question 22

splice site mutation

Answer 22

if one or more introns have been retained by modified mRNA, they may in turn be translated into an altered protein that doesn’t function properly

Question 23

frameshift

Answer 23

every codon after the site of mutation to be altered. altered protein will not be able to function

Question 24

PCR

Answer 24

1- dna strands separate
2-primers bind to the DNA strands
3- DNA polymerase builds nucleotides into the DNA strands

Question 25

what does amplification of DNA mean

Answer 25

process of taking a tiny sample of DNA and producing vast numbers of copies of it

Question 26

enzyme involved in PCR

Answer 26

Taq polymerase

Question 27

what is a DNA probe

Answer 27

detect the presence of a specific sequence of nucleotide and they have a fluorescent label so they can be detected easily

Question 28

what is anabolic pathway

Answer 28

building up complex molecules and REQUIRE energy

Question 29

what is catabolic pathway

Answer 29

breakdown of molecules. they RELEASE energy

Question 30

what factors can affect enzyme activity

Answer 30

• ph
• temperature
• inhibitors

Question 31

how does competitive inhibitor work

Answer 31

bind with the active site and block it from the substrate . it can be reversed by adding more substrate

Question 32

how does non competitive inhibitor work

Answer 32

bind to the enzyme NOT the active site. they change the shape of the active site so the substrate no longer fits, it can’t bind

Question 33

what is phosphorylation

Answer 33

phosphate groups added to a molecule

Question 34

where does glycolysis take place

Answer 34

cytoplasm

Question 35

state what glycolysis is

Answer 35

glucose is broken down to pyruvate

doesnt require energy

Question 36

energy investment stage

Answer 36

2 ATP are used up

Question 37

energy pay off stage

Answer 37

4 ATP are produced

Question 38

what enzyme controls the release of hydrogen ions from substrate

Answer 38

dehydrogenase

Question 39

where does the citric acid cycle take place

Answer 39

central matrix of the mitochondria

Question 40

how is citrate formed

Answer 40

acetyl coenzyme A combines with oxalocetate to form citrate

Question 41

what is formed during citric acid cycle

Answer 41

ATP and Carbon dioxide

Question 42

where does the electron transport chain found

Answer 42

inner membrane of the mitochondria

Question 43

what is the final hydrogen acceptor and what substrate does it form when combined with hydrogen

Answer 43

oxygen which combines with hydrogen ions and electrons to form water

Question 44

what inhibits phosphofruitokinase?

Answer 44

high levels of ATP and citric acid

Question 45

what is type of activity is slow twice muscle fibre good for

Answer 45

long distance running

Question 46

what type of activity is fast twitch muscle fibre good for

Answer 46

weighlifting

sprinting