test

Question 1

tay sachs

Answer 1

Tay Sachs disease is a rare autosomal recessive progressive neurodegenerative disorder.

death in early childhood. intellectual physical disabilities

disorder of lipid metabolism

caused by a mutation in the HEXA gene the CODES FOR THE ENZYME beta-hexosaminidasem resulting in the accumulation of GM2 gangliosides which destroys neurons

Question 2

y is tay sachs lethal reccesive

Answer 2

ca

Question 3

diabetes 1 and gene therapy

Answer 3

reprogramming other cells to produce insulin.

the gene for insulin is introduced to a vector. the vector is then used to infect the desired cells such as alpha cells in islet of Langerhans

these cells incorporate the new DNA into their nuclear and are able to use protein syntheses to produce insulin

Question 4

cystic fibrosis and y a good candidate

Answer 4

single gene disorder
lung most severely affected organ 
easy to access to provide treatment 
disease slow to progress]
gene therapy to start before significant damage

Question 5

cf and gene therpay

Answer 5

used commo. cold virus as vector to carry normal genes to the CFTR cells in the airways of lungs
gene transfer to small to have any benefits and shirlived

Question 6

chromosomal mutation

y so much worse

Answer 6

in which all or part of a chromosome is affected
as a result of errors in crossing over during meiosis

if mutation remains it is passed on the daughter cells

Question 7

chromosome mutations are potentially more dangerous because

Answer 7

Chromosome mutations are potentially more dangerous than gene mutations because they can be swapped and transferred to that parent’s child. this is if it affects the daughter cells which are gametes.
When a chromosome mutates, whole sets of genes are altered versus 1 gene.

Question 8

cell procceses

Answer 8

meiosis non disjunction: downy syndrome

protien synthesis translocation:

Question 9

germline muation

Answer 9

reproductive cells so passed on to generations
the mutation in the parent is not affected
induced

Question 10

hypothyroidism symptoms are treated with a type of thyroxine (levothyroxine) explain how this made with recombinant DNA [10 marks]

Answer 10

gene that codes for thyroxine is isolated and cut out using a restriction enzyme - causing a staggered cut with sticky ends.

2. plasmid is isolated from bacterial cell and is cut with the same type of restriction enzyme used in step one.
3. human DNA is spliced into the plasmid using DNA ligase enzymes to join the sticky ends.
4. bacterium is treated so it takes up the recombinant plasmid. once successful, the bacterium will multiply so that either the human gene or the product of the gene can be used.