BiotechnologyIB MYP Biology: Topic test

20 questions, 54 marks

IB MYP Biology

Biotechnology topic test

Total 54 marks

Name

Class

Date

1
Some children do not make enough growth hormone and need regular injections of it. The hormone is now made by genetically modified bacteria. Scientists identified the human gene for growth hormone, cut it out of human DNA and inserted it into a bacterial plasmid, which was then put into bacteria.
(a)
What is the role of the plasmid in this process?
[1 mark]
ATo cut the gene out of the human DNA
BTo carry the gene into the bacterial cell
CTo digest the hormone after it is made
DTo supply the bacteria with energy
(b)
What must the bacteria do with the gene for the hormone to be made?
[1 mark]
ARemove it from the plasmid
BCopy it once and then stop dividing
CUse it to make a cell wall
DExpress it, using it to make the hormone protein
(c)
Explain why bacteria are used to make the hormone in large amounts.
[2 marks]
Total for question 1: 4 marks
2
A poultry breeder in Thailand wants hens that lay more eggs. In each generation she breeds only from the hens that laid the most eggs, mating them with cockerels whose mothers were also good layers. After 20 generations the flock lays an average of 290 eggs a year, compared with 180 at the start. However, the birds are now very similar genetically, and last year one disease killed many of them.
(a)
What is the first step in this selective breeding?
[1 mark]
AChoosing parent hens that show the characteristic wanted
BExposing the hens to radiation to cause mutations
CCutting the egg-laying gene out of the DNA of a hen
DCloning the best hen to make identical offspring
(b)
Which problem is most likely to be caused by breeding only from a few similar hens?
[1 mark]
AThe flock gains more variation, so a disease affects fewer birds
BThe offspring become unable to reproduce
CReduced genetic variation, so a single disease can affect all of the birds
DThe hens change their alleles to match their surroundings during their lifetime
(c)
Explain how selective breeding differs from natural selection.
[2 marks]
Total for question 2: 4 marks
3
Students at a school in Nepal want to find out how temperature affects the rate at which biogas forms from cow dung. Biogas, a mixture of methane and carbon dioxide, is made when bacteria break down organic waste without oxygen, and many farms in Nepal use small digesters to make biogas for cooking. The students plan to put mixtures of cow dung and water in sealed bottles at different temperatures and to collect the gas that forms.
(a)
State a testable hypothesis about the effect of temperature on the volume of biogas collected, with a scientific reason, and identify the independent variable.
[3 marks]
(b)
Outline how the students could collect reliable data safely. Identify the dependent variable, one control variable, one safety precaution and one way of making the results reliable.
[4 marks]
Total for question 3: 7 marks
4
Sickle cell disease is a serious inherited disorder caused by a faulty allele of one gene, and it is common in parts of West Africa. Scientists can sequence a person's genome to find the faulty allele, and experimental gene therapy inserts a healthy copy of the gene into a patient's bone-marrow cells. A health ministry in a West African country has money for only one of two programmes. Programme 1 gives gene therapy, which costs a very large amount per patient, to about 200 patients. Programme 2 spends the same money on genetic testing, counselling and standard care for many thousands of people.
(a)
Explain how genome sequencing, genetic testing and gene therapy could each help families affected by this disease.
[6 marks]
(b)
Evaluate which of the two programmes the ministry should fund.
[6 marks]
Total for question 4: 12 marks
5
Most bananas sold around the world come from plantations in countries such as Ecuador, where the plants are grown by tissue culture. Small pieces of tissue from one chosen banana plant are grown on sterile jelly containing nutrients and hormones, and the new plantlets are then planted in fields. A fungal disease called Panama disease is spreading in some banana-growing regions.
(a)
How do the plantlets compare with the original plant?
[1 mark]
AThey have a mixture of genes from two parents
BThey have half of the genes of the original plant
CThey are genetically identical to the original plant
DThey have different genes because the jelly causes changes
(b)
Why could a fungal disease be a serious problem for a plantation of cloned banana plants?
[1 mark]
AThe plants have the same genes, so one disease could affect all of them
BCloned plants grow too slowly to recover from disease
CCloned plants have no genes for resistance at all
DTissue culture makes the plants more variable
(c)
Explain why tissue culture is useful for growing large numbers of banana plants.
[2 marks]
Total for question 5: 4 marks
6
A factory in Japan grows yeast in a large stainless steel fermenter containing sugar solution, to make ethanol for use as a biofuel. The fermenter is sealed so that no air enters, the contents are stirred, and the temperature is kept at about 35 °C. Fermentation releases heat, so the fermenter has a cooling jacket.
(a)
Why does the fermenter need a cooling jacket?
[1 mark]
ATo stop the yeast from respiring
BTo freeze the sugar solution
CTo make the yeast produce oxygen
DTo remove the heat released and keep the temperature at which the yeast enzymes work best
(b)
Which products does the yeast make in the sealed fermenter?
[1 mark]
ALactic acid and carbon dioxide
BEthanol and carbon dioxide
CEthanol and oxygen
DWater and carbon dioxide
(c)
Explain why the fermenter and the sugar solution are sterilised before the yeast is added.
[2 marks]
Total for question 6: 4 marks
7
Breeders in Spain selected tomato plants for large fruit over five generations. In each generation they bred only from the plants with the biggest fruit. The mean fruit mass was 60 g, 75 g, 95 g, 110 g, 118 g and 120 g in generations 0 to 5. A taste panel scored the flavour out of 10, giving mean scores of 8, 7, 6, 5, 4 and 4 for generations 0 to 5.
(a)
Describe the trend in mean fruit mass and calculate the mean increase in fruit mass per generation between generation 0 and generation 5.
[3 marks]
(b)
The breeders hypothesised that selecting the largest fruit would give bigger tomatoes with the same flavour. Evaluate this hypothesis using the data.
[4 marks]
Total for question 7: 7 marks
8
Millions of people are blind because the cornea, the clear front part of the eye, is damaged, and there are not enough donated corneas for transplants. Researchers have used a bioprinter to make a small piece of cornea-like tissue. The printer deposits a gel containing living stem cells, layer by layer, following a computer design. The printed tissue has not yet been tested in patients. A government can spend its health research budget either on bioprinting research or on campaigns to persuade more people to donate their corneas.
(a)
Explain how a bioprinter makes human tissue, how this could help patients who need transplants, and why printing whole organs is not yet possible.
[6 marks]
(b)
Evaluate whether the government should spend the money on bioprinting research rather than on donor campaigns.
[6 marks]
Total for question 8: 12 marks

End of questions

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).