Moulsham High School 1 Level 7 Biology Questions 1. The graph below shows how a population of fish in a lake changed over a period of time. (a) In which time interval, A, B, C, D or E, did the population of fish increase most quickly? .............. How can you tell this from the graph? ...................................................................................................................... ...................................................................................................................... 1 mark (b) Which part of the graph shows when the fish began to compete with each other for food? Give the letter. .............. How can you tell this from the graph? ...................................................................................................................... ...................................................................................................................... 1 mark (c) What does part D of the graph show about the birth rate and the death rate of the fish? ...................................................................................................................... How can you tell this from the graph? ...................................................................................................................... ...................................................................................................................... 1 mark
22
Embed
Level 7 Biology Questions - Moulsham High School 7 Biology Questions.pdf · Moulsham High School 1 Level 7 Biology Questions 1. The graph below shows how a population of fish in a
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Moulsham High School 1
Level 7 Biology Questions
1. The graph below shows how a population of fish in a lake changed over a period of time.
(a) In which time interval, A, B, C, D or E, did the population of fish increase most quickly?
2. Andy investigated the digestion of a protein called gelatin. He used an enzyme called pepsin from the human stomach, and three cubes of gelatin each 1 cm3. He set up the experiment shown below and put the test-tubes in a water-bath at 37°C. He measured the time for the digestion of the gelatin.
(a) Why did Andy choose a temperature of 37°C for t he water-bath?
4. Read the magazine cutting about research into heart disease.
More heart disease in older women. Heart disease amongst British women in the 60-79 age group is more common than previous research suggested. A recent study of 4,286 British women in that age group indicated that one in five showed signs of heart disease.
Moulsham High School 6
(a) Why can the results of this research not be used to draw any conclusions about
(b) In 1970 the average concentration of DDT in the tissues of sea lions in California was 760 parts per million. Nearly half the sea lion pups born in that year died because of high levels of DDT in their tissues.
How does DDT get from the body of a mother sea lion into the body of her pup:
Scientists at the University of Leeds have found a way to modify the genes of flowering plants. They claim that flowers from modified plants remain fresh in a vase of water for up to six months longer than flowers from unmodified plants.
Plan an investigation you could carry out in the school laboratory to test the claim that flowers from modified plants last for much longer than flowers from unmodified plants.
You will be provided with flowers from modified plants and from unmodified plants.
Moulsham High School 12
In your plan give:
• the one factor you will change as you carry out your investigation; (This is the independent variable.)
• the factor you will measure; (This is the dependent variable.)
• one of the factors you should control to ensure a fair test; • the time scale for the investigation.
8. The drawings show Sofia taking part in four different sports.
The table below shows the average energy needed for each sport for one hour.
sport average energy need for one hour (kJ)
bowling 1030
tennis 1760
football 2260
running 3700
(a) (i) Sofia plays football for two hours each week. She also goes bowling for two hours each week. Explain why Sofia uses up her food reserves more quickly when playing football than when bowling.
(b) Some athletes take glucose tablets before a 100 metre race. They can also obtain glucose from starch in their diet. A starch molecule is made up of many glucose molecules joined together as shown below.
part of a molecule of starch
In the digestive system, starch is broken down into glucose:
molecules of glucose
An athlete can obtain energy more quickly by eating glucose rather than starch. Explain why.
9. Cholera is a disease caused by bacteria. These bacteria produce a poison. The poison prevents the large intestine from absorbing water from the food passing through it. People with cholera can lose more than a litre of water per hour.
(c) The cholera poison makes the skin permeable. A new method of vaccinating against cholera is to put a small amount of the poison, mixed with other vaccines, on a plaster. The plaster is left on the skin for a day. The vaccines pass through the skin and the person becomes immune to cholera and to other diseases.
(i) Why should only a tiny amount of the poison be used?
(b) These days there are some zebras that still show some quagga features. Scientists are using zebras to try to produce quaggas by selective breeding. Describe the steps in this selective breeding process.
Use the data in the scatter graphs to show whether each of the conclusions below is true, false or you cannot tell.
conclusions true or false or cannot tell
Graph C shows that the shortest pupil has the smallest hand span. ........................................
Graph B shows the strongest correlation between two variables. ........................................
Graph A looks similar to graph C because of the high correlation of arm span to hand span. ........................................
Boys are generally taller than girls. ........................................
2 marks
Maximum 4 marks
Moulsham High School 21
13. Almost 200 years ago, an important investigation into plant growth was carried out.
George Sinclair, the Duke of Bedford’s head gardener, planted seeds in 242 plots of land, each four feet square.
Charles Darwin concluded from this investigation:
If a plot of ground is sown with one species of grass and a similar plot is sown with several different species of grass, the second plot will produce a greater number of plants and a greater mass of plant material.
(a) Give one feature of the plots that was controlled in Sinclair’s investigation.