year 11 biology time: 2 hours...page 2 of 13 biology – year 11 – track 3 – 2018 section a:...
TRANSCRIPT
DEPARTMENT FOR CURRICULUM,
RESEARCH, INNOVATION AND LIFELONG LEARNING
Directorate for Learning and Assessment Programmes
Educational Assessment Unit
Annual Examinations for Secondary Schools 2018
YEAR 11 BIOLOGY TIME: 2 hours
Name: _____________________________________ Class: _______________
Question
No.
Section A Section B
1
2
3
4
5
6 7
1
2
3
4
5
Max.
mark
7 9 6 5 9 6 13 15 15 15 15 15
Actual
mark
TOTAL
MARK
Track 3
Page 2 of 13 Biology – Year 11 – Track 3 – 2018
SECTION A: Answer ALL the following questions. This section carries 55
marks.
1. Figure 1.1 shows the set-up for an investigation using a partially peeled, uncooked potato.
Figure 1.1
A student put concentrated sugar solution in the scooped out part of the potato and water at the base of the potato. This set up was left for 24 hours.
Figure 1.2 shows three different results.
Figure 1.2
a. List the letter that shows the correct result of this investigation. (1 mark)
____________________________________________________________
b. Explain why the result listed above is the correct one. (2 marks)
____________________________________________________________
____________________________________________________________
c. Name the process that occurs in the investigation. (1 mark)
____________________________________________________________
d. Explain why the skin is peeled off at the base of the potato. (1 mark)
____________________________________________________________
e. When onion epidermal cells are put in the concentrated sugar solution, these
cells become plasmolysed. Explain. (2 marks)
____________________________________________________________
Total 7 marks
Biology – Year 11 – Track 3 – 2018 Page 3 of 13
2. Proteins are defined as the building blocks of cells. Proteins may have
different molecular structures giving each type a specific function. Specific proteins are produced by specialised cells.
a. i. Name the structural components (monomers) of a protein molecule.
(1 mark)
____________________________________________________________
ii. Explain how proteins are different from each other. (2 marks)
____________________________________________________________
____________________________________________________________
b. Complete the table below to include the name of the protein molecule, its function and the site of production. (4 marks)
Protein Function Site of
production
Insulin
Pancreatic cell
Haemoglobin
Breaks down starch
Salivary gland cell
c. Prions are protein molecules that can cause diseases like viruses. Both prions
and viruses are defined as non-living structures. Both can be transmitted from one organism to another. Prions have a different structure than the
organisms’ proteins and cannot be broken down by proteases.
i. List ONE structural difference between a prion and a virus. (1 mark)
____________________________________________________________
ii. Give a biological explanation why these proteins cannot be broken down
by proteases. (1 mark)
____________________________________________________________
____________________________________________________________
Total: 9 marks
Page 4 of 13 Biology – Year 11 – Track 3 – 2018
3. Give a biological explanation of the following:
a. The level of water in beaker Y remains constant while the level of water in
beaker X falls after 3 days. (2 marks)
Figure 3.1
____________________________________________________________
____________________________________________________________
b. People with damaged alveoli get breathless on climbing up the stairs while
those with normal alveoli do not. (2 marks)
Figure 3.2
____________________________________________________________
____________________________________________________________
Beaker X Beaker Y
Biology – Year 11 – Track 3 – 2018 Page 5 of 13
c. A mouse loses body heat to its surroundings very quickly while an elephant
loses body heat much more slowly when the surrounding environmental temperature is the same for both organisms. (2 marks)
Mouse Elephant
Figure 3.3
____________________________________________________________
____________________________________________________________
Total 6 marks
4. A new species of Pistol Shrimp was given the scientific nomenclature of
Synalpheus pinkfloydi. This crustacean has a large snapping, bright pink, claw. Its habitat is dead coral and crevices at the sea bottom. It uses the
snapping claw to stun small fish so that it can catch and eat them.
a. Name the phylum of Pistol Shrimp. (1 mark)
____________________________________________________________
b. List ONE characteristic of crustaceans. (1 mark)
____________________________________________________________
c. From the information given above, show why, this shrimp: (1, 1 mark)
i. is defined as a predator
____________________________________________________________
ii. is defined as a heterotropic organism.
____________________________________________________________
d. Name ONE abiotic factor that may affect the shrimp living at the sea bottom. (1 mark)
____________________________________________________________
Total: 5 marks
Page 6 of 13 Biology – Year 11 – Track 3 – 2018
5. In southern Morocco - a dry, hot region - goats climb the thorny Argan trees
and eat the olive-like fruits of the tree. In autumn, when ground vegetation
is lacking, goats spend 74% of their foraging time on tree-top grazing. Goats
are ruminants (fore–gut fermenters) and these goats spit out the seeds during regurgitation of food.
a. State ONE structural characteristic of ruminant herbivores. (1 mark)
____________________________________________________________
b. In a food chain or food web, list the trophic level where goats would be found.
(1 mark)
____________________________________________________________
c. The spitting of seeds by the goats is an animal seed dispersal mechanism.
i. Name ONE other type of seed dispersal. (1 mark)
____________________________________________________________
ii. Explain the ecological importance of goats spitting out the seeds after
regurgitation, away from the mother tree. (2 marks)
____________________________________________________________
____________________________________________________________
d. Explain how, the fact that goats are ruminants, helps in the digestion of the
food they eat. (2 marks)
____________________________________________________________
____________________________________________________________
e. Argan trees have extensive roots. Give TWO advantages of this. (2 marks)
____________________________________________________________
____________________________________________________________
Total 9 marks
Biology – Year 11 – Track 3 – 2018 Page 7 of 13
6. Figure 6.1 shows the menstrual cycle of a human female.
Figure 6.1
a. Use the diagram to determine:
i. the length of an average menstrual cycle (1 mark)
____________________________________________________________
ii the range of dates that an egg could be released from an ovary if a woman’s menstruation started on 8th January. (1 mark)
____________________________________________________________
b. Name the hormone secreted by the pituitary that stimulates ovulation to
occur. (1 mark)
____________________________________________________________
c. State the number of chromosomes found in a human ovum. (1 mark)
____________________________________________________________
d. One of the first signs of pregnancy is that menstruation stops. Explain why this is so. (2 marks)
____________________________________________________________
____________________________________________________________
Total 6 marks
Page 8 of 13 Biology – Year 11 – Track 3 – 2018
7. The set-up below shows 5 jars, all with a mixture of sugar, yeast, water and
foam (bubbles of a particular gas) forming on top of this mixture at different temperatures. The height of the foam i.e. from the mixture to the top of the
foam is an indication of the rate of reaction. In this investigation, oxygen is
present in the jars.
Figure 7.1
a. i. List the type of respiration occurring in the jars. (1 mark)
____________________________________________________________
ii. Name the gaseous product of this type of respiration. (1 mark)
____________________________________________________________
b. From your observations, explain how the rate of reaction varies with
temperature. (2 marks)
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________
c. Give a biological explanation of this variation in rates of reaction. (2 marks)
____________________________________________________________
____________________________________________________________
20 °C 30°C 40°C 50°C 60°C
Foam
Mixture
of yeast,
sugar
and water
Biology – Year 11 – Track 3 – 2018 Page 9 of 13
d. The following are the results obtained.
Temperature (°C) 20 30 40 50 60
Height of foam (cms) 5 11 22 18 15
i. Draw a graph of the height of foam (cms) against temperature (°C).
(4 marks)
ii. State ONE variable that needs to be kept constant in this investigation.
(1 mark)
____________________________________________________________
iii. State the conclusion derived from this investigation. (2 marks)
____________________________________________________________
____________________________________________________________
Total 13 marks
Page 10 of 13 Biology – Year 11 – Track 3 – 2018
Section B: Answer question 1. Choose any TWO other questions from
Q2 to Q5. Write your answers on a separate A4 paper.
1. Read the following text and answer the questions:
New research from University of Alberta and University of Vienna microbiologists provides
unparalleled insight into the Earth's nitrogen cycle, identifying and characterizing the
nitrifying bacterium, Nitrospira inopinata. The findings, explained Lisa Stein, co-author and professor of Biology, have significant implications for climate change research.
"Humans are now responsible for adding more fixed nitrogen, in the form of ammonium, to
the environment than all natural sources combined. Because of that, the nitrogen cycle has
been identified as the most unbalanced biogeochemical cycle on the planet."
Earth's nitrogen cycle has been thrown significantly off balance by the process we use to make fertilizer, which adds massive quantities of fixed nitrogen, or ammonium, to the
environment. This has huge environmental implications, from dead zones (low oxygen areas
where aerobic organisms do not survive) in our oceans to a greenhouse gas effect 300 times that of carbon dioxide on a molecule to molecule basis.
The Nitrospira inopinata microbe outcompetes nearly all other bacteria in its nitrifying
property in the environment," explained Stein. "Now that we know how efficient this microbe
is, we can explore many practical applications to reduce the amount of ammonium that contributes to environmental problems in our atmosphere, water, and soil. The applications
range from wastewater treatment, with the development of more efficient biofilms, to
drinking water and soil purification to climate change research.
An efficient complete nitrifying agent, such as Nitrospira inopinata, may produce less nitrous oxide. "By encouraging our microbe to outgrow other, incomplete nitrifying agents, we may,
in turn, reduce their contribution to the greenhouse gas effect. Further investigation is
required." Adapted from https://www.sciencedaily.com/releases/2017/08/170823142427.htm
a. i. Explain the importance of nitrification in the nitrogen cycle. (2 marks)
ii. Name ONE process in the nitrogen cycle that produces ammonia/ammonium compounds from dead, decaying matter. (1 mark)
iii. Name the association between leguminous plants (having root nodules) with the nitrogen fixing bacteria living in these nodules. (1 mark)
iv. Describe the role of the nitrogen fixing bacteria. (1 mark)
b. Nitrospira inopinata is a spiral shaped bacterium with a flagellum.
i. Bacteria are prokaryotic cells. Explain. (1 mark)
ii. State the role of the flagellum. (1 mark)
c. Ocean dead zones are caused by eutrophication.
i. Describe how ammonium in fertilisers end up in oceans and sea bodies. (1 mark)
ii. Define eutrophication. (2 marks)
iii. Explain how eutrophication results in dead zones. (2 marks)
d. Carbon dioxide is an air pollutant and a greenhouse gas. Describe the effect of greenhouse gases on the global environment. (3 marks)
Total 15 marks
Biology – Year 11 – Track 3 – 2018 Page 11 of 13
2a. Jan Baptiste Van Helmont performed the first investigations on photosynthesis. He
took a small willow tree of known mass and planted it in a known mass of dry soil.
He watered it for 5 years. After 5 years he weighed the willow tree and the mass of soil separately. The mass of soil did not change but that of the tree did. The
diagram below shows the results obtained.
Adapted from https://image.slidesharecdn.com/vanhelmont-110903190829-phpapp02/95/van-helmont-12-
728.jpg?cb=1315119144
Van Helmont therefore concluded that water is necessary for the growth of plant.
i. Name ONE substrate, other than water, necessary for photosynthesis to occur. (1 mark)
ii. Give the energy conversion occurring during the process of photosynthesis. (1 mark)
iii Explain how the process of photosynthesis contributes to the growth of the tree. (4 marks)
iv. Plants need mineral ions for growth. List ONE mineral ion important for plant growth and describe the function of this mineral ion. (1, 1 mark)
b. The figure below shows the procedure to decolourise the leaf before testing for starch.
Adapted from https://image.slidesharecdn.com/chap7-1211011174526925-9-110831064226-
phpapp02/95/nutrition-in-plants-28-728.jpg?cb=1314773491
i. Name the organelle that contains the pigment chlorophyll in a cell. (1 mark)
ii. Continue the procedure, shown above, to test the leaf for starch. Include the
next step/s, the chemical you would use and the result obtained. (3 marks)
c. Limiting factors reduce the rate of photosynthesis in plants. List the limiting factor
that is likely to have the greatest effect on plants in an open field on a warm sunny
day and give a reason for your answer. (1, 2 marks)
Total: 15 marks
Page 12 of 13 Biology – Year 11 – Track 3 – 2018
3. Red blood cells, white blood cells, platelets and plasma are components of blood.
a. i. Give the functions of white blood cells and platelets. (1 ,1 mark)
ii. The shape of a red blood cell is different from other human cells. Describe
the shape of the cell. (1 mark)
iii. Explain the importance of this shape. (1 mark)
b. Anaemia is a deficiency disease. People suffering from anaemia have fewer red blood cells than normal.
i. Name the mineral deficiency that causes anaemia. (1 mark)
ii. List ONE deficiency symptom of anaemia. (1 mark)
c. Sickle cell anaemia is an inherited disorder caused by an autosomal recessive
allele h. The allele H codes for the normal haemoglobin.
i. Define the term autosome. (1 mark)
ii. Two parents that show no symptoms of sickle cell anaemia have a child with sickle cell anaemia. Use a genetic diagram to include and explain the
genotypes of the parents, their children and the expected probability of sickle
cell anaemia children. (4 marks)
d. A nurse investigated the effect of exercise on the heart rate of three people using
a stress test. A person initially walks slowly on a treadmill. The speed is increased
slowly for 10 minutes. The following results were obtained.
Person Heart beat rate
per minute
BEFORE EXERCISE
Heart beat rate
per minute
AFTER EXERCISE
Time taken for the
heart beat to
return to before exercise (min)
1 59 98 3
2 66 112 6
3 69 140 10
i. The doctor concluded that person 1 is the fittest. Using the table above give
TWO reasons for this conclusion. (2 marks)
ii. State TWO other changes in the body, during exercise, other than an increase
in heart beat rate. (2 marks)
Total 15 marks
Biology – Year 11 – Track 3 – 2018 Page 13 of 13
4. Soil is composed of living and non-living matter that interact together. Soil plays
an important role in ecological cycles including carbon, nitrogen and water cycles.
Soil contains a multitude of different organisms that play a role in soil quality and support plant growth.
a. Give a biological explanation for these functions of soil.
i. Soil is a medium for plant growth. (2 marks)
ii. Soil is an ecosystem. (2 marks)
b. The table below shows three soil samples with the percentage of water found in
the soil. All three soils were given the same amount of water before readings were taken.
Soil sample A B C
% of water
found in the soil
8 18 27
i. Describe how you would find and measure the percentage of water found in
soil. (4 marks)
ii. Describe what type of soil you would expect soil sample A to be. Explain.
(1, 1 mark)
c. Explain how leaf litter and animal remains become humus. (3 marks)
d. List TWO functions of humus in soil. (2 marks)
Total 15 marks
5. Give biological explanations for the following statements:
a. Thermoregulation is a homeostatic action. (3 marks)
b. Human insulin injected to diabetic patients is produced and secreted from E. coli
bacteria. (5 marks)
c. In the pea plant germination, the pea seed cotyledons remain in the soil and do
not play a role in photosynthesis. (3 marks)
d. Riding a bicycle involves the cerebrum, cerebellum and medulla oblongata.
(4 marks)
Total 15 marks