SECTION A MCQ
1
A
21
D
2
C
22
B
3
D
23
C
4
C
24
A
5
B
25
D
6
C
26
B
7
B
27
D
8
A
28
D
9
A
29
B
10
B
30
A
11
B
31
B
12
C
32
A
13
B
33
A
14
A
34
C
15
B
35
B
16
C
36
D
17
A
37
D
18
B
38
C
19
B
39
C
20
C
40
D
Section B
B
1a
(i) Carbon dioxide + water à glucose + oxygen
(ii) Water à oxygen + hydrogen
(iii)Magnesium + oxygen à magnesium oxide
Each correct [1]
b
Chemical changes are both harmful as well as useful [1]
Harmful – rusting of metals, decomposition of food [1]
Useful – photography [1] any two point [2]
c
Crude oil [1]
Distilled and mixed with other chemicals [1]
Used to make plastics, petrol, paint [1] any 2 point [2]
d
ii
iii
One sodiunn
One oxygen
One hydrogen
iv
1 copper atom
1 sulphur atom
4 oxygen atoms
Number of atom /size correctly drawn for each [1]
correctly shown the name of atom in each molecules [1]
B
2a
Stomach, Pancreas, Small intestines, Gall bladder.
2 correct [1] 3 correct [2] all [3]
b
Gall bladder store bile which break down large fats molecules into droplets [1] [1]without this organ the person diet should avoid fats [1]
c
Bile makes fats easier to digest [1] / break down large fats droplets to small ones [1]. Lipase digests fats into fatty acids and glycerol[1].
d
Gastric juice in stomach produces hydrochloric acid.Hydrochloric acid is sour[1].
Gastric juice has protease which digests protein into peptones[1].Lumpy mass is because food is not digested fully[1].
3a i
A à Aorta [1] B à Vena Cava [1]
Ii
iii
A -- Oxygenated blood [1] B-- Deoxygenated blood [1]
The oxygenated and deoxygenated blood will be mixed together [1]
b
The blood goes from the heart to the lungs and back again and
blood goes from the heart [1] to the rest of the body and back again [1].
Arteries
Veins
Carry blood from heart
Carry blood to heart
Carry oxygenated blood (except pulmonary artery)
Carry deoxygenated blood (except pulmonary vein)
Thick muscle wall
Thin muscle wall
Narrower lumen
Wider lumen
No valves
Valves present
Carry blood at high pressure/ blood in pulses/ high speed
Carry blood in low pressure/ blood not in pulses/ slow speed
Any one comparison points for both [1] total [5]
4
ai
2 [1]
aii
Day 4, Day 32 [1]
bi
Fertilisation has taken place [1]
bii
the increase in the lining of the uterus in preparation for the growth of the baby.[1]
SECTION C (20 marks) only select 2 questions
C
1a
(i) When mongooses were introduced, they ate the mice which were in abundance. [1] Thus population of mongoose began to increase while the number of mice was reduced. [1] As the number of mice became scarce, the mongoose started to feed on the lizards [1] and ground nesting birds[1] and even snakes [1], thus reducing their population. As a result, the insects population started to grow, causing more harm to the plants [1].
B i
Plants à insects àground nesting birds à snakes àmongooses
Any 2 correct [1] four correct [2] all [3]
ii
Before introducing a species into the habitat, every detail about the species [1], e.g its eating habits , its reproduction rate and impact of that organism on other species [1] (both plants and animals) should be studied.
2
a
To test if the white powder is corn starch, put 2 drop of iodine solution on the powder [1] the yellowish brown iodine solution will changed to bluish black[1]
To test if the white powder is baking soda, add the white powder to a tablespoon of vinegar[1], bubbles are observed [1]
To test if the white powder is sugar, heat the white powder the powder will turned brown then black upon heating [1]
If all the tests above are negative results, the white powder is likely a salt[1]
[1x4=4]
b
As condensation occurs, the gases particles lose energy [1].
The forces of attraction between the particular are stronger and the particles come closer together [1] and re-arranged a liquid state [1] in which the distance between the particles are smaller as compare to the gases particles[1]
3
a
(i)Ovary [1]; Produce eggs and female hormones.[1]
(ii) The other ovary can still produces eggs.[1] The egg from this ovary can still be fertilised.[1]
Millions of sperms deposited into vagina [1]by penis during sexual
intercourse[1].
Sperms swim pass uterus[1] to fallopian tubes and cluster around mature egg[1]. Fertilisation occur in the oviduct [1] when
the fusion of nuclei of sperm and egg[1].
End of paper
Wednesday, October 6, 2010
1c) Antibiotics at early stage of infection.
2a) i) produce sperms and male hormones ii) allow sperm production at below body temperature iii) to transport sperms to urethra iv) provide alkaline medium and nutrients for sperms v)deliver sperms to outside of body vi)to deposit sperms in vagina
b)wear a condom, keep to one sex partner
3a) menstruation, fertile and uterine thickening period
b) fusion of male and female sex cells vs depositing at uterine lining for development
ii) cutting and tying of sperms ducts vs cutting and tying of oviducts
c) a chemical which female takes to prevent ovulation
4a) Male- small Female-Big Male-Produced in millions Female-one matures every 28 days male-motile female-immotile
bi)produce ovum and female sex hormones ii)site of fertilisation and transport ovum to uterus iii) site of implantation and development of embryo iv)sperm reservoir v)where penis penetrate and deposit sperms
2a) i) produce sperms and male hormones ii) allow sperm production at below body temperature iii) to transport sperms to urethra iv) provide alkaline medium and nutrients for sperms v)deliver sperms to outside of body vi)to deposit sperms in vagina
b)wear a condom, keep to one sex partner
3a) menstruation, fertile and uterine thickening period
b) fusion of male and female sex cells vs depositing at uterine lining for development
ii) cutting and tying of sperms ducts vs cutting and tying of oviducts
c) a chemical which female takes to prevent ovulation
4a) Male- small Female-Big Male-Produced in millions Female-one matures every 28 days male-motile female-immotile
bi)produce ovum and female sex hormones ii)site of fertilisation and transport ovum to uterus iii) site of implantation and development of embryo iv)sperm reservoir v)where penis penetrate and deposit sperms
Friday, September 24, 2010
Revision Revision Pple
Past Revision Qns:
Chapter: Digestive System
1a) Explain why food must be digested. [2]
b) Describe digestion in the alimentary canal:
i) mouth ii)stomach iii)small intestine [6]
2a) Describe how food is moved through the oesophagus to the stomach. [2]
b)Explain how the small intestine is adapted for its functions. [6]
3a)Differentiate between the following terms:
i) absorption and assimilation ii) digestion and absorption iii) ingestion and egestion[6]
b) Discuss how different pH affects digestion. [2]
4a)What part does the liver play in the digestion and utilization of food substances. [4]
b) What are the functions of bile in the small intestine? What happens in the absence of bile? [4]
1(a)What is meant by a double circulation? [2]
(b)State the function of coronary arteries. [2]
(c)Describe how the circulatory system deals with bacteria which may have entered through a cut. [4]
2(a)Describe how the heart with its left and right chambers aid in the efficient transport of oxygen. [6]
(b)Why do red blood cells have a short lifespan? [2]
3a) Compare between the differences in terms of function, structure and composition of the artery, vein and capillary. [5]
b) What is the purpose of valves in the heart and veins? [1]
4a) Outline the pathway of blood flow through the double circulation. [2]
b) State the importance of a double circulation. [2]
c) List the components of the blood and their respective functions. [4]
5a) Compare between the following terms:
i) Translocation, Transpiration [2] ii)Xylem, Phloem [2]
b) Describe the conditions required for wilting and discuss the advantages and disadvantages of wilting. [2]
Chapter: STDs, Sexual Reproduction in Animals
1a) Discuss the medical importance of antibiotics [2]
b) Describe the symptoms of AIDs and discuss how it is different from syphilis. [4]
c) State how syphilis can be treated. [2]
2a) Describe the functions of the following structures:
i) testes ii)scrotum iii)sperm ducts iv)prostate gland v)urethra vi)penis [6]
b) Describe 2 ways in which males can protect themselves from STDs. [2]
3a) State 3 features of the menstrual cycle. [3]
b) Distinguish between the following terms:
i) Fertilisation and Implantation ii) Vasectomy and Ligation [4]
c) State what is a contraceptive pill and its effects. [1]
4a) Compare male and female gametes in term of size, numbers and mobility. [3]
b) Describe the functions of
i)ovaries ii)oviducts iii)uterus iv)cervix v)vagina [5]
Wednesday, August 25, 2010
Sunday, August 1, 2010
Now we investigate
Ok you should know now that all of you got to write up your own experiment to investigate on how a particular factor you are interested in affects the rate of photosynthesis and eventually investigate on the main big experiment to answer.(important to indicate what you can measure to show rate amount of photosynthesis)
what is the best conditions for photosynthesis in the science lab?
Remember to post on your blogs, how your experiment is to be carried out and comment on each other's experiment to help see if there are any other ways to do the experiment or maybe some lab safety issues or maybe there is something wrong with the experiment such that the errors are so huge that you are unable to produce any results. SO don't forget, HELP EACH OTHER OUT!
Some links on how to write an experiment:
http://www.teachers.ash.org.au/jennies/pracreports.htmhttp://www.unc.edu/depts/wcweb/handouts/lab_report_complete.html
http://www.adhs.act.edu.au/study_guide/prac_reports
Please submit your list of required apparatus and materials ASAP!!!
Even weirder facts on photosynthesis
In the Dark
In 2005, a team of scientists discovered the first organism that relies on photosynthesis yet lives in a part of the ocean that never gets sunlight. Researchers said their findings of photosynthesis in the dark point to the possibility of similar life on other planets
Photosynthesis In Animals
Animals need other animals or plants for food energy, but Texas A&M researchers are studying a sea slug that creates its own energy through photosynthesis. The sea slug eats algae but doesn't fully digest it. What remains in its system "continues to photosynthesize and provide food for the slug," similar to what a plant does.
In 2005, a team of scientists discovered the first organism that relies on photosynthesis yet lives in a part of the ocean that never gets sunlight. Researchers said their findings of photosynthesis in the dark point to the possibility of similar life on other planets
Photosynthesis In Animals
Animals need other animals or plants for food energy, but Texas A&M researchers are studying a sea slug that creates its own energy through photosynthesis. The sea slug eats algae but doesn't fully digest it. What remains in its system "continues to photosynthesize and provide food for the slug," similar to what a plant does.
Monday, July 26, 2010
Green Machines
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