KULUBI SECONDARY SCHOOL

57. According to the fluid mosaic model of menbrane structure A. proteins form a layer on top of the phospholipid bilaycr B. phospholpids form only inner half of the plasna membrane C. protems are located only on the outer half of the plasma membrane. D phospholipids form a bilayer in which proteins are studded 58. The function of the plant vacuole in maintaining rigidity of the cell is explained by its A. constant gaining and losing of water. B sphernical shapeand elasticity. C. determining biological clock of a cell. D. regulating cell division. 59. A student took two eggs, removed their shell using vincgar and put one in distilled water and the other in concentrated sodium chloride solution. She waited for 24 hours and recorded changes in weight and shape of the two eggs. From this, we can realize that the studentis attempting to demonstrate the process of A activetransport. C. endocytosis. B. Osmosis. D. exocytosis. 60. Electron donors and acceptors are important in aerobic respiration because they phosphorylate glucose to glucose phosphate. A. phosphorylate glucose to glucose phosphate. B. breakdown glucose into two molecules of phosphoglycerate. C. decarboxylate pyruvate during anaerobic respiration, D carry hydrogen to the electrontransport system. 61. Which one of the following reactions takes place under anacrobic condition in animal cells? A C6H12O6 ->2C2H5OH + 2C0, + 2ATP B C6H12O6 --2C3H6O3 + 2ATP C C6H12O6 -2C3H6O3 +36ATP D C6H12O6 ->2C2H5OH + 2C02 + 36ATP 62. During prolonged physical exercise, the muscles get fatigue. This is caused by accumulation of A. carbon dioxide C acetylcoA. B. ethanol. D. lactate. 63. When you compare the metabolic pathways of proteins,polysaccharnides and lipids. generallyconverge inthe A. glycolysis B link reaction. C Krebs cycle. D electron transport chain. 64. What are the parts of the plant cell where the light-dependent and independent reactionstake place respectively? A. Chloroplast and cytoplasm B. Mitochondrion and chlorophyll C. Thylakoid membrane and stroma D. Grana and mitochondrion 65. During glucose synthesis in the light-independent reactions of photosynthesis A three Calvin cyclesare used to make one glucose. B oneglycerolphosphate is released as the final product. C fixationofcarbon dioxideoccurs at the RuBP regenerationphase. D reduced NADP isused to reduce glyceratephosphate. 66. Despite the increased light intensity, the rate of low.This is due photosynthesis may remain to the effect of A low carbon dioxide concentration. B low temperature. C low oxygen concentration. D high humidity ofair. 67. Which ofthefollowing events occur during photorespiration? A. Rubisco binds with oxygen in the peroxisome. B. The Calvin cycle take place in the mitochondrion. C. CO2,and NH3 are produced in the cytoplasm. D Inorganic phosphate is released in the chloroplast. 68 1dentify the correct statesentabout the leaf structure of C3 plants A. Most of the chloroplasts are found in the palisade cells. B. The stonata are mninly fouad on the upper surface of thelcat. C. Palisade mesophyll cells are ncarest to lower epidemmis, D. Spongy mesophyll cells are nearest to the upper epidemmis.

99. What will happen if the concentration of greenhouse gas in the atmosphere is close to zero? A. Polar ice will melt and flooding Will devastate life on Earth. B. The temperature of the earth will drop to very low. C. Heat energy can't be radiated back to space. D. The earth becomes conducive for living things. 100. Which one of the following is NOT the efect of climate change on agricultural productivity? A. Reduction in precipitation of an area leading to reduced access to food. B. An increase in water availability due to increased transpiration leading to improved crop production. C. An increase in carbon dioxide concentrationthat leads to reduced crop production. D. Increase in the temperature of the earth leads to reduced crop production.

69. . Which one of the following comparisons is correct about C3 and C4 plants? A. C3 plants are advantageous in hot and dry environments. B C4 plants do not use the Calvin cycle to synthesizeglucose. C. C3 Plants containthylakoid in the bundle sheath cells. D. C4 plants are efficient at low CO2 concentration 70. Which one of the following comparisons is correct about C3 and C4 plants? A. C3 plants are advantageous in hot and dry environments. B C4 plants do not use the Calvin cycle to synthesizeglucose. C. C3 Plants containthylakoid in the bundle sheath cells. D. C4 plants are efficient at low CO2 concentration 71 The main roles of bacteria in the environment is its involvement in A material recycling C pollution. B biomagnification. D assimilation. 72. According to germ theory, which one of the following is a confirmation that a disease is caused by an infectious micro-organism? The micro-organism A. should be unable to grow in a culture. B must be present when the diseaseis present. C should not necessarily be presentwhen the disease is present. D. can show different symptoms in different host 73. Which one of the following statements is INCORRECT about mutation? A It results from errors in DNA replication during cel diviston. B Most mutations can be detectedand repaireu C. Most mutations affect the coding genes. D The rate of mutation can increased by mutagens 74. Evolutionary school of thought that incorporates the knowledge of inheritancewith the mechanisms of natual selection A. Lamarckism. C Panspermia B. Neo-Darwinism. D Darwinism. 75. Which one ofthe theories of origin of life has been undoubtedly disproved using experimental evidence on rotten meat? A. Special creationism B Spontaneous generation C. Biochemical origin D Eternity of life 76.. Which category ofevolutionary evidence allows us to understand organisms that lived inthepastbut currentlyextinct? A. Comparative biochemistry B. Comparative embryology C Animal breeding D. Paleontology 77. In a population of Galapagos finches, individuals that have shorter or longer beaks had a better success of picking food compared to those that have average beak length. What is the mode of natural selection operating in thi s population of finches? A. Disruptive selection B. Directional selection C. Stabilizing selection D. Normalizing selection 78. Which hominid species have a brain size smaller than the others? A. Home erectus B Home neanderthalensis C. Homo sapiens D. Homo hablis 79. Which of the following is corect about the key role of biology in helping to have food security? A. Providing health care services B. Producing nutritious staple crops C Producing machinery for food production D. Providing barrier to food access 80. In a certain dairy processing factory, experts use variety of microorganisms to make different dairy products according to their customers need. Which of the following dairy products is corectly matched with the type of microorganism acting on it? A. Skim milk - Streptococcus lactis B Acidophilus milk- Streptococcus Cremoris C. Buttermilk- Streptococcus diacetylactis D. Yogurt -Streptococcs lactis 81. Of the following bacterial species, which one is the causative agent of Syphilis? A Treponema pallidem B. Clostridium tetani C. Neisseria meningtidis D. Bordetella pertussis

Dina Mohammed: 82. Conjugation is one type of sexual reproduction occurring in the protozoa. Which of the following is true about the process of conjugation in paramecium? In the process A. mating occurs between individuals. B two individuals exchange haploid micronuclei. C. mitosis of micronuclei produces four haploid micronuclei. D meiosis of micronuclei produces two diploid micronuclei. 83. Supposea grade I2 students want to do an experiment on microbiota of human. From which part of the human body do they get more divers and dense microbial population compared to others? A Small intestine and reproductive tract B. Small intestine and large intestine C. Urinary tract and reproductive tract D. Oral cavity and upper respiratory tract 85. Suppose a biology teacher conducted an experiment on spinach leaves to show the presence or absenceofstarch to his students. He prepared an iodine solution and a green leaf for the experiment. Then, he boiled the green leaf to kill the cytoplasm and denature the enzyme. He inserted the leaf in hot alcohol to decolorize it. Finally, he dropped an iodine solution to decolorized leaf. What colour does he expect if the leaf has a starch in it? A. Yellow C. Purple B. Blue D. Red 86. One of the following is coect about the process of glycolysis. It occurs in A. the mitochondria of a cell and produces ATP B. The matrix under aerobic condition. C. Cytoplasm under anaerobic condition, D. The cytosol and mitochondria in anaerobic condition 87.Suppose a person eats sugarcane to get energy and then his body changes the Sucrose found in the sugarcane to glucose molecules. If his body earned 5 molecules of glucose, what is the calculated amount of energy yield in the form of ATP from such glucose molecules during aerobic respiration? A 38 C. 180 B. 72 D 190 88. Which of the following is the end product when yeast anaerobically ferments a glucose molecule? A Pyruvate C Acetaldehyde B Ethanol D. Glucose 89. Which one of the following evidences of evolution is acceptable by the evolutionist? A. Comparaitive embryology assumes that a continued use of a certain organ can lead to the development of an organ that is passed to the offspring B. Comparative anatomy assumes that organisms having similar anatomical features are evolutionarily closely related. C. Paleontology assumés that the development of vertebrate embryos shows similarities before they born. D. Comparative biochemistry assumes that similarities between organisms are based on the comparison of their fossil in the present to their ancestors. 90. Suppose two closely related butterfly speciesfeedingon different plants that have different agro ecological characteristics remained isolated and could not reproduce. What type of isolation is this? A Habitat C Mechanical B Allopatric D Geographic 91. One of thefollowingaltemativesis corect about the cause of speciation A. Allopatricspeciation is caused by ecological isolation. B. Allopatric speciation is the result of temporal isolation. C. Sympatric speciation is the result of reproductive isolation. D. Sympatric speciation is caused by geographicalisolation 96. Which ofthe following eye defectsis caused by the presence ofiregular eye shape? A. Long sight C. Short sight B Shorteye ball D. Astigmatism 97. Which ofthe following hormones controlsthe activity of circadianrhvthms? A. Adrenaline C. Aldosterone B. Melatonin D. Oxytocine 98. Which structure of human kidney is corectily matched with its respective Bowman's capsule -site of urine is concentration function? A. Bowman's capsule --site of urine is concentration. B. Loop of Henle --site of blood ultrafiltration C. Renal pelvis-- site where urine is collected and directed to the ureters D. Second coiled tubule - site of Ion reabsorption from the glomenular filtrate

54. Which cells one of the following is NOT included as part of the cell theory? All A arethebasic unit oforganis mns. B. have membranebounded organelles. D. come from pre-existing cells. have basically the same chemical composition. 55. A researcher studied prokaryotic and eukaryotic cells and identified them by just by analyzing the ribosomes. This was possible because A. eukaryotes have ribosomes while prokaryotesdo not. B. prokaryotes have 70S ribosomes while ribosomes. eukaryotes have 80S C. the ribosomes of eukaryotes are synthesized in the cytoplasm. D theribosomes of prokaryotes are bounded by membrane. 56. In addition to making the boundary ofcells and controlling materials into and outof transport of cells, theplasma membrane also has a function of A. storing energy. C. cell division. B detoxification D. cell signaling

In the above diagram, secondary consumers are indicated by numbers A. 4, 7, 8 and 10 C 1, 3, 4 and 7 B. 5, 6, 9 and 10 D. 3, 4, 6 and 10 21. Which green plants and microorganisms are highly important in the nitrogen cycle? A. Legumes and desulphovitbreo bacteria B. Pteridophytes and fungi C. Legumes and denitrifying bacteria D. Liverworts and nitrifying bacteria 22 From the following groups, select the one that contains all characteristics that are used by polar bears to adapt to very cold climates. A. Large size, thick fur, small ears and white camouflage B. Large size, thin fur, big ears and white camouflage C. Small size, thick fur, big cars and black camouflage D. SmallI size, thin fur, small ears and black camouflage 23. Developing plant varieties that secrete their own pesticide is an application of biotechnology in the area of A. Medicine C. Agriculture B. Food. D. Energy. 34. Which stage of the mitosis is characterized by fomation oftwo new nuclei at the end of polesof the cell? A. Prophase C. Anaphase B. Metaphase D. Telophase 25. If in l800 offspring, 900 are bb and 900 are some other genotype, which of the following are the most probable genotypes of the parents? (Hint: 'B' dominant allele and 'b is recessive allele of a pair) A. Bb and Bb C. Bb and bb B. BBand Bb D. BB and bb 26. Which one of the following is true about chromosomes? They are A. Circular structures located in the cytoplasm B. Thread-like structures located in the nucleus,. C. Known to consist genes but not found in nucleated cells: D. The same both in structure and in numbers in all organisms. 27. The following phrases refer to the importance of breeding. I. Minimize genetic diversity II. Makethe bestpossible use ofour resources III. Feed our population IV. Maintain our genetic diversity Which of the above phrases correctly indicate the importance of breeding? A. I, II and IIII C. II, IlI and IV B. I, Il and IV D. l , III and IV 28. Areas of the human brain that deal with smell, balance, and vision are respectively A. Fore brain, mid brain, and hind brain B. Mid brain, fore brain, ,and hind brain C. Hind brain.,midbrain, and fore brain D. Fore brain, hindbrain, and mid brain 29. In the nervous system of your body, the electrical signals travelling along the neurons is termed as A. Synapse. C. Grey matter. B. nerve impulse. D. neurotransmitter 30. Which disease is arise due to the effect of heavy alcohol drinking? A. Cirhosis of the liver B. Gastrointestinal disease C. Lung disease D. Lip cancer 31 Among the following parts of the ear, which one is filled with a liquid? A. Tympanum C Oval window B. Eustachian tube D. Sacculus 32. The following are causes of eye defects. I. When lens is too curved. II. Lens is normal but the eyeball is short iii. When lens istoo flat IV. Lens is nomal but the eyeball is long Which of the above causes results in short sightedness? A I and II C. II and IlI B. I and IV D. Il and IV 33. When your head is tilted on one side, your ear is involved in maintaining balance.This is initiated first by moving otoliths A In the opposite direction and pressingthe sensory hairs. B. In the same direction and pressing the sensory hairs. C. Up and down and pressing the sensory hairs D. In circular manner and pressing the sensory hairs.

The above diagrarm represents the structure of A. Cellulose C. Amino acid. B. Triglyceride D. Amylopectin. 50. A student conducted an experiment to identify the composition of an unkaown food sample. The food sample was positive for Benedict's test only after boiling it with equal volume of hydrochloric acid and neutralizing it. Which one of the following chemical formula most likely represents the organic molecule in the unknown food sample? A. C6H12O6 C. C12H24O11 B. C12H22O11 D C6H22O11 51. Select the one that fully describes the enzyme properties. Enzymes are A. All proteins, can be used over and over again, and affected by pH. B. Specific, can be used over and over again, and not aflected by pH. C. Not specific, speedup a reaction without being used up, aftected by inhibitors. D. All lipids, altered by a reaction, and destroyed by excessive heat. 52. The enzyme designated as EC 2.5.11.1 can be grouped in which one of the followine classes? A. Isomerases C. Oxidoreductases B. Hydrolases D. Transferases 53. Identify the corect order of enzyme action according to the induced-fit model. A. Substrate entering active site of enzyme ➜ products leaving active site of enzyme ➜ enzyme -substrate complex ➜ enzyme- products complex B. Substrate entering active site of enzyme ➜ products leaving active site of enzyme ➜ enzyme -products complex ➜ enzyme-substrate complex C. Substrate entering active site of enzyme ➜ enzyme -products complex ➜ enzyme substrate complex ➜ products leaving acive site of enzyme D. Substrate entering active site of enzyme ➜ enzyme-substrate complex ➜ enzyme - products complex ➜ products leaving active site of enzyme 54. For which one of the following ezymes copper ions can be used as a cofactor for cupper ions? A. Cytochromne oxidase B. Carbonic anhydrase C. Alcohol dehydrogenase D. Oxidoreductase 55. Which one the fllowing statement is corect for a reaction that contains substrate molecules for every competitive inhibitor molecule? A The collision between the enzyme and the substrate will be 85% B. The rate of the reaction will drop to 15% maximum. C. The reaction will be 85% inhibited. D. The collision between the inhibitor and the enzyme will be 37%

35. What is the effect of removing the apical dominance? It makes the plant to A. grow upwards without limit B. bush out and produce side branches C. produce less leaves and branches D. effective in water preservation