70003-Kenya-KCSE-S4-2019-Biology-1-Practice-Past-Exam-Premium Welcome to your 70003-Kenya-KCSE-S4-2019-Biology-1-Practice-Past-Exam-Premium Exam Title: KCSE Past Papers 2019 Geography paper 1 SG Exam ID: 70003-Kenya-KCSE-S4-2019-Biology-1-Practice-Past-Exam-Premium Country: KENYA LEVEL: KCSE (Secondary Leaving) SUBJECT: Biology Paper I YEAR: 2019 TYPE: CBE (Computer Based Exam) INSTRUCTIONS and Notes: This is a practice past exam that was prepared by Standard Gateway, an education and technology focused organization and out partners. The exam shall assess examinee preparedness in a computer based format We ask that no one shall copy, redistribute without appropriate express written approval by Standard Gateway staff, in ensuring the exam is beneficial to other examinees ALL QUESTIONS ARE TYPE OF MULTIPLE ANSWERS,MULTIPLE CHOICE,TRUE OR FALSE AND FILL IN THE GAP CHOOSE YOUR ONE OR MULTIPLE ANSWERS TO THE QUESTIONS BY CLICK. DURATION: 1Hours (May or may not be enforced in the exam), Examinee May have to Self Monitor This exam is a lite Version Accessible for free - A Premium Version is accessible at a minor fee through purchase of an access Code Below is an illustration of a piece of apparatus strategically positioned to trap some organisms.Name the apparatus labelled E.Spray.Container.Pooter/Aspirator.Test tube. Below is an illustration of a piece of apparatus strategically positioned to trap some organisms.State the function of the part labelled E.To spray insecticide and pesticide.To measure the acidity of the tree gladly.To prevent dirt/insects from entering the suction tube/into the mouth.None of the answers. Below are diagrams of a cell organelle obtained from different organs of an animal.Select the correct statement for organelle named F corresponding to an organ in the urinary system where it likely to be found KidneyLoop of HenleNephronBladder Select correct statement for organelle named G corresponding to an organ in the urinary system where it likely to be foundProximal convoluted tubuleGlomerulus, loop of HenleBladder,ureter ,urethraDistal tubule From the following statement choose one corresponding to organelle labeled F.reabsorbs,Na+ and cl- from the interstitial fluid ,so that organelle F needed for transportation of ionsreabsorbs water ,ions and nutrients, removes toxins and adjusts filtrates PHActive reabsorption of solutes requires more energy;organelle F more cristae for attachment of more respiration enzymes producing more energyAll are correct answers From the following statement choose one corresponding to organelle labeled G.It does not require as much energy/organelle G has less number of cristae hence fewer respiration a enzymes producing attached/less energy producedreabsorbs water ,ions and nutrients, removes toxins and adjusts filtrates PHreabsorbs,Na+ and cl- from the interstitial fluid ,so that organelle F needed for transportation of ionsAll are correct answers 1 out of 10 Name the part of the chloroplast where the following reactions occur: Carbon(IV) oxide fixationStromaOuter membraneThylakoidGrana/granum Name the part of the chloroplast where the following reactions occur: PhotolysisStromaOuter membraneThylakoidGrana/granum During a practical investigation on food tests, students were provided with the following reagents.Benedict's solutionSodium hydrogen carbonateDilute hydrochloric acid.Identify the food substance the students were to testFood proteinsNon reducing sugarVitaminsFat During a practical investigation on food tests, students were provided with the following reagents.Benedict's solutionSodium hydrogen carbonateDilute hydrochloric acid. State the role of dilute hydrochloric acid during the experiment.To neutralize the acidChange acide into fats and waterTo hydrolyze/break down sucrose/ non reducing sugars to reducing sugars/glucose/fructose During a practical investigation on food tests, students were provided with the following reagents.Benedict's solutionSodium hydrogen carbonateDilute hydrochloric acid. State the role of sodium hydrogen carbonate during the experiment.To neutralize the acidChange acide into fats and waterTo hydrolyze/break down sucrose/ non reducing sugars to reducing sugars/glucose/fructoseAll answers are correct 2 out of 10 In an experiment on respiration, a mouse was observed to have inhaled 200 cm3 of oxygen and exhaled 199.75 cm3 of carbon(IV) oxide in ten minutes.The respiratory quotient for the activity in the experiment is.0.992750.967350.998750.83945 In an experiment on respiration, a mouse was observed to have inhaled 200 cm3 of oxygen and exhaled 199.75 cm3 of carbon(IV) oxide in ten minutes.Identify the possible food substance consumed by the mouse.Carbohydrates/glucoseWater/glucoseCarbohydrates/vitaminsAll of the above In an experiment on respiration, a mouse was observed to have inhaled 200 cm3 of oxygen and exhaled 199.75 cm3 of carbon(IV) oxide in ten minutes.State the fate of the excess of Carbohydrates/glucose in the human body. Evacuated outside the bodyStored in the body as fat/subcutaneous deposit/adipose tissueUsed in the combustion of nutriments to feed the bodyused in digestion of lipids The photograph illustrates a housefly at various stages of its development.Name the four stages of the life cycle of a larva.Egg, young, Larva, AdultEggs, child, Larva, AdultEggs, Pupa, Larva, AdultEggs, Pupa, Larva, Old Using arrows, link the stages of the life cycle in the correct order.Which one is the correct sequence of the life cycle of a fly?Adult->Eggs>Pupa>Larva>AdultAdult->Eggs>Larva->Pupa->AdultAdult->Eggs>Larva->teen>AdultAdult->Eggs>teen>Pupa->Adult Choose correct answer for the following statements concerning life cycles of a housefly and that of a cockroach The life cycle of housefly consist of four stages: egg, puppa, larva and adult The life cycle of a housefly consist of three stages: egg, nymph and adult The life cycle of housefly undergoes a complete metamorphosis The life cycle of housefly undergoes a incomplete metamorphosis 3 out of 10 State one advantage of the life cycle of a cockroach to itself.Presence of larva and pupa increases the its life; - (by increasing the resistance to the extreme environmental conditions)Absence of larva and pupa shortens the life cycle of the organism; - (avoiding adverse/extreme environmental conditions that would affect its growth/general life processes)With its complete metamorphosis, it will live longerA longer larva cycle helps avoiding adverse/extreme environmental conditions that would affect its growth/general life processes The following enzymes in the human digestive system are secreted in an inactive form. Pepsin amylase papain Trypsin chymotrypsin The diagram below represents a stage in the division of a cell.For a reason, identify the organism from which the cell was obtained.Stem cell in divisionAmoeba/ plasmodium reason Constriction of the cell membrane/ presence of centriolesThe DNA NucleusMitochondrial division Explain why short distance runners breathe quickly and deeply at the end of a race. To decrease the body temperature (in the tissues); To reduce risk of anemia (in the muscles) To increase the supply of oxygen (in the tissues); To reduce the consumption of body nutriments (in the tissues); To offset the "oxygen debt"/halt/manage the accumulation of lactic acid (in the muscles) State the function of a mirror in a light microscope.Reduce lights (by making a shade) to the objectStopping the object (illuminating the area)Reflects light (through the condenser) to the objectAmplify the refraxion capacity of visibility From the following which is (are) the reason(s) why the coarse adjustment knob should not be used to lower the high power objective. Can break the objective lens/cover slip/slide; Can confuse between the specimen and the other parts of the microscope Can destroy the specimen (making the microscope dirty) Can zoom the specimen and make it not visible 4 out of 10 State the effect of movement of the diaphragm muscles during inhalation in mammals. The diaphragm contracts and flattens; - leading to increase in volume of the thoracic cavity; push the lungs and make them push out the air Filter the air and let it enter the heart pure decreasing the pressure inside it, (forcing in the air) Which structural adaptations of leaves maximise efficiency in gaseous exchange. Thin leaf lining/epidermis for faster diffusion of respiratory ..) gases/ to reduce diffusion distance for respiratory gases; The horizontal position of the leaf which retain the air easily Numerous stoma to increase surface area for gaseous exchange; loosely packed cells in the spongy mesophyll region/ intercellular air spaces (lower layer) to allow for free movement of respiratory gases The green color which ease the penetration of air The set up below illustrates a certain physiological process. molecules of dy membrane (cross section) equilibriumName the physiological process.DiffusionPhotosynthesisRespirationTransfusion Give two examples of Diffusionabove in plants. Make enter the air in the plant Protection against parasites Lowering the temperature of the medium Retention of water from the air Absorption/uptake of mineral ions/salts State two ways by which the movement of dye molecules in the set up would be slowed down. Cover the membrane with chemical products like acids and salts Increasing thickness of the membrane; Use less dye/add more water/reducing the concentration gradient Expose the membrane to the solar radiation many hours 5 out of 10 Explain the survival values of the following tropic responses to plants.Geotropism Enables plants access water/mineral salts; Protect the plant against parasites Help in water and air penetration in the plant tissues Anchorage. Explain the survival values of the following tropic responses to plants.Phototropism.Kill bad parasites to plantsIncreases the water entering in the plantExposes plant leaves to light for photosynthesis/for formation of chlorophyllHelps to keep water in the plant and protect it from drying Name the causative agent for Tuberculosis.Mycobacterium lepraeMycobacterium tuberculosis/ Mycobacterium bovis.Vibrio choleraeSalmonella typhi The photograph below illustrates a germinating seedling.Name the type of germination illustrated in the photograph. EpigealHypogealCanonical GerminationHepigeal The photograph below illustrates a germinating seedling.Explain the function of each of the parts labeled G.Elongates to expose the foliage leaves to light photosynthesis.Elongates to expose the foliage leaves to water.Elongates to expose the foliage leaves to air.Elongates to expose the foliage leaves to nutrients. 6 out of 10 The photograph below illustrates a germinating seedling.Explain the function of each of the parts labeled H. Good respiration For photosynthesis (it is green); Protects plumule during germination Protect against drying Keeps nutrients intact Stores food (for growth); Explain the physiological process responsible for keeping young seedlings upright.Germination of seedsOsmosis - water moves into the cells becoming turgid - attaining mechanical support ; OWTTEPhotosynthesis - capture light and with nutrients creates proteinsRespiration - Oxygen enter in the plant and do the combustion of nutrients The following are text messages on a cellphone that represent gene mutation. Identify the type of gene mutation represented in ISubstitutionDeletionInversionInsertion The following are text messages on a cellphone that represent gene mutation. Identify the type of gene mutation represented in IISubstitutionDeletionInversionInsertion Complete with the right set of words to state Mendel's First Law.The (1) of an organism are determined by (2) (which occur in pairs). Only one of the genes can be carried in (3) and passed on to the next generation.(1) characteristics/traits (2) internal factors/genes (3) the gamete(1) characteristics/traits (2) the gamete (3) internal factors/genes(1) internal factors/genes (2) characteristics/traits (3) the gamete(1) internal factors/genes (2) the gamete (3) characteristics/traits 7 out of 10 State two disadvantages of genetically modified plant products. They don’t have enough productions/matter/volume Poor/undesirable qualities are perpetuated through subsequent generations; They develop slowly compared to their ancestors (natural plants) Most have lost most of the original (desirable) qualities eg taste; How is the surface area increased in the mammalian small intestines? Presence of numerous villi/microvilli; Being very big in size Having may pores inside Being long; Being highly coiled With its ovoid shape giving a curved inside area Below are diagrams representing developmental stages of three different vertebrates. Select one statement from the following evidence of evolution illustrated by the vertebrates in the diagram abovePresence of biodiversityPresence of gene and genomeComparative embryologyVertebrate are endoskeleton Below are diagrams representing developmental stages of three different vertebrates.The reasons why structure labelled J has been retained through the evolution of fish is:Because it’s specific changeTo be able to survive in environment they belong inFish is ancestor of other vertebratesFish remained in the aqueous media /aquatic habitat; well-developed tail;fin for propulsion movement Below are diagrams representing developmental stages of three different vertebrates. Choose one statement that is incorrect to explain the advantage of evolution has given human over most of other animals They not intelligent than other speciesThey have ability to fight against diseasePresence of variation in humans which gives them ability to adapt to environmentAbility to live long than other species 8 out of 10 The table below shows the percentage concentration of certain substances in blood plasma,glomerular filtrate and urine in a human being at a particular time. Choose a correct answer explaining the likely impact on composition of urine in case of following: Where are vigorous physical exercises?Less water and urea;since some is excreted/eliminated through the skin (as sweat )Much water and urea excreted through skin as sweatAmount of sugar excreted in urine increaseUrine is diluted because increase of water iritalee and leads to an increased urine output The table below shows the percentage concentration of certain substances in blood plasma,glomerular filtrate and urine in a human being at a particular time. Choose a correct answer explaining the likely impact on composition of urine in case of following: A meal rich in protein?Increased amount of urea in urine due to diminution of amino acidsDecrease amount of urea in urine due to diminution of amino acidsMore urine output produced as results of protein intakesun concentrated urine produced due to the removal of amino group from protein molecules(diamination) Choose the best name of the process responsible for:Presence of glucose in glomerular filtrate urinificationDeaminationultra filtrationSelective reabsorption Choose the best name of the process responsible for:Absence of glucose in urineUrinificationDeaminationultra filtrationSelective reabsorption Choose methods of fossil formation. Petrification/change into rock Putrefaction / change by anaerobic decomposition Growth of animal and vegetal beings Entire organism or parts preserved; Impressions (eg casts/moulds) 9 out of 10 The photograph below represents a leaf obtained from a certain plant.Account for the observations made if the leaf was tested for starch. The leaf stay green as i was before; Differences in distribution of chlorophyll/leaf is variegated; green patches would photosynthesize forming starch; If is dried and has no sign of photosynthesis at all giving blue-black colour with iodine solution unlike the regions without chlorophyll State two ways by which plants manage their solid wastes. Eliminates them by stomata Evaporation through the leaf pores Storage in tissues in non-toxic forms; Push them into the roots and are evacuated in the soil Deposited in plant tissues/organs- which age and fall off; (eg leaves, bark, fruits, flowers) Recycle into reusable nutrients The diagram below represent a set during an experimentWhat was the experiment investigating? Presence of acid in the plantsTo investigate how ants respond to moisture/water/ hydrotaxis (varied environments with/without moisture/ water)Quantity of plant nutrient in the soil before plantingPresence of pesticides in the soil The diagram below represent a set during an experimentState the likely identity for substance KSilica gel/anhydrous calcium chloride pellets/pyrogallic acid/dehydrating/ drying agentHydroxide / Acetic acidcalcium permanganate / copper / Sulfuric acidHydrochloric acid The diagram below represent a set during an experimentExplain why substance K is a drying agent?The colour of cobalt (II) chloride paper turned into black/all the moisture/ water vapour was absorbed/There was much water/moisture in the flask which change the colour of cobalt (II) chloride paperThe colour of cobalt (II) chloride paper remained blue/all the moisture/ water vapour was absorbed/There was no water/moisture in the flask to change the colour of cobalt (II) chloride paperThe odour of cobalt (II) chloride paper remained blue/all the moisture /water vapour was absorbed /There was no water/moisture in the flask to change the colour of cobalt(II) chloride paperThe odour of cobalt(II) chloride paper remained blue/ all moisture/water vapour was not absorbed/There was water/moisture in the flask to change the colour of cobalt(II) chloride paper What are the observations made in flask 2 in the experiment below:No ants were attracted/ moved into the flask; due to the absence of moisture/water vapour;(More) ants were attracted/ moved into the flask; due to the presence of moisture/water vapour; (evidenced by the change of cobalt (II) chloride paper to pink)No ants reacted to the experience;(More) ants were attracted/ moved into the flask; due to the presence of moisture/water vapour; (evidenced by the change of cobalt (II) chloride paper to silver) 10 out of 10 Time is Up!