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No expanded working has been attached for this question yet. The verified answer is Option A.

No expanded working has been attached for this question yet. The verified answer is Option A.

Agglutination during blood transfusion occurs when: - Red blood cells from the donor have antigens on their surface that are different from the recipient's antigens. - The recipient's immune system recognizes these foreign antigens and produces antibodies against them. - The antibodies bind to the antigens on the donor's red blood cells, causing them to clump together (agglutinate). This reaction can lead to serious complications, including hemolysis (red blood cell destruction) and even death. To prevent this, blood types are carefully matched before transfusion. The correct answer is option A. contrasting antigens and antibodies.

No expanded working has been attached for this question yet. The verified answer is Option B.

No expanded working has been attached for this question yet. The verified answer is Option D.

No expanded working has been attached for this question yet. The verified answer is Option A.

No expanded working has been attached for this question yet. The verified answer is Option B.

No expanded working has been attached for this question yet. The verified answer is Option A.

No expanded working has been attached for this question yet. The verified answer is Option C.

The diagram in III is the pupal stage of the mosquito. The adult form of it is the vector of elephantiasis Elephantiasis, also known as lymphatic filariasis, is caused by parasitic worms that are transmitted by the bite of an infected mosquito. The disease damages the lymphatic system, which can lead to severe swelling in the limbs and other complications.

No expanded working has been attached for this question yet. The verified answer is Option B.

(a) Types of refuse: (i) Specimen J is a dry refuse/waste. (ii) Specimen K is wet rey waste/sewage (b)(i) Animals vectors that breed on specimen J:- Rat, Housefly, -Cockroach Animal vectors that breed on specimen k Housefly: Blackfly; Female Aedes mosquito/female anopheles mosquito/mosquito; -Snail. (ii) Diseases associated with specimen J. Typhoid, plague, dysentery, cholera, diarrhea. (iii) Diseases associated with specimen K. Dysentery, diarrhea, cholera, typhoid, plague elephantiasis, yellow fever, malaria, ascaris infestation, Taenia, Bilharzia. (c) Methods of disposal (i) Rural area Specimen J: refuse dumps/Throwing into bush; Urban Area: Dumping into sea/Dumping Sites, Use of incinerator (ii) Rural Area : Specimen K:Pit latrine Throwing into backyard/bush Urban Area: Septic tank latrine Bucket latrine/gutters (d)(i) Effects of improper sewage disposal: - contamination of water bodies/water pollution, - offensive odor -source of diseases -soil pollution. (iii) Differences: Specimen J Specimen K Dry solid waste/contains little/no water Wet liquid waste/contain large proportion of water Can be Kept tor long period can not be kept for long period can be burnt can't be burnt Can be compacted/compressed Cannot be compacted/ compressed May not emit offensive odour Easily emits offensive odour Easily converted into organic manure Not converted into organic manure (iii) Importance of refuse to a farmer:- If buried it can be used as organic manure/enriches the soil.

No expanded working has been attached for this question yet. The verified answer is Option B.

(i) Effect of gravity on plant growth: The (main) root grows down in response to gravity/positively geotropic; the (main) stem/shoot/grows upwards away from gravity/negatively geotropic. (ii) Experiment to demonstrate the effect of gravity on the roots of a plant: - Select three germinating bean seedlings/seeds on a moist/damp sawdust/wet blotting paper Pin/keep one seedling in a horizontal position Place another seedling in a vertical position with the radicle pointing upwards Place the third upwards vertical with the radicle pointing downwards, to serve as control After few/2-3 days, it will be observed that the radicle of the seedling placed horizontally bends/ grows downwards the radicle of seedling placed vertically bends/grows downwards Indicating positive geotropism/ positive response to gravity. The seedling placed vertically with radicle point downwards did not bend. (N.B. observation must correspond with the experimental procedure to score). ALTERNATIVE to 1 (a) (ii) Take a clinostat and two bean seedlings Pin one seedling horizontally on damp/moist/wet/cotton wool/blotting paper attached to the cork of the clinostat Pin the other seedling onto some damp/moist/wet cotton wool/blotting paper attached to the cotton tile Start the motor of the clinostat; Observe the seedlings after 8 —10 hrs. It will be observed that the radical of the seedling placed horizontally bends/grows down wards Indicating/showing positive geotropism. (b) Detection of bitter taste in humans Taste buds are unevenly distributed on the surface of the tongue Taste buds for detecting bitterness are at the back/end of the tongue For a substance to be tasted it must be dissolved in a solution/saliva When bitter substance is dissolved in saliva, sensory cells at end/back of the tongue are stimulated Which pass impulses to the brain; Which interprets the taste as bitter. (c) Hormones of endocrine glands and their functions S/N Endocrine glands Hormone produced Function 1 Thyroid Thyroxin influences growth/development; Regulates/controls rates of metabolism 2 3 Pancreas Ovary/ovaries Insulin Oestrogen Control blood sugar level/causes liver to convert to convert glucose to glycogen Development of secondary sexual characters of females

(a) Diagram showing some organs of mammalian gut Title (T) (b)(i) Two diseases of the liver: Liver cirrhosis Amoebic liver abscess Hepatitis Cancer/tumor of the liver Gall stones. (b)(ii) Effects of liver diseases on humans: (i) Weakness and tiredness (ii) Jaundice/yel-lowish eye/skin (iii) (Slight) fever (iv) Oedema/ swollen abdomen/accumulation of fluid in the abdomen (v) High blood pressure (vi) Loss of weight (vii) Abdominal pain (viii) Loss of apetite (ix) Headache (c) Deficiency Symptoms Vitamin A: Night blindness /poor vision Colds/bronchitis Dry scaly skin. Vitamin C: Swollen joints/scurvy/bleeding gums/sore mouth low resistance to infection dental disorders. Vitamin K: - Excessive bleeding/haemorrhage of wounds/inability of blood to clot.