Waec 2019 Biology Obj And Theory Answers – May/June Expo

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Biology OBJ:
1CBABBDBDCB
11DDCAABAABD
21CCCAAACDDB
31DBADDAACDD
41ACDDABDCDB

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(3a)
TABULATE
Under PARASITISM:
-Mistletoe and cacao plant.
-Tapeworm in the gut of humans.
-Lichen
Under MUTUALISM:
-Cattle and white egret.
-Flowers and honeybee
Under COMMENSALISM:
-Remora and shark.

(3bi)
(i) They have strong suckers and hooks.
(ii) They have large surface area for absorptions of nutrients.
(iii) They have thin and flattened shape.
(3bii)
[Pick any Two] (i) They have blood loss.
(ii) They cause diarrhoea.
(iii) They cause severe loss of weight.

(3ci)
Saprophytes are mainly non-green plants which do not have chloroplasts and therefore cannot manufacture their own food.
(3cii)
[Pick any Four] (i) Rhizopus
(ii) Mushroom
(iii) Mucor.
(iv) Agaricus
(v) Yeast

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(1ai)
TABULATE:
ORAGNISM |RESPIRATORY SURFACE
Tadpole |Skin
Cockroach|Trachea
Domestic fowl|Lungs
Talinum |Stomata
Earthworm|Skin
Amoeba |Cell membrane

(1b)
(i) Large surface area
(ii) Thin respiratory surface
(iii) Moist surface
(iv) Efficient transport system.
(v) Permeability

(1c)
Draw

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(2a)
(i) Meat type A and meat type D
(ii) they contain the lowest fat content

(2bi)
(i)Meat type C and meat type D
(ii)
– Proteins gives energy
– Strengthens muscle

(2ci)
(i) A, C & D
(ii) A person deficient in protein suffers kwashiokor. Hence a diet with high content in protein is needed.

(2di)
Meat type D
ii) Meat type F

(2e)
carbohydrates

(2f)
– For energy and heat to keep the body warm
– Are used as insulators to nerves and cell membranes
– Formation of cell membranes

(2g)
Drop the meat on a white paper observe the meat against a source of light, the far part becomes more translucent
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(6ai)
The enormous energy of lightning breaks nitrogen molecules and enables their atoms to combine with oxygen in the air forming nitrogen oxides. These dissolve in rain, forming nitrates, that are carried to the earth.

(6aii)
This organism oxidizes ammonia into nitrite as a metabolic process. Nitrosomonas are useful in bioremediation. They are important in the nitrogen cycle by increasing the availability of nitrogen to plants while limiting carbon dioxide fixation.

(6aiii)
Azotobacter helps to synthesizes some biologically active substances, including some phytohormones such as auxins, thereby stimulating plant growth.

(6b)
(i) Malphigan tubule
(ii) Nephridium

(6c)
(i) Hepatitis: This is a liver disease defined as inflammation of the liver. It may occur as a result of viral infection or toxic substances like poisons or drugs. This disease makes the liver unable to perform it’s functions properly.

(ii) Kidney stones: This is caused by diseased growth in the kidneys within the tubules. This growth narrows rye tubules preventing free flow of urine. It most causes complete blockage of. Urine results.

(6di)
(i) It makes the system insensitive.
(ii) It Mars the protective role of the system.
(iii) Temperature will be poorly regulated.

(6dii)
(i)Cornified layer.
(ii)Granular layer.
(iii)Malphigean layer.

(6ei)
Metamorphosis is the series of gradual changes of forms and shape of insect from the fertilized egg to adult.

(6eii)
Grasshopper – Incomplete
Cockroach – Incomplete
Butterfly – complete
Mosquito – complete
Housefly – complete

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