Correct Answer: C. a composite fruit

Explanation

(a) (i)Metamorphosis;refers to series of changes of forms or shapes from the fertilized egg (immature stage) to adult (mature stage or adulthood).

(ii) Two types of metamorphosis are:Complete metamorphosis, e.g, Butterfly, Housefly, Bees, Wasp, Beetles, Mosquito and Incomplete metamorphosis, e.g, Grasshoppers, Cockroach, Dragonfly , Locust, Aphids, Termites, Praying mantis

(b) (i) Economic importance of insects are:

(1) Act as carriers, vectors or transmitters of diseases ( e.g anopheles mosquito, tsetsefly etc

(2) Act as pests and are destructive to life plants or stored food (e.g locust; grasshoppers weevil, crickets)

(3) As food or source of protein (e.g termites, honey, larval forms of some beetles, cricket, grasshopper)

(4) Life processes involved in meiosis used in biological control (e.g lady bird - used in control of aphids on plantations, praying mantis:- control of some insects)

(5) Serve as pollinating agents of flowering plants (e.g bees, butterflies, ants, moths, wasps, beetles).

(6) Soil insects for aeration or loosening of soil (e.g termites, crickets, dung - beetles).

(7) Insects as industrial material, (bee wax for candles, silk worms).

(8) Termitarium used in building lawn tennis courts

(9) Revenue yielding - e.g termites, larva of beetles e.t.c.

(10) Destroy furniture, books, clothes, wood e.t.c, e.g cockroaches and termites.

(ii) Peculiar features of social insects are:

(1) They live together or form colonies

(2) They live in nests.

(3) Show or display division of labour.

(4) Show distinct castes.

(5) Members communicate with one another within the colonies.

Correct Answer: B. holozoic

Correct Answer: D. nuptial pad

Correct Answer: A. Sexual reproduction

Explanation

Sexual reproduction involves the fusion of gametes from two parents, typically a male and a female. In this process, specialized cells called gametes (sperm and egg) are produced through meiosis. The fusion of these gametes during fertilization leads to the formation of a zygote, which develops into a new individual with a combination of genetic traits from both parents.

Correct Answer: C) Transpiration

Explanation

Excessive loss of water in plants is known as transpiration. Transpiration is the process in which water evaporates from the leaves of plants and exits through small pores called stomata. This process helps plants to absorb nutrients from the soil and distribute them throughout the plant. Transpiration is an important process in plant growth and survival, but excessive loss of water can lead to dehydration and wilting. Osmosis is the movement of water molecules from an area of high concentration to an area of low concentration through a semi-permeable membrane. Osmoregulation is the process by which living organisms maintain the balance of water and salt concentrations in their bodies. Excretion is the process of removing waste products from the body. None of these options describe excessive loss of water in plants, which is why the correct answer is transpiration. Understanding transpiration is important for students studying photosynthesis and plant biology. Plants need to maintain a balance between water loss and nutrient absorption, and transpiration plays a key role in this process. To learn more about this, please read the relevant sections of the recommended textbooks.

Correct Answer: A. Water, carbondioxide and energy

Explanation

(a)(i) Excretory organs found in living organisms: Lung, kidney, skin, liver and nephridia

(ii) Lungs - man, Kidney - man, Skin - man, Liver - man, Nephridia - earth worm, Contractile vacuole - paramecium, Stomata / Lenticel - plants, Flame cells - tape worm, Malpigian tubules - insects.

(b)(1) Two ways in which the excretory organ of earth worm is similar to that of mammals are:

(1) Both possess structure for filtering excretory products.

(2) Each is well supplied with blood.

(ii) Differences between mammals and earth worm:

(c) Mechanism of opening and closing of the stomata:Each stoma is enclosed by guard cells. Guard cell has chloroplast and is also elastic. During photosynthesis, sugar is formed and this increases the concentration of cell. sap. Guard cell receives water by means of osmosis and becomes turgid. This makes the stoma to open. During the night, sugar in the guard cell is converted to starch. This makes the osmotic concentration of guard cell to reduce. Water is lost lay the guard cells through osmosis to the surrounding. This makes the guard cell to be flaccid, hence stoma closes.

Explanation

(a) Process of conversion of food to chyme in the stomach of a mammal

The stomach is a large thick-walled muscular sac; made of three layers of muscles; that contracts in different directions when food enters into it; bringing about a twisting/squeezing/churning effect; enabling food to mix with digestive juice; and HCL; this movement then converts food to the semi-liquid called chyme.

(b)Table

(c) Experiment to show that carbon dioxide is necessary for photosynthesis

Two potted plants are de-starched by placing them in a dark cupboard for 24hours;

a leaf each from both plants are then tested for starch to ensure they have no starch/have been de-starched; the potted plants are placed on a board each; a beaker containing caustic soda is placed beside plant A; to absorb carbon dioxide; while a beaker containing water is placed beside plant B as control; they are both covered with bell jars labelled A and B respectively; the rim/edge is smeared with vaseline/petroleum jelly to make it air tight; the setup is exposed to sunlight/light for 4-6 hours; a leaf each from both plants are plucked and tested for starch.

Observation:It is observed that leaf from plant A is negative/does not contain starch/remains brown in colour while leaf from plant B is positive/contains starch/turns blue - black.

Conclusion: Carbon dioxide is necessary for photosynthesis.

OR

De-starch a well-watered potted plant by putting it in darkness for 48 hours; insert a leaf into a flask containing water which serves as a control experiment; and another leaf into another flask containing KOH/ potassium hydroxide/ caustic potash; ensure both flasks are air tight by smearing the split corks with Vaseline; leave the potted plant in a well-lit place for

Correct Answer: D. presence of network of capillaries around the convoluted tubules