Correct Answer: C. Volvox

Correct Answer: D. Placing a lighted electric bulb over soil in a funnel

Correct Answer: B. attract pollinators

Correct Answer: B. clayey

Correct Answer: C. Eustachian tube

Explanation

(a)(i) Description of Epigeal Germination:

(i) Seed absorbs/imbibes water and swells.

(ii) Testa splits and the radicle emerges.

(iii) The hypocotyl of the germinating seed elongates.

(iv) Pushing the seed out of the soil.

(v) The cotyledon(s) become exposed to sunlight.

(vi) Turns green to photosynthesize.

(vii) The plumule develops into a green shoot.

(viii) The cotyledon(s) dry up/shrink and fall off.

(ii) Differences between epigeal and hypogeal germination:

(b)(i) Seed dormancy: An inactive period of a seed.. During which growth slows/completely ceases. Due to certain internal or external factors.

(ii)Ways of breaking dormancy:Removal/corrosion of testa. Treatment of seed with acid/digestive enzymes/water. Exposure to alternating high and low temperature. Addition of dormancy-breaking hormones/named hormones. Exposure to fire. Exposure to light.

(c) Advantages of using contraceptives in human population:

(i) It controls birth rate.

(ii) Reduces over-population.

(iii) Promotes maternal health/reduces maternal death.

(iv) Promotes infant survival rate.

(v) Enables parents to determine family size.

(vi) Prevents unwanted pregnancy.

(vii) Enhances good standard of living for the family.

(viii) Some prevent STI or STDs.

Explanation

(a) Classes of food other than carbohydrates are: protein, fats and oils / lipids, water, vitamins, mineral salts.

(b) The reasons why glucose is taken by an athlete before a race are: glucose is the simplest form of carbohydrate, i.e. soluble form of cabohydrate; which does not require any form of digestion. Hence, it is absorbed in the ileum, small intestine, where it diffuses and enters into the blood stream, circulatory system. It is then assimilated and oxidized; within the shortest time to give energy to the athlete. But corn meal is a complex carbohydrate, polysaccharide, starch, which will require series of carbohydrate / hyrolysis, starting from the mouth and later in the duodenum. Due to the processes, carbohydrate has to pass through it to the small intestine, ileum, which takes a longer time to produce energy for use, i.e cannot give immediate energy.

(c) To test for starch, obtain tuber of yam, cassava, potato, sweet potato, maize, cereal or any starchy food and macerate (crush). Then, add water to the mash to prepare starch solution; put a few drops of the starch (mashed material or a bit of the macerate on a white tile) test tube or watch glass. Add one to two drops of iodine and the material or solution will turn blue black, or black indicating presence of starch.

Correct Answer: A) thick barks, succulent stems and sunken stomata

Explanation

Plants that live in the desert environment face unique challenges such as high temperatures, low water availability, and high salinity. These conditions have led to the development of adaptive features that help them survive. One of these adaptive features is having thick barks, succulent stems, and sunken stomata, which is the correct answer to the question. Thick barks provide insulation for the plant against the high temperatures, while succulent stems store water for the plant during prolonged periods of drought. Sunken stomata help to reduce water loss by keeping the stomata below the surface of the leaf, where it is cooler and less windy. Option B on the other hand, thin barks, succulent stems, and sunken stomata, is incorrect because plants with thin barks would not be able to withstand the harsh desert environment as it will not provide enough insulation for the plant. Option C, thin barks, air floats on stems, and sunken stomata, is also incorrect because while air floats on stems can help with buoyancy, it does not help with the plant's survival in the desert environment. Option D, air spaces on tissues, adventitious roots, and thin barks, is incorrect because air spaces on tissues do not provide any benefits to the plant in the desert environment, and adventitious roots are not an adaptive feature of plants in the desert environment. In summary, the adaptive features of plants in the desert environment include thick barks, succulent stems, and sunken stomata to help them survive in the harsh conditions of the desert.

Correct Answer: B) food chain

Explanation

In this question, we are being asked to identify which of the following options does not contribute to the biomass in an ecosystem. Biomass is the total mass of living organisms in a particular area or ecosystem. The options we are given are: producer's, food chain, consumer's, and micro-organisms. Out of these options, we need to choose the one that does not contribute to the biomass in an ecosystem. Option A, which is producer's, contributes to the biomass in an ecosystem. Producers are organisms that can produce their own food using sunlight, water, and carbon dioxide. They form the base of the food chain and support the entire ecosystem. Therefore, option A is not the correct answer. Option C, which is consumer's, also contributes to the biomass in an ecosystem. Consumers are organisms that consume other organisms for food. They can be herbivores, carnivores, or omnivores. Their biomass contributes to the total biomass of the ecosystem. Therefore, option C is not the correct answer. Option D, which is micro-organisms, also contribute to the biomass in an ecosystem. Micro-organisms are tiny organisms that are not visible to the naked eye. They play important roles in nutrient cycling and decomposition. Their biomass contributes to the total biomass of the ecosystem. Therefore, option D is not the correct answer. Option B, which is food chain, is the correct answer. Food chain is a series of organisms in which each organism is eaten by the next organism in the chain. Food chains do not contribute to the biomass in an ecosystem because they do not represent the total mass of living organisms in the ecosystem. Rather, they represent the flow of energy and nutrients through the ecosystem. In conclusion, option B, which is food chain, does not contribute to the biomass in an ecosystem.

Correct Answer: A. Virus