b. List five parts of the alimentary canal of an earthworm. [5 marks] c. State six ways by which water could be polluted by agricultural. [6 marks] d. Descr...

Answer Details

b. The five parts of the alimentary canal of an earthworm are the mouth, pharynx, esophagus, crop, and gizzard.

c. Six ways by which water could be polluted by agricultural activities are:

1. Runoff from fields carrying pesticides and fertilizers into nearby water bodies.
2. Livestock waste and manure runoff into rivers and streams.
3. Leaching of nutrients and chemicals from fields into groundwater.
4. Erosion from tilled fields, which can carry sediment and nutrients into waterways.
5. Irrigation runoff carrying chemicals and salts.
6. Discharge of untreated or poorly treated agricultural wastewater into surface waters.

d. The life cycle of a housefly involves four stages: egg, larva, pupa, and adult. Adult female houseflies lay eggs on organic matter such as garbage, animal waste, or decaying food. The eggs hatch into larvae, commonly known as maggots, which feed on the organic matter for several days. The larvae then move to a dry location to pupate, forming a hard outer casing known as a puparium. Within the puparium, the larvae transform into an adult fly. The adult emerges from the puparium, mate, and begin the cycle anew.

e. Hypogeal germination is a type of seed germination where the cotyledons (seed leaves) remain below the soil surface. In a mature maize seedling, the embryo is located at the base of the kernel, and the radicle (embryonic root) emerges first during germination. The radicle grows downward, elongates, and forms lateral roots. The shoot also emerges from the embryo and grows upward, carrying the plumule (embryonic shoot) and the first true leaves above the soil surface. The diagram of hypogeal germination in a mature maize seedling should show the radicle, the embryonic shoot, the first true leaves, the kernel, and the soil.