2018 - WAEC Biology Past Questions and Answers - page 2

Germinating seeds respire by using oxygen and producing carbon dioxide gas, they respire in the similar way as animals.

Animals take in oxygen in respiratory process, taking out carbondioxide. 

Homeostasis is a living organism's way of maintaining a stable internal environment even in the event of external environmental changes. When the plant keeps supplying phosphorus to the phloem even in the case of a deficiency in the soil, it maintains a steady balance on its inside irrespective of the lack in the soil.

The fine structure of the glomerulus and Bowman’s capsule facilitate ultrafiltration. It is the non-specific filtration of the blood under high pressure and occurs in the Bowman’s capsule of the nephron.

The thyroid gland is an endocrine gland located at the base of the neck.

Each neuron has a threshold that must be met before an action potential travels the length of the neurons axon. In other words, the neurons don't just begin to act immediately, there is a threshold value where the intensity of the stimulus must get to in order to yield a response from the neuron. This is why you can consciously pinch your self and not feel anything serious but when it is unconscious, it gives you serious pain.

Contact lenses have a way of causing infections to the eyes at some point. It can cause a lack of oxygen since they are worn directly in the eye, especially if worn for long periods at a stretch.

Breathing roots, also known as pneumatophores, have portions of the root which grow upward until they project some centimetres above the low-tide level. They have small openings called lenticels in their bark so that air can reach the rest of the plant’s root system.

From the diagram, the larva is a caterpillar, hence, the adult is called a Butterfly.

The diagram is the life cycle of a butterfly whose larva is called Caterpillar.