JAMB Biology Past Questions & Answers - Page 83

Butter is about 80% fat, and the rest is mostly water and each gram of fat provides twice as much energy as carbohydrates or proteins. It is very high in saturated (about 70%) fatty acids, and contains a fair amount of monounsaturated fatty acids (about 25%).

The most abundant chemical in meat is water, followed by protein, then fat. Carbohydrates, minerals, and vitamins occur in much smaller amounts but, nevertheless, are very important metabolically and nutritionally.

Special temporary organs or embryonic membranes form within the egg, both to protect the embryo and to provide for its nutrition, respiration, and excretion. These organs include the yolk sac.

The yolk sac is also responsible for the initial circulation and is in charge of delivering nutrients, via a primitive aorta, to the developing embryo through a process called vitelline circulation.

Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several pro-vitamin A carotenoids (most notably beta-carotene). Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system and good vision.

Maltose is composed of two molecules of glucose.

An animal with radial symmetry really has no right and left side or head and rear end. This animals do not move, so they can reach into their environment from all sides. Starfish is an example of a radial symmetrical organism. They can be attached to a substrate, like the sea anemone, or float, like jellyfish. It also occurs in simple animals including the aquatic cnidarians, which include hydra, corals, jellyfish and sea anemones, and Ctenophora, which are comb jellies.

One of the common traits amongst the cnidarians is their symmetry. Hydras, like all cnidarians, display radial symmetry.