JAMB Biology Past Questions & Answers - Page 46

Wind-pollinated flowers:

• No bright colors, special odors, or nectar.
• Small.
• Most have no petals.
• Stamens and stigmas exposed to air currents.
• Large amount of pollen.
• Pollen smooth, light, easily airborne.
• Stigma feathery to catch pollen from wind.

Vascular tissue is comprised of the xylem and the phloem, the main transport systems of plants.

The xylem is the plant vascular tissue that conveys water and dissolved minerals from the roots to the rest of the plant and also provides physical support.

A flame cell is a specialized excretory cell found in the simplest freshwater invertebrates, including flatworms (fluke, planaria)

Flame cells function like a kidney, removing waste materials.
Excretion of ammonia waste through the body wall, and is not associated with any specific organs.

A coccus (plural cocci) is any bacterium that has a spherical, ovoid, or generally round shape. A bacillus is any bacterium that has a rod shape.

Vibrio is bacteria possessing a curved-rod shape

Diplobacillus is a rod-shaped bacterium occurring in pairs linked end to end.

Nucleus is a specialized structure occurring in most cells (except bacteria and blue-green algae) and separated from the rest of the cell by a double layer, the nuclear membrane. This membrane seems to be continuous with the endoplasmic reticulum (a membranous network) of the cell and has pores, which probably permit the entrance of large molecules. The nucleus controls and regulates the activities of the cell (e.g., growth and metabolism) and carries the genes, structures that contain the hereditary information.