Protoplasm

Protoplasm [ Biology ]

Dictionary of botanic terminology - index of names

The viscous translucent material that makes up the substance of all living cells.

Fundamental material composing all living things. Protoplasm which exists in all plants and animals in the small units called cells, is mainly (85-90 percent) water and also contains proteins, fatty substances and inorganic salts including enzymes and organized particles which carry out specific functions within the cell. It is always enclosed by a thin surface membrane that controls the passage of materials into and out of the cell. It displays the general properties associated with life-the capacity to respond to stimuli and the ability to perform the essential physiological functions. In the plants it represent the living portion of a cell as opposed to the non-living cell wall.

Advertising

Holdfast roots [ Botany ]
Dictionary of botanic terminology - index of names

Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.

Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans), develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994