Botany and Plant Science

Wilting refers to the loss of rigidity of non-woody parts of plants. This occurs when the turgor pressure in non-lignified plant cells falls towards zero, as a result of diminished water in the cells. Wilting occurs by blocked xylem as xylem carries water in plants.

Endosperm is the tissue produced in the seeds of most flowering plants around the time of fertilisation. It is triploid in nature.

Adventitious roots arise from an organ other than the root; usually a stem, or sometimes a leaf. They are especially numerous on underground stems. It arises from plumule.

It is a soft plant tissue containing air spaces, found especially in many aquatic plants.

Circinate vernation is the manner in which a fern frond emerges. As the fern frond is formed, it is tightly curled so that the tender growing tip of the frond (and each subdivision of the frond) is protected within a coil.

A flower head or capitulum is a very contracted raceme in which the single sessile flowers are borne on an enlarged stem. 

Brassica has six stamens, four of which are longer than the others.

Circinate vernation is the manner in which a fern frond emerges. As the fern frond is formed, it is tightly curled so that the tender growing tip of the frond (and each subdivision of the frond) is protected within a coil.

Xenia in plants is the effect of pollen on seeds and fruit of the fertilised plant. The effect is different from the contribution of the pollen towards the next generation. The effect, such as an increase in size, on the embryo or endosperm of a plant results from fertilisation with pollen of a genetically distinct variety.

Tree rings grow under the bark and the bark is pushed out while the tree is growing. The inner part of a growth ring is formed early in the growing season, when growth is fast, and is known as early wood. The outer portion is the late wood, and is denser than early wood. This is formed by the activity of intrastelar cambium and interstelar cambium.

Stamens are fused together, at least partly, by the filaments so that they form two separate bundles. This is the characteristic of family Fabaceae.

Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapour and is released to the atmosphere. It is essentially evaporation of water from plant leaves. Thus, humidity decreases the rate of transpiration.

Angiosperms form fruit. Gymnosperms, being the naked seeded trees, do not form a fruit.

Sieve tubes are connected with perforated sieve plates. They help in the conduction of food downhill.

A meristem is the tissue in most plants that contains undifferentiated cells (meristematic cells). It is found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of the plant and keep the plant growing.