Botany and Plant Science

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Lateral meristems (vascular cambium and cork cambium) are responsible for secondary growth, which increases the girth/thickness of stems and roots. Apical meristem causes primary growth (length increase). Intercalary meristem causes growth at nodes (seen in grasses). Only lateral meristem produces secondary growth.

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The pollen grains having a single furrow are known as monocolpate.The pollen grains of monocots also differ from those of most dicots. In monocots, each pollen grain has just one thin-walled region, the colpus, which is the area from which the pollen tube emerges when the pollen grain germinates.

Sporopollenin is a major component of the tough outer (exine) walls of spores and pollen grains. It is chemically very stable and is usually well preserved in soils and sediments.

The megasporangium is surrounded by layers of sporophyte tissue called the integument. The integument and structures within i.e.,megasporangium and megaspore are called the ovule.

In this type, the ovary is monolocular. The ovules are few or reduced to one and borne at the base of the ovary. The ovule when solitary often fills the ovary cavity e.g., sunflower.

In this type, the ovule takes a 90 degree turn so that the micropyle is at right angles to the funicle.

Ovaries are attached directly to the receptacle, but can be sunken into it superior with no stalk, or on stalk-like extensions of the receptacle, as in Isomeris arborea. The ovary surrounds one or more locules in which ovules develop from placenta.

The Rosaceae or rose family is a large family of flowering plants, Roses can be herbs, shrubs or trees. Most species are deciduous, but some are evergreen.They have a worldwide range, are the most diverse in the northern hemisphere. The flowers have superior ovaries.

If a gynoecium has multiple carpels fused into a single structure, it is syncarpous. A syncarpous gynoecium can sometimes appear very much like a monocarpous gynoecium.

It is the outermost whorl consisting of units called sepals.These are typically green and enclose the rest of the flower in the bud stage, however, they can be absent or prominent and petal-like in some species.

It is stalk or the basel barren part of a flower. A flower with pedicel is called pedicellate, e.g., Hibiscus, Caesalpinia and without pedicel is called sessile, e.g., Polianthes, disc floret of Helianthus.

It is the second whorl internal; to die calyx. It is made up of petals which are usually enlarged, delicate, bright coloured and often with sweet fragrance. Their function is to attract insects for pollination and also to protect the inner essential whorls.