Botany and Plant Science

Epidermis is in two layers, one on each surface of the leaf. Both the epidermal layers are composed of compactly arranged, barrel shaped cells. Cuticle and trichomes are present in both the layers. Stomata are found in both the epidermal layers. This condition is described as amphistomatic. A few cells in the upper epidermis are enlarged to form motor cells called bulliform cells.

Veins represent the vascular bundles. They are found irregularly scattered in the mesophyll due to reticulate venation. The largest and the oldest vein is found in the centre. It is known as midrib vein.

When a leaf has more than one leaf blade on a stalk,  it is called as a compound leaf. The multiple leaf blades are known as leaflets. The leaflets together make a single leaf that is attached to a single stalk. Like a simple leaf, the stalk of a compound leaf is also attached to the plant body and it leaves a scar mark on the plant body when it is removed from the stem.

A bulb is part modified stem, part modified leaves. The stem portion is compressed and its central terminal bud is surrounded by fleshy modified leaves. Onions, tulips, and daffodils all produce true bulbs. Next time you cut an onion in half longitudinally, look in the centre for the terminal bud.

It is a fleshy product of a tree or plant that derives from flowers.

It is a condition in which male reproductive organ matures before female reproductive organ.

It provides nourishment to pollen grains.

It is an organic substance that can withstand extreme environment conditions.

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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.