Botany and Plant Science

The remaining part of nucellus is called perisperm.

In plants only a sporophyte produces spores.

The secondary nucleus of angiosperm after fertilization is 3x. The second sperm cell fuses with both central cell nuclei, producing a triploid (3x) cell. As the zygote develops into an embryo, the triploid cell develops into the endosperm, which serves as the embryo's food supply.

In angiosperms, the embryo sac represents female gametophyte.

The ovule can be compared to megasporangium.

After fertilization, fruit is derived from ovary.

Hydathodes are special pore bearing structures present on the margin of the leaf to allow guttation.

The pollen grains mature inside the ovule and produce sperm cells.

Arils are found in yews and related conifers. Aril is a specialised outgrowth from seed that partially or completely covers the seed.

The term microsporophyll is used in gymnosperms to denote male cones.

The reduction division takes place in Megasporangium, which divides to form 4 megaspores.

The seed coat, in case of gymnosperms, is derived from female sporophyte.

Vascular cambium is a secondary meristem tissue that produces secondary xylem (wood) and phloem (inner bark), resulting in growth in circumference or girth (B), not length. Length/height growth occurs through apical meristems at shoot and root tips (primary growth). The distinction between primary (length) and secondary (circumference) growth is fundamental to understanding plant development.

A flower is a modified shoot because it develops from the shoot apical meristem and follows the same basic pattern of growth and differentiation as stems. The floral organs (sepals, petals, stamens, carpels) are all modified leaves that arise from the flanks of the floral meristem, just as leaves arise from the vegetative shoot meristem. This fundamental concept explains why flowers have whorled arrangements and why floral parts can sometimes revert to leaf-like structures (phyllody).

The stigma is the upper part of the pistil (carpel) that is specifically adapted to receive and trap pollen grains during pollination. It is often sticky or hairy to effectively capture pollen, and its surface chemistry allows compatible pollen grains to germinate and grow pollen tubes toward the ovary. The anther produces pollen (male part), while the style and ovary are involved in pollen tube growth and ovule reception, not the initial pollen capture.