Plant Reproduction and Germination

The reproduction in phanerogams occurs by seeds. 

These have male reproductive organs in one individual and female in another like gymnosperms.

Generally, it is the seeds of the plants which are used to extract oils. For example: seeds of mustard, linseed, etc.

The slimy green patches growing on the surface of ponds are known as algae. These algae reproduce and multiply in ponds by fragmentation and turn the whole pond green.

Secondary dormancy occurs in some non-dormant and post dormant seeds that are exposed to conditions that are not favourable for germination, like high temperatures. It is caused by conditions that occur after the seeds have been dispersed.

Barochory or the plant use of gravity for dispersal is a simple means of achieving seed dispersal. The effect of gravity on heavier fruits causes them to fall from the plant when ripe. Fruits exhibiting this type of dispersal include apples, coconuts and passion fruit, and those with harder shells.

A plant bearing seeds but no fruits is pinus.

Seeds are winged in pinus.

In gymnosperms, seeds are produced in cones.

Gymnosperms differ from angiosperms in having naked ovules.

Plants produce seed that germinate before they detach from the parent plant.

These are bone-like or columnar with swollen ends. For example: Sub-epidermal covering of legume seeds.

Jute is a natural plant fiber obtained from jute plant. Harvesting of jute plant is done at the flowering stage. Its stem is then immersed in water for the easy separation of jute fibers.

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