9.3-4

Indeterminate growth in plants

Growth of the shoot

Auxin and phototropism

Structure of flowers

Pollination

Seed structure

Seed germination

Plants have regions where small undifferentiated cells called meristems continue to divide and grow.

Flowering meristems have plants at the tip of the root and at the tip of the stem

These are known as apical meristems

The shoot of the plant is the stem together with the leaves

Cells in the shoot apical meristem carry out mitosis and cell division repeatedly to generate the cells needed for extension of the stem and development of leaves

Some of the cells always remain in the meristem and go on in the cell cycle to produce more cells

This production of new cells causes other cells to be displaced to the edge of the meristem

Cells at the edge of the meristem stop dividing and differentiate to become either stem or leaf tissue

Auxin is a main hormone which acts as a growth promoter, one of its processes is phototropism

Tube containing ovary stigma -> style

Anther -> filament

Sepal around flower

Petals

Before fertilization, pollination occurs, in which pollen is transferred from an anther to a stigma. Pollen grains contain male gametes, most plants use either wind or animal pollination.

Outer coat (testa)

Inner hole for water to flow in (micropyle)

Cotyledon (mono or di)

Embryo shoot (plumule)

Embryo root (radicle)

Water is absorbed through the micropyle

Synthesis of giberellins (hormones

Giberellins cause synthesis of amylase, which will hydrolyse stored starch to maltose

Maltose is absorbed by the plumule and radicle, and further hydrolysis breaks down maltose to glucose which is used for respiration