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Nature^93

SEEDS

If fertilization occurs in a flowering plant, a seed forms inside the

flower’s ovary. The seed consists of a tiny embryo plant, a

food store for the embryo, and a protective coat.

WHAT IS GERMINATION?

The first growth stage of an embryo plant from a

seed is called germination. When there is enough

sunlight and water, the seed germinates (sprouts), and

the embryo plant starts to grow. Until it develops

leaves, the seedling depends on the seed’s food store.

WHAT IS A FRUIT?

As the seeds of plants develop, the ovary surrounding

the seed develops into a fruit, such as a tomato or a

peapod. Fruits protect seeds, and help disperse them

away from the parent plant so that new plants

have enough water and light to grow.

1 SEED DISPERSAL IN FRUIT
The seeds of juicy fruits, such as raspberries, are dispersed
in droppings of fruit-eating animals. The seeds of dry
fruits, such as love-in-the-mist, are spread by wind, by
sticking to animal coats, or by the fruit bursting open.

BEAN SEEDLING 3

Just a few days after germination, the

bean seedling’s roots have grown down

into the soil, and its shoot has grown

upwards towards the Sun.

First leaves

make food using

sunlight energy

Roots

take in water

and minerals

from the soil

4 WIND DISPERSAL

Dandelion seeds hang from

parachute-like fruit. When blown

by the wind, the parachutes float

off into the air and carry the seeds

far from the parent plant.

RASPBERRY LOVE-IN-A-MIST

WHAT IS WIND POLLINATION?

Pollination in some flowers occurs when pollen is

blown from other flowers by the wind. Animal-

pollinated flowers, are strongly scented and brightly

coloured, but the flowers of wind-pollinated plants,

such as grasses, are often small, with no petals.

WHAT IS NECTAR?

Many flowers attract pollinating

animals with a sweet, sugary liquid

called nectar. If an animal feeds on

the nectar, it picks up pollen and

carries it to other flowers that it lands on.

4 POLLEN GRAIN

The spikes on this pollen grain help it stick to animals. Each

grain contains the male sex cell, which fertilizes the female ovum.

1 INSECT POLLINATION
Yellow pollen sticks to this bee’s legs as it feeds on
nectar. It will be passed to the next flower it visits.

Seed

POLLINATION

The transfer of pollen from a male anther to a female stigma is

called pollination. If male and female sex cells from the same

species come together, fertilization takes place and seeds are made.

Pollination occurs in various ways, such as by wind or by animals.

Ovary

Ovum

(female

sex cell)

Pollen tube

Ovule

Male

nucleus

FERTILIZATION

When a pollen grain lands on a

stigma of the same species, it

grows a tube into the ovule (seed-

forming structure). A male sex cell

travels down the pollen tube and

fertilizes the ovum (female sex

cell) to produce an embryo plant.

Stigma Pollen

Style

FIND OUT MORE. Life on Earth 70–71 • Non Flowering Plants 90–91 • Plants 88–89 • Trees 94–95