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Flowering Plants. By Neil Bronks. The Parts of a Flower. Most flowers have four parts: sepals, petals, stamens, carpels. The parts of a flower. Sepals protect the bud until it opens. Petals attract insects. Stamens make pollen. Carpels grow into fruits which contain the seeds.
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Flowering Plants By Neil Bronks
The Parts of a Flower • Most flowers have four parts: • sepals, • petals, • stamens, • carpels.
The parts of a flower • Sepals protect the bud until it opens. • Petals attract insects. • Stamens make pollen. • Carpels grow into fruits which contain the seeds.
Stamen (male) • Anther: pollen grains grow in the anther. • When the grains are fully grown, the anther splits open.
Pistil (female) • Stigma • Style • Carpel (ovary) • Ovules (eggs)
Parts of a Flowering Plant Female Parts Stigma Style Ovule Ovary Together called the CARPEL Male Parts Anther Filament Together called the STAMEN
Pollination • Flowering plants use the wind, insects, bats, birds and mammals to transfer pollen from the male (stamen) part of the flower to the female (stigma) part of the flower.
Pollination • A flower is pollinated when a pollen grain lands on its stigma. • Each carpel grows into a fruit which contains the seeds.
Fertilisation • Fertilised ovules develop into seeds. • The carpel enlarges to form the flesh of the fruit and to protect the ovary.
Pollen Some of the pollen sticks on the STIGMA Pollen is produced in the ANTHER The pollen goes down a small tube to the EGG There are lots of eggs in most plant ovaries. The anther explodes and pollen just goes everywhere
Pollen Sexual reproduction is where two different cells meet Sex cells are called GAMETES The female gamete is theEGG When the pollen and egg meet this is called FERTILISATION Pollen is the male gamete
Ways to Scatter Pollen Wind Insect
Wind Scattered Pollen Petals Small and green No Scent or Nectar Anthers Outside Carry a large amount of very small pollen. Examples- Grass Oak Trees
Wind pollination • Some flowers, such as grasses, do not have brightly coloured petals and nectar to attract insects. • They do have stamens and carpels. • These flowers are pollinated by the wind.
Insect Scattered Pollen Petals Colourful Scented Contain sweet liquid called NECTAR Anthers contain a small amount of large pollen Example Roses Dandelions
Fertilisation When the male gamete POLLEN Gets inside the female gamete or EGG They form aZYGOTE This is the first cell of a new plant
Zygote • The zygote grows to form a baby plant • The first cells divide and form an EMBRYO
Zygote • The embryo starts to become a root • If the flower has lots of ovules it makes lots of seeds (Apples)
Radicle (Root) Plumule (Stem) Testa Food Supply (OIL and STARCH) The two together make the EMBRYO Seed or Fruit Formation
Zygote forms here Seeds Germination Wet and warm conditions Next the shoot grows up to the light The first leaves Embryo becomes primitive root Lateral roots form
Seed dispersal Seeds are dispersed in many different ways: • Wind • Explosion • Water • Animals • Birds
EATEN STICKY Thistles Berries Seed Dispersal The carrying of the seed (and its surrounding fruit) as far away from the parent plant as possible ANIMALS WIND Sycamore Dandelion
Fruit Wall (Pod) SELF DISPERSAL WATER DISPERSAL Pod bursts and flings seeds out A floating seed is carried by sea or river
How birds and animals help seed dispersal • Some seeds are hidden in the ground as a winter store. • Some fruits have hooks on them and cling to fur or clothes.
How birds and animals help seed dispersal • Birds and animals eat the fruits and excrete the seeds away from the parent plant.
Asexual Reproduction A plant produces another plant without involving a second plant No gamete cells are used. The plant sends out runners
