Reproduction in Flowering Plants

Mr. Stuart

Living Environment

WALT – Explain how plants reproduce Sexually

•  Identify and draw, using a hand lens if necessary, the

• sepals, • petals, • stamens, • anthers, carpels, • ovaries and • stigmas of one, locally available, named, insect-

pollinated, dicotyledonous flower,

Sexual Reproduction

• Using the gametes from 2 parents to produce genetically unique individuals

Flower• Sexual reproductive structure

• Produces egg and sperm

• Fertilization takes place inside the flower

Which is the most accurate statement? The principal role of a flower in the life cycle of a plant is: • (a) attracting insects • (b) producing seeds • (c) producing pollen • (d) producing nectar

Pistil/ Carpel*Stigma –top of the carpel,Sticky surface for pollen to

stick to*Style – connects the stigma

to the ovary*Ovary –contains ovules ( eggs)

Stamen*Anther – produces sperm

nuclei by meiosis. Sperm nuclei are enclosed by pollen grains.

*Filament – holds the anther up

Female reproductive organ

Male reproductive organ

• Female • Male

Pistel = many Carpels

1) What features of flowers might attract insects?2) Which part of the flowers become a the seed and be the fruit?

Draw an accurate diagram of a flower and include both Male/

Female Organs• Pg 67

http://www.bbc.co.uk/bitesize/standard/biology/world_of_plants/growing_plants/revision/4/

Pollination

PollinationWALT –

• Explain the Transfer of mature pollen grains from the anther to the stigma using

-wind-insects-birds & other animals

• Name the agents of pollination• Compare the different structural adaptations

of• insect-pollinated and wind-pollinated flowers• Describe the growth of the pollen tube and

its entry into the ovule followed by fertilisation (production of endosperm and details of development are not required)

• and examine the pollen grains under a light microscope or in photomicrographs

• Pollination as the transfer of pollen grains from the male part of the plant (anther of stamen) to the female part of the plant (stigma)

Draw in your books• Cross Pollination

*Self pollination –pollen from same flower

*Cross pollination – pollen from a different flower - more variation

Because nature doesn’t like self pollination, often it is rejected

• When a pollen grain lands on the stigma, it sticks and a pollen tube grows down through the style to an ovule (egg)

Wind v Insect Pollination• Wind pollinated flowers are different in structure from insect pollinated

ones. • [You need to be able to explain the main differences. This table will help to

make these clear for you]

Insect pollinated flowers - rose sweet pea

Wind pollinated flowers - ragweed

Insect Pollinated Wind Pollinated

Insect Pollinated Wind Pollinated

Use the information on pg 21-22 –

Wind Pollinated Plants to help you fill

the table in

Insect Pollinated Wind Pollinated

large, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

Insect Pollinated Wind Pollinatedlarge, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

often sweetly scented - to attract insects

no scent - no need to attract insects

Insect Pollinated Wind Pollinated

large, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

often sweetly scented - to attract insects no scent - no need to attract insects

usually contain nectar - to attract insects no nectar - no need to attract insects

moderate quantity of pollen - less wastage than with wind pollination

pollen produced in great quantities - because most does not reach another flower

Insect Pollinated Wind Pollinated

large, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

often sweetly scented - to attract insects no scent - no need to attract insects

usually contain nectar - to attract insects no nectar - no need to attract insects

moderate quantity of pollen - less wastage than with wind pollination

pollen produced in great quantities - because most does not reach another flower

pollen often sticky or spiky - to stick to insects

pollen very light and smooth - so it can be blown in the wind and stops it clumping together

Insect Pollinated Wind Pollinated

large, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

often sweetly scented - to attract insects no scent - no need to attract insects

usually contain nectar - to attract insects no nectar - no need to attract insects

moderate quantity of pollen - less wastage than with wind pollination

pollen produced in great quantities - because most does not reach another flower

pollen often sticky or spiky - to stick to insects

pollen very light and smooth - so it can be blown in the wind and stops it clumping together

anthers firm and inside flower - to brush against insects

anthers loosely attached and dangle out - to release pollen into the wind

Insect Pollinated Wind Pollinated

large, brightly coloured petals - to attract insects

small petals, often brown or dull green - no need to attract insects

often sweetly scented - to attract insects no scent - no need to attract insects

usually contain nectar - to attract insects no nectar - no need to attract insects

moderate quantity of pollen - less wastage than with wind pollination

pollen produced in great quantities - because most does not reach another flower

pollen often sticky or spiky - to stick to insects

pollen very light and smooth - so it can be blown in the wind and stops it clumping together

anthers firm and inside flower - to brush against insects

anthers loosely attached and dangle out - to release pollen into the wind

stigma inside the flower - so that the insect brushes against it

stigma hangs outside the flower - to catch the drifting pollen

Fertilization• The sperm travels through the pollen tube to the

ovule. The sperm & egg fuse forming the zygote (fertilized egg) –this grows into the plant embryo (cells grow by mitosis)

• The ovary and zygote (fertilized ovule) develop and ripen.

*The ovule forms the seed and the ovary forms the fruit.

• A fruit is a ripened ovary

Germnination

WALT – Understand the process of germination

The plant embryo uses food stored in the cotyledon of the seed until it develops

leaves for photosynthesis

• Cotyledon – Leaf inside seed that supplies food to growing embryo

micropyle –opening in ovule where pollen tube attached and sperm entered

hilum –scar where ovule attached to ovary

radicle –embryonic root

Seedling

Epicotyl – grows above the cotyledons and gives rise to the leaves.

Hypocotyl –below the point of attachment of the cotyledon, develops into the stem.

Parts of a seed

• Dicot

• Monocot

Seed coat

Epicotyl

Cotyledons

Hypocotyl

Seed coatEndosperm

Epicotyl

Hypocotyl

RadicleCotyledon

Seed Germination

Monocot Dicot

Hypogeous

Epigeous

Radicle

Page 71 72 74 76

Question 1 2 5 1 2 3 4 5 1 2 3 1 2 3 4 5

Marks 1 1 1 2 1 2 3 3 1 1 1 3 2 1 1 1

This powerpoint was kindly donated towww.worldofteaching.com

http://www.worldofteaching.comIs home to well over a thousand powerpoints submitted by teachers. This a free site. Please visit and I hope it will help in your teaching