State the structure & function of the floral parts including: Sepal, petal,stamen,carpel

State the structure & function of the floral parts including: Sepal, petal,stamen,carpel)

• State the structure & function of the floral parts including: Sepal, petal,stamen,carpel)

• State that the Pollen grain produces male gamete.

• State that the Embryo sac produces an egg cell & polar nuclei.

• Define the terms: pollination, self-pollination

• Outline methods of pollination including: cross-pollination & self pollination

Define the term: fertilisation.

• Define the term: fertilisation.

• Outline seed structure & function of following: testa, plumule, radicle, embryo, cotyledon

• Explain embryo & food supply (endosperm or seed leaves)

• Classify plants as monocotyledon or dicotyledon & distinguish between them.

• Make reference to non-endospermic seed.

• Outline fruit formation.

• Outline seedless fruit production

Outline fruit & seed dispersal and give with examples of wind/water/animal/self dispersal

• Outline fruit & seed dispersal and give with examples of wind/water/animal/self dispersal

• Explain & emphasise the need for dispersal

• Define the term dormancy.

• State advantages of dormancy.

• Explain dormancy in agricultural & horticultural practice.

• Define the term: Germination.

• Explain the factors necessary for and role of digestion and respiration in germination.

• Outline the stages of seed development

State that vegetative propagation is asexual reproduction

• State that vegetative propagation is asexual reproduction

• Give 1 example of vegetative propagation from stem, root, leaf, bud

• Compare reproduction by seed and by vegetative reproduction

• Outline 4 methods of artificial propagation in flowering plants

Sepal : To protect the flower (and to prevent it from drying out

• Sepal : To protect the flower (and to prevent it from drying out

• Petals : To attract insects to the flower for pollination

Stamen : To produce the pollen grains in the anthers. (Each pollen grain produces two male gametes, one of which can fertilise an egg cell)

• Stamen : To produce the pollen grains in the anthers. (Each pollen grain produces two male gametes, one of which can fertilise an egg cell)

Carpel : To produce the ovules (Each ovule contains an egg cell inside an embryo sac)

• Carpel : To produce the ovules (Each ovule contains an egg cell inside an embryo sac)

Transfer of pollen from the anther to the stigma of a flower of the same species

• Transfer of pollen from the anther to the stigma of a flower of the same species

Self pollination

• Self pollination

• Transfer of pollen from an anther to a stigma of the same plant

Animal Pollination

• Animal Pollination

• Wind Pollination

Petals brightly coloured, scented with nectaries

• Petals brightly coloured, scented with nectaries

• Small amounts of sticky pollen

• Anthers inside petals

• Stigmas sticky, inside petals

Petals small, not coloured brightly

• Petals small, not coloured brightly

• Anthers outside petals

• Stigmas large, feathery and outside petals

• Pollen Large numbers, light, dry and small

Fertilisation is the fusion of the male (n) and female (n) gametes to produce a zygote (2n)

• Fertilisation is the fusion of the male (n) and female (n) gametes to produce a zygote (2n)

• The pollen grain produces the male gametes

• Embryo sac produces an egg cell and polar nuclei

The pollen grain produces the male gametes

• The pollen grain produces the male gametes

• Embryo sac produces polar nuclei and an egg cell

The zygote grows repeatedly by mitosis to form an embryo

• The zygote grows repeatedly by mitosis to form an embryo

• An embryo consists of a plumule (future shoot), a radical (future root) and cotyledons (food stores needed for germination)

The endosperm nucleus (3N) divides repeatedly to form the endosperm in endospermic seeds. This endosperm acts as a food store for the developing seed

• The endosperm nucleus (3N) divides repeatedly to form the endosperm in endospermic seeds. This endosperm acts as a food store for the developing seed

• e.g. maize

In non-endospermic seeds the endosperm is used up in the early stages of seed development so the food is stored in the cotyledons

• In non-endospermic seeds the endosperm is used up in the early stages of seed development so the food is stored in the cotyledons

• e.g. bean

Classified according to two features:

• Classified according to two features:

• Number of cotyledons (Seed leaves)

• Monocotyledon – one cotyledon
• E.g. Maize
• Dicotyledon - Two cotyledons
• E.g. Broad bean

• Presence of endosperm

• Present – Endospermic e.g. maize
• Absent – Non-endospermic e.g. broad bean

The ovule becomes the seed

• The ovule becomes the seed

• The ovary becomes the fruit

A fruit is a mature ovary that may contain seeds

• A fruit is a mature ovary that may contain seeds

• The process of fruit formation is stimulated by growth regulators produced by the seeds

Can be formed in two ways

• Can be formed in two ways

• Genetically

• Either naturally or by special breeding programmes

• e.g. seedless oranges

Growth regulators e.g. auxins

• Growth regulators e.g. auxins

• If large amounts of growth regulators are sprayed on flowers fruits may form without fertilisation
• e.g. seedless grapes

Need for dispersal

• Need for dispersal

• Minimises competition for light, water etc.
• Avoids overcrowding
• Colonises new areas
• Increases chances of survival

Wind

• Wind

• Water

• Animal

• Self

Wind

• Wind

• Sycamore and ash produce fruit with wings
• Dandelions and thistles produce fruit with parachute devices
• Both help the disperse the seeds more widely using wind

Water

• Water

• Light, air filled fruits that float away on water

• E.g. coconuts, water lilies

Animal

• Animal

• Edible fruit
• Animals attracted to bright colours, smells and food
• Seed passes through digestive system unharmed
• E.g. strawberries, blackberries, nuts

Animal

• Animal

• Sticky fruit
• Fruits with hooks that can cling to the hair of an animal and be carried away
• E.g. burdock, goose grass

Self

• Self

• Some fruits explode open when they dry out and flick the seed away
• E.g. peas and beans

A resting period when seeds undergo no growth and have reduced cell activity or metabolism

• A resting period when seeds undergo no growth and have reduced cell activity or metabolism

Plant avoids harsh winter conditions

• Plant avoids harsh winter conditions

• Gives the embryo time to develop

• Provides time for dispersal

Some seeds need a period of cold before they germinate

• Some seeds need a period of cold before they germinate

• It may be necessary to break dormancy in some seeds before they are planted for agricultural or horticultural purposes

• This can be done by placing them in the fridge before they are planted

The re-growth of the embryo after a period of dormancy, if the environmental conditions are suitable

• The re-growth of the embryo after a period of dormancy, if the environmental conditions are suitable

Water

• Water

• Oxygen

• Suitable temperature

• Dormancy must be complete

Water

• Water

• Activates the enzymes
• Medium for germination reactions e.g. digestion
• Transport medium for digested products

Oxygen

• Oxygen

• Needed for aerobic respiration

Digestion

• Digestion

• Of stored food in endosperm and cotyledon

• Respiration

• To produce ATP to drive cell division

• Events in germination cease when the plants leaves have developed and the plant has started to photosynthesise

Water is absorbed

• Water is absorbed

• Food reserves are digested

• Digested food is moved to the embryo

• New cells are produced using amino acids

• Glucose is turned into ATP to drive cell division

• Radicle breaks through the testa

• Plumule emerges above ground

• New leaves begin to photosynthesise

Outline the main stages of sexual reproduction in plants

• Outline the main stages of sexual reproduction in plants

• END