Plant Reproduction

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sexual reproduction:

involves 2 gametes joining together during fertilisation

offspring have combination of parent traits(not identical to parents)

flower is reproductive part of the plant

asexual reproduction:

means that offspring is formed by only one parent

offspring are iddentical

EG.--strawberry plants produce runners. the runners produce the new plant.

Sexual reproduction

structure of the flower

carpel (not pistil)

main parts

sepals-protects the flower when in bud

petals-attract isects and protect reproductive parts

carpel-female part of the flower(produces egg)

stamen-male part of the flower(produces pollen grain)

*only left side*

except egg

female parts:

stigma-landing place for pollen grains

style-connects stigma to ovary

ovary-contains ovules

ovule-produces egg

female gamete

male parts:

pollen-male gamete

anther-produces pollen grains

filament-supports anther

pollination

pollination is transfer of pollen from stamen to carpel

methods:

wind pollination-carpel and stamen always outside petals

insect pollination-carpel and stamen inside petals,insects attracted by smell and colour of the flower,go to get nectar and pollen sticks to them,go to carpel in another plant

fertilisation

is the joining of the male and female gametes to form a zygote

pollon grain forms pollen tube down to ovary

combins with egg in ovule

after fertilisation:

ovule becomes a seed

coat called testa forms around seed

zygote forms to an embryo(young plant)

embryo cosists of radicle(future roots) and plumule(future shoot)

ovary swells with food to form a fruit which surrounds the seed

structure of the seed

seed coat:testa

food storage

embryo:-plumule(shoot) -radicle(root)

seed dispresal

its the carrying of seed/fruit as far as possible from the parent plant

benefit:seedlings dont compete for light,space,water + minerals with parent plant

methods of dispersal:

water(coconuts)

self(pea pods)

wind(sycamore)

animals-edible(berries)-sticky(goosegrass)

Germination

is the growth of a seed to form a new plant

conditions needed to germinate:

water

oxygen

suitable temperature

main events in germination:

seeds absorb water from the soil

food supply in embryo allows plumule and radicle to grow

radicle bursts out from test followed by plumule

once leaves form above soil plant begins to make its own food

experiment

set up apperatus as shown

leave for a week

see which seeds germinate

results-A does as it isnt lackind any conditions neccesary to germinate

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