Bio - 3.a reproduction in plants

how do fungi reproduce

budding - asexual

how do bacteria reproduce

binary fission - asexual

label the diagram

a - sepal

b - petal

c - stamen

d - carpel

e - anther

f - filament

g - stigma

h - style

i - ovary

j - ovule

write 3 points about asexual reproduction

• only 1 parent cell is required and it divides via mitosis

• offspring will be genetically identical

• has a higher survival value in a stable environment

write 3 points about sexual reproduction

• 2 parents are needed as you need 2 gametes (F + M), each passes down half their genetic info in their haploids which are formed by meiosis

• offspring have genetic variation

• have a higher survival value in a changing environment

what are runners and an e.g.

natural method - asexual

in a plant part of the parent plant forms a new plant, e.g. runners, that spread over the ground and sprout roots at intervals

e.g. strawberries

what are cuttings

an artificial method of runners

what is pollination

the transfer of pollen from the anther of one flower to the stigma of another, to allow for fertilisation

what is fertilisation

the fusion of the nuclei of the male and female gamete that occurs in the ovule after a pollen tube forms

what is seed dispersal

dispersing of seeds far away from parent plant to limit competition

how is the stigma adapted for wind pollination

it is found outside the flower and is feathery and flexible to catch drifitng pollen in the wind

how is the filament adapted for wind pollination

it hangs outside the flower and is loose and long

how is the anther adapted for wind pollination

hangs on the outside and produces lots of lightweight pollen

how is the stigma adapted for insect pollination

it is found inside the flower and is sticky so pollen grains attach to it

how is pollen adapted for insect pollination

it is large and sticky/ spiky to attach to insects to be carried away

give 3 differences between wind and insect pollinated flowers

insect pollinated flowers are large and brightly coloured to attract insects while wind are small and dull

insect pollinated flowers produce nectar while wind dont (NOT FOR STRUCTURE)

insect pollinated produce sticky pollen while wind produces lots of lightweight pollen (NOT FOR STRUCTURE)

Insect pollinated flowers have their stigma enclosed while wind dont

insect pollinated flowers have their anther enclosed while dont

how are gametes made

meiosis

how is a zygote developed into an embryo

mitosis

when the flower develops into fruit what does the ovule become

seed

when the flower develops into fruit what does the ovule wall become

seed coat

when the flower develops into fruit what does the zygote (fertilised ovum) become

embryonic plant ( with a radical and plumule)

when the flower develops into fruit what does the ovary become

the fruit

when the flower develops into fruit what does the rest of the ovule become

the food store

when the flower develops into fruit what does the ovary wall become

fruit coat

what are the methods of seed dispersal

wind

animal, internal/ external

water

self-propelled, explosion

what is the embryo

the young shoot and root (plumule and radical) that will become the adult plant

what is the food store in the seed

also called cotyledon

contains starch for the germinating plant, until it can photosynthesise

what is the seed coat in a seed

a tough protective outer covering

what acronym should you use for germination

WOW

water

oxygen

warmth

how will a dormant v germinating seed test for starch

both will test positive, although a germinating seed will only have small amounts

how will a dormant v germinating seed test for reducing sugars

a dormant seed will test negative, only contains starch

a germinating seed will test positive as the starch has been broken down

describe the events that lead to seed formation

• first pollination occurs on the stigma of the flower

• a pollen tube then forms down the style into the ovary

• the pollen nucleus passes through the tube into the ovule

• the nucleus of the male and female gamete then fuse

• the ovule then become the seed

• the ovule wall becomes the seed coat

• the ovary becomes the fruit

how can you see if germination has occured

shoot and root are visible

why is it important for seeds to have a food store

• seeds don’t have leaves and are usually found underground

• therefore they can’t photosynthesise to release energy

• this food store gives them the energy they require for respiration

advantages of seeds germinating away from the parent plant

• there is less competition for water, minerals and light

advantage of seeds germinating close to the parent plant

there is a guarantee that the environment is stable and suitable

explain the conditions needed for seed germination

water - softens the seed coat and allows enzymes to breakdown the food store as they require solution

oxygen - required for respiration

warmth - allows enzymes to reach their optimum temp.

why are some fruits surrounded by brightly coloured sweet tasting fruit

to attract animals

to consume fruit

as they contain glucose

for seed dispersal

why could seeds of edible plants and fruit be found at sewers and drains

after human ingestion and egestion they travel through pipes to the drains/ sewers