Categorieën: Alle - cytoplasm - chloroplast - pollination - nucleus

door Angela zhang 6 jaren geleden

221

Reproduction in plants

Plants have intricate systems and structures essential for their growth, reproduction, and survival. The cytoplasm is a jelly-like substance where cell activities occur, and the nucleus, found within the cytoplasm, controls these activities and contains genetic information.

Reproduction in plants

Pollinators visit flower because it either attracted to the flower petals or for food(nectar)

systems

only adult plant can reproduce!

adult plant

young plant

seed

flowering plant

dispersal

splitting/explosive action
Rubber fruits
saga pod
Some fruits split open when they are ripe to shoot their seeds out in different directions. Other fruits split open to release their seeds only after the fruits have dried up.
animal dispersal
berry fruits
grasses bristles
Seeds found in fleshy fruits are dispersed when animals eat the fruits and throw away the seeds.Some animal eat both the fruit and the seed and pass the seeds out in their droppings.Some seeds have sticky hairs.They get dispersed by sticking to the fur of animals or humans.
wind dispersal
dandelion
shorea
Fruits or seeds dispersed by wind are usually light and small.They are easily carried by the wind.Some fruits and seeds have wing like structure that help them say longer in the air.This allow the fruits and seeds to be carried over greater distances.
water dispersal
nipah
coconut
Plants that grow in or near water disperse their fruits or seeds by releasing them into the water.These fruits usually have fibrous husks which trap air,or waterproof coverings.These help the fruits to stay afloat in water.The fruits are then carried along streams and rivers,or out to sea to distant location.
to prevent competition of space,water,nutrients,sunlight with parent plants or other plant
plant are likely to have a thicker stem when they do not grow in a overcrowed place.
overcrowding can cause plants to grow tall and thin.

fertilisation

1.When pollen grains land on the surface of the stigma, each pollen grain produces a pollen tube. 2.This tube grows down from the stigma,through the style to the ovary.The ovule is found in the ovary of the flower.Inside each ovule is an egg cell. 3.When the pollen tube reaches the ovule,the male reproductive cell in the pollen tube fuses with the egg cell.(Fusion of the male reproductive cell with the egg cell is called fertilisation)
The flower petals

The ovary starts to swell to form a fruit.The ovules start to develop into seeds.

Seeds continued to develop inside the fruit and the fruit grows bigger.

Flower petals wither

Ovary starts to swell to form fruit. The ovules starts to develop into a seed.

The seed continues to develop inside the fruit and the fruit grows bigger.

Female

ovule
-contain egg cells
ovary
-contains ovules -protects ovules
style
-connects stigma to ovary
stigma
-allow the pollen grains to stick on to it

pollination

pollen grain transferred to to stigma.
cross-pollination
self-pollination
by pollinators

-large -brightly coloured -scented to attract insects -anthers do not hang out of the flowers -stigma is sticky to catch pollen grains -has sweet nectar -stamens and stigma are hidden inside flowers. -Pollen grains are larger and heavier with a rough surface for sticking to an insect’s body. -A smaller number of pollen grains is produced.

balsam

wild orchid

rose

buttercup

bees

by wind

-usually small and dull coloured and no scent -anthers hang out of flowers so that pollen grain are easily shaken free and carried by wind -stigma is large and feathery in order to catch pollen grains floating in the air.it is not sticky -Pollen grains are smaller, smoother, lighter and easily blown by the wind. A larger number of pollen grains is produced.

oak

pine

maize

grass

Male

filament
-supports the anther
anther
-contains pollen grain

-contain male reproductive cells.

pink--function

Petal does not belong to either female or male.

orange--female parts of flower

red--male parts of flower

Reproduction in plants

reproduce to ensure the continuity of its kind

germination

condition needed to germinate
air(oxygen)
water
warmth(a suitable temperature)
The root of the baby plant grows first.During this stage,the baby plant is not unable to make its own food.It gets its nutrients from the food stored in its seed leaves
The shoot grows next

The young plant start making its own food when it develops leaves.

non flowering plants

fern
reproduce by spores
found in the spores bag under the leaf of nonflowering plant

plants

plant cell
cell wall

found outside the cell membrane.it supports and give the plant cell its shape

cyctoplasm

a jelly substance where cell activities takes place.

cell membrane

a thin membrane that surrounds the cytoplasm.It controls the movement of substances in and out of the cell.

nucleus

controls all activities in a cell found in the cytoplasm, it contains information that is passed down from parents to young.

chloroplast

structures that contain chlorophyll, the green pigment that traps sunlight to make food for the plant.

fruits(adult flowering plant only)
protect the seed/s
flower(adult flowering plant only)
to produce the fruit that contains seeds
stem
transport food and water all around the plant

food carrying tubes

outer layer

water carrying tubes

inner layer

support the plant upright
leaves
make food for the plant
roots
hold the plant firmly to the ground
absorb water and nutrients from the ground