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This is a presentation about the classification of plants
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•We will learn that plants produce flowers which have male and female organs.
•We will learn that seeds are formed when pollen from the male organ fertilises the female organ.•And finally, we will learn how plants get nutrients and how they reproduce
•We will learn the plant classification•We will learn to label the parts of a plant and flower.
There are more than 250.000 plant species on Earth. They can be classified into two groups: non- flowering plants and flowering plants
Non flowering plants are the smallest group. They never produce flowers or seeds. They reproduce with spores.
1.Mosses: are very short plants with tiny stems, leaf and root structures. They live on rocks, on tree trunks and on the ground.
2.Ferns are much longer than mosses. They have thick, underground stems and large leaves.
Non- flowering plants grow in dark, humid forests.
Ferns Mosses
Flowering plants are the most numerous. They produce flowers and seeds to reproduce. They can be classifies into two groups:
1. Gymnosperms: have small, simple flowers. They don’t produce fruit. The seeds are grouped together in cones.
Most gymnosperms are trees which have leaves all year. As a result, they are called evergreen. Cypress trees, pines are gymnosperms.
2. Angiosperms have large, beautiful flowers. They produce seeds and fruit
This is the largest plant group. It includes trees, bushes and grasses. Chestnuts trees are angiosperms. Angiosperms which lose all their leaves in autumn are called deciduous plants.
GYMNOSPERMS
ANGIOSPERMS
1. R
2. S
3. L
4. F
oots
tem
eaves
lower
Look at this picture.
Can you label the parts of the plant?
The roots absorb water from the soil.
The stem helps to
support the plant.
The leaves use sunlight
to provide the plant with energy.
The flower helps the plant to
reproduce.
What does it smell like?
What can you see?
This is the name for the FEMALE part of the flower.
This is the name for the MALE part of the flower.
(female part)
(male part)
stigma
style
ovary
anther
filament
pollen
Plants are autotrophs: they make their own food. Plants need sunlight, air, water and minerals to make food. To use this food, plats breath all the time, day and night.
How do nutrients enter plants?
Plants absorb the water from the soil through their roots and tiny root hairs. These nutrients, called raw sap, then travel up the stem to the leaves through long tubes called xylem vessels.
Photosynthesis is the process which enables plants to manufacture food from water, carbon dioxide and sunlight. It takes place in the leaves and other green plant cells.
Chlorophyll is the green substance in the leaves which traps sunlight.
Plants give off oxygen
How does pollination take place?
• Pollen grains brush against the insect, it flies to another plant, the grains rub on the stigma
• The grain of pollen grows a tube, which goes down the style until it reaches the ovary
• The male part joins with the female part to form a seed. This is called fertilisation.
• After fertilisation the petal drop off because they are no longer needed
• Sometimes the wind blows pollen from small, less attractive flowers.
When the pollen grains reach the ovary, the flower begins to change into a fruit. Then the petals fall off. The ovary grows much larger, and finally turns into a fruit with seeds inside
Seeds need special conditions to germinate. Germination requires moist soil and relatively warm temperatures
Many plants can reproduce without flowers or seeds. This is called asexual reproduction
Asexual reproduction uses tubers, bulbs or stolons
1. Tubers: are subterranean stems. A part of the stem grows above ground and other part grows underground. Potatoes are tubers
2. Bulbs are also subterranean stems. Onions are bulbs.
3. Stolons: they extend above ground. When a stolon touches the ground , it develops roots. Soon a new plant develops. Strawberry plant reproduce this way