Slide1: PLANTS –What you need to know. Slide2: To succeed in the SAT’s you must know the following about plants:
The three main parts of a plant
Flowers and fertilisation
Conditions for plants to grow
Lifecycle of a plant
Slide3: Plants and trees have three main parts: 1. Head/Leaves 2. Trunk (trees) or stem (flowers) 3. Roots Slide4: Starting at the bottom: ROOTS This is the part of the plant that anchors (fixes) it into the ground so that it doesn't fall over.
The roots also absorb water and minerals from the soil. Slide5: Roots grow underground and seek out water and nutrients. The water and nutrients are then transported up through the roots.
1. Support for the leaves, flowers and fruits.
-Without the stem / trunk the plant would not stand up against the wind and all of the leaves, flowers and fruits would be stuck on the ground. The Stem / Trunk Stems have four main functions which are:
Slide7: This is the part of the plant that links the roots to the leaves and flowers.
The Stem / Trunk 2. The stem carries water and minerals from the roots to these parts. Slide8: The Stem / Trunk 3. The stem allows access to sunlight
The stem / trunk pushes the leaves, fruits and flowers towards the sunlight ready for photosynthesis Slide9: 4. The stem stores water and nutrients for the plant to use later.
-This is to you storing food in your stomach. The Stem / Trunk Slide10: The head of the plant is often either: Leaves Flowers or …or both! Slide11: The Leaf Catching and storing rain water
Photosynthesis (Click here for an explanation) Back to leaves and flowers Slide12: Photosynthesis is when plants create oxygen so that we can breathe!
It’s like a big recipe.
Sunlight (caught by the leaves),
Water (caught by the roots and leaves)
Carbon Dioxide (a gas in the air caught by the leaves)
The plant takes these “ingredients” and makes:
Oxygen (So that we can breathe!) and
Glucose (A sugary food that the plant eats)
Just remember… CARBON DIOXIDE + + = (Sunlight) (Water) (Gas) Slide14: OXYGEN This allows us all to breathe. Can you see why plants are important now? GLUCOSE This is a sugary food that the plant eats. It is the only living organism on this planet that makes food for itself. This is why it is at the beginning of every food chain! Photosynthesis creates: Back to leaves and flowers Back to contents page Slide15: Flowers Stamen Stigma Petal Back to contents page To pollination Slide16: The Stamen The MALE side of the flower that grows pollen. Boys only! Boys only!
Slide17: The Stamen is the male part of a flower. Each stamen generally has a stalk called the filament, and, on top of the filament, an anther.
The anther holds lots of pollen. Anther Filament Pollen pieces Go back to flower Slide18: The Stigma The FEMALE part of the flower where the pollen needs to get to! Girls only Girls only Girls only Girls only Slide19: Ovary Found in the middle of the flower the stigma is sticky and catches pollen and is connected to a tube called the style which leads downwards to the plants ovary. If pollen enters into the ovary a seed will start to grow. This is known as fertilisation. Style: If pollen passes through the style and to the ovary a seed will start to grow. Stigma Go back to flower Slide20: Flower Petals Petals do a similar job to leaves. They catch rain and sunlight. They are also bright sweetly scented and attract insects to them. Back to flower Continue Slide21: Seeds are dispersed (spread out) in four different ways:
Wind SEED DISPERSAL Why is seed dispersal important for plants? Seed dispersal happens when seeds are spread out over a wide area so that all of the new plants have enough room to grow. Back to contents page Slide22: Some seeds are dispersed by explosion. Peas have a seedpod that dries and splits, flinging the seeds over a wide area. Back to seed dispersal Slide23: Some seeds are dispersed by the wind. Grasses have fine, light seeds with 'whiskers' that are blown long distances by the wind.
Back to seed dispersal
Slide24: The seeds are dispersed by water. Coconuts have a thick outer coat and are designed to float in water
Back to seed dispersal
Slide25: The seeds are dispersed by animals. Seeds are dropped far away from the parent bush.
Holly has brightly coloured fruit to attract birds that eat them. Insects such as ants can carry seeds away from trees. Some seeds stick onto passing animals and later fall off. Back to seed dispersal
Slide26: What if the seeds were not spread out? As plants grow above the ground so do the roots in the soil. This is not good for two reasons:
There will not be much space for the trees and their roots will become tangled.
Each tree will be fighting for the water and nutrients in the soil. Most of the trees will not be able to find enough water and will starve. Back to seed dispersal
Slide27: Pollination is where pollen travels from the stamen to the stigma
Who helps flowers become pollinated? Slide28: Some plants are pollinated by insects. The large colourful petals and the nectar attract insects to the flowers. The plant's pollen then sticks to the insects and they carry it to the next plant they visit. Back to contents page Slide29: -How a seed “grows up” to become a plant. Seed Roots develop Stem develops Leaves grow towards sunlight Slide30: Germination A seed becoming a plant Back to contents page Slide31: The life cycle of a plant Back to contents page
Slide32: Plants don't grow well if they don't get the right raw materials.
If any of these raw materials are not included the plant will turn yellow and then wilt and die. Slide33: A plant is so clever it will grow to where ever sunlight is. Back to contents page