Most plants have three parts: roots, the stem and leaves.The ROOTS hold the plant in the ground. Roots absorb water and minerals that the plant needs to survive.The STEM supports the leaves of a plant, and distributes the water, minerals and the food the plant makes to the rest of the plant.There are two types of stems: -Herbaceous stems are soft and green. For example, grass and weeds.

-Woody stems are hard. For example, trees and shrubs (bushes) have a woody stem called trunk.

The LEAVES make food for the whole plant. Each leaf is composed of a thin sheet called a blade. The blade has veins. The leave is attachedto the stem by a petiole.The trees that lose their leaves completely in autumn are called deciduous, for example oaks.

The trees that keep their leaves all year round are called perennial or evergreen.

Plants can be classified into two main groups : 1) FLOWERING plants. These have organs like flowers, fruits and seeds that help them to reproduce. There are two types:

1-Angiosperms, like apple trees, are plants that grow fruit with seeds. The seeds are inside the fruit.

2-Gymnosperms, like pine trees, have seeds inside flowers (pine cones) but do not have fruit.

2) NON-FLOWERING plants. These have no seeds. They reproduce by spores. -Ferns have roots, leaves, stems and spores in the leaves.

-Mosses do not have roots, leaves or stems. Spores are produced in capsules.

ABSORB

RELEASE ABSORB

PLANTS make their own food through PHOTOSYNTHESIS:-During the DAY, leaves absorb carbon dioxide. Chlorophyll in the leaves collect solar energy. This solar energy transforms the carbon dioxide, water and minerals into glucose (sugar) and oxygen the plant needs to live.When plants produce more oxygen than they need, they release this excess oxygen through the leaves.

-At NIGHT, when photosynthesis stops (there is no solar energy), plants no longer release oxygen. During this time, plants don’t produce food. Only use nutrients to get energy to live. This activity releases carbon dioxide.

As a matter of curiosity…

Chlorophyll is in the chloroplasts in the plant cells. They are similar to solar panels. They capture solar energy and transforms it. Instead of electricity, chloroplasts produce glucose.

IMPORTANCE OF PHOTOSYNTHESIS

Photosynthesis is the most important process to life on Earth because:-It provides us with oxygen to breathe. For this reason plants are called the ‘lungs’ of the Earth.-It consumes carbon dioxide, which is toxic to most living things.-It transforms water and minerals into food. Then animals can feed on plants to get energy to live.

HOW DO PLANTS MAKE NUTRIENTS?1-Plants absorb water and dissolved minerals through the roots. This mixture of water and minerals is called RAW SAP.2-XYLEM VESSELS are tubes that carry the raw sap from the roots to the leaves.3-Leaves absorb carbon dioxide through pores called STOMATAS and photosynthesis takes place in the leaves.4-The nutrients formed in the photosynthesis are called ELABORATED SAP.5-PHLOEM VESSELS are small tubes that transport elaborated sap all over the plant.

SEXUAL Reproduction in Plants - FLOWERING Plants

It takes place inside the flower when two reproductive cells come together. This generates a new plant.Flowers are reproductive organs in most plants. There are 3 different TYPES of flowers:1-MALE: it produces pollen.2-FEMALE: it produces the ovules. 2

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3-HERMAPHRODITE: in many flowers, the male and the female parts are inside the same flower.

SEXUAL Reproduction in Plants. NON-FLOWERING PlantsNon-flowering plants don’t have flowers or seeds. So, they use spores to reproduce. FERNS, for example, reproduce this way:1-Spores in the leaves fall to the ground and transform into reproductive cells.2-After fertilisation (male and female cells together), a new fern begins to grow.

ASEXUAL Reproduction in Plants

Many plants that grow flowers and seeds can also reproduce through FRAGMENTATION.In fragmentation, a new plant grows from a fragment of the parent plant.Examples of fragments in asexual reproduction are:

CUTTINGS (geranium): stems produce new plants when separated form the parent plant.

STOLONS (strawberry): stems grow horizontally and develop roots.