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• Plants are classified into trees, herbs, shrubs, climbers and creepers
• Trees –
  • Very tall, has thick and strong stem further divided into branches
  • Stem / trunk is big brown woody
  • Requires large space for spreading and lives for longer life
  • E.g. Coconut tree, Neem Tree, Ashoka Trees, Mango tree, Pine tree, Banyan Tree, etc.
• Shrubs –
  • Are short, have hard and thin stem
  • Have many thin brown woody stems
  • Require small space and live for shorter time
  • E.g. Rose plant, cotton plant, hibiscus plant, etc.
• Herbs –
  • Are shorter than shrubs, have weak, thin green stem
  • Stem is that much strong just to allow plant to stand straight on ground and doesnot have branches
  • Require very small space and live for short time
  • E.g. Aloevera, Tulsi, wheat, coriander, spinach, paddy etc.
• Climbers –
  • Have soft, weak, green stems
  • They stand upright, instead of spreading on the ground they take support of objects and climb vertically
  • E.g. bitter gourd, pea plant, bean plant, bottle gourd, bougainvillea etc
• Creepers –
  • Have soft, weak green stems
  • Cannot stand upright, thus are spreaded on the ground
  • E.g. Pumpkin, Watermelon, muskmelon etc.
• Stem
  • Stem – a part of plant that supports branches, leaves, flowers and fruits.
  • Nature of stem – Some plants may have thick stem like banyan, mango, etc, whereas some may have thin stem like Aloevera, Tulsi, coriander, spinach, etc. Some stems can be tender like all creepers
  • Location of stem – Stem can be below the ground like ginger, potatoes, sweet potato, or can be above the ground like neem, banyan, tulsi, coriander
  • Use – Some stems can be used as food like sugarcane, potato, sweet potato.
  • Functions – Stem is responsible for transport of water and food in the plant body.
• Leaf
  • Leaf – flat, green structures on the stem or branches
  • Shape size and structure of leaf – Leaves are found in various shapes sizes and color. Lamina is the flat green surface of the leaf. Boundary of leaf is called leaf margin. Stipules are the tiny leafy structure present near the leaf. Petiole is tubelike structure attach to a leaf. The prominent vein in the leaf is midrib.
  • Venation – arrangement of veins in the leaf blade.
  • Types of venation – Parallel venation and reticulate venation
  • Functions of leaf – carryout photosynthesis and transpiration in the plant body
  • Uses – Used as food material in the form of leafy vegetables, can be used as medicines, etc
• Root
  • Root – part of plant which is present in the soil
  • Functions – Holds soil tightly and allows plant to stand straight or erect on the ground
  • Origination of roots – during the germination of seed radicle so formed develops into roots
  • Types of roots –
    

    Tap roots	Fibrous roots	Adventitious roots
    Single large main roots The lateral roots originates from taproot Found in caster, pea, mango, turnip, carrot, beans, etc Found in dicot plants Has reticulate venation in leaf	Large number of similar roots spread in the soil Appears like fibres Found in grasses, wheat, rice, banana, maize Found in monocot plants Has parallel venation in leaf	Roots that grow from any other part of plant above the soil Support and provide nourishment to plant Plant can survive even after the death of main stem Found in banyan tree

• Flower –
  • Flower – Plant part which blossoms
  • Function – Reproduction
  • Parts of flower –
  • Pedicel: Flower is attached to stem or branch with the help of long stack like structure called as pedicel
  • Receptacle: Flower is supported by a swollen part called as receptacle.
  • Calyx: When the flower is in bud, it is protected by a green, whorl, called calyx. When the flower is in bloom the whorl develops into green leaf-like structures called sepals. Together, sepals are called calyx.
  • Corolla – Bright coloured parts having pleasant smell, found in different shape, size
  • Androecium: It is the male reproductive part of the flower which consists of stamens. Each stamen is made of anther and a stalk or filament. Anther produce pollen grains, which are the male reproductive cells in plants.
  • Gynoecium: It is the female reproductive part of the flower, which consists of carpels. Each carpel is made of stigma, style and ovary. Stigma is Sticky Terminal Part where Pollen Grains germinate. Style is Middle Elongated Part on top of which stigma is located. A tube called pollen tube is formed in style which transfer pollen grain from stigma to swollen bottom part of flower called ovary. Ovary contain ovule which are female reproductive cells.
  • Unisexual flowers – Flowers having either male or female reproductive system. E.g. papaya
  • Bisexual flowers – Flowers have both male or female reproductive system. E.g. rose, tomato, etc

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