Getting To Know Plants

· There are various types of plants in our surroundings - tall and short, big and small, while some are just green patches on the soil. 

· Plants are of different shapes and sizes, and have leaves of varying shapes and sizes. Some plants have flowers while others don't. 

· A stem, branch, roots, leaves, flowers and fruits are some of the parts of a plant. Out of these parts, flowers and fruits are the ones that may or may not be present in a plant.

Herbs, Shrubs and Trees:-

How are plants classified?

Characteristics of Plants:-

• Plants have many different characteristics. They are of different sizes, and might have tender (soft) or hard stems.
• The branches of some plants grow close to the ground and in other plants they grow higher up on the stem.
• Based on the above mentioned characteristics, plants are broadly classified as: Herbs, Shrubs and Trees.

Herbs:-

• Herbs are plants with green and tender (soft) stems. They are usually short and have very few branches. 
• Herbs can be defined as any of the seed bearing plants which do not have a woody stem and die down to the ground after their growing season.
• Many herbs are valued for their medicinal, savoury (spicy/salty) and aromatic properties.
• Basil, oregano, parsley and peppermint are some widely used herbs.

Oregano herb Oregano in bottle (used on Pizza)

Shrubs:-

• Shrubs are plants having branches at the base of their stem.  Most of them have a rounded shape formed from many small branches, growing either directly from the ground or from a hard stem. 
• Unlike herbs, shrubs have many woody stems above the ground. Their stems are hard but not very thick. 
• Flowering shrubs such as a rose shrub are commonly seen in gardens.

A Rose Shrub

Trees:-

• They are extremely tall plants that typically have a single stem (trunk). Their stems have branches in their upper parts, much above the ground.
• Trees give us so much, from shade to oxygen to fruits.

A Bamboo Tree A Coconut Tree

Creepers and Climbers

Creepers: 

• Creepers are weak plants that cannot stand upright (straight). 
• They spread horizontally on the ground, or grow around another plant or up a wall by extending their stems or branches. 
• Pumpkins and watermelons are creepers.

A House Covered With Creepers!

Climbers:

• Climbers are also weak plants that cannot stand erect without support. 
• They can only grow along the ground without support. However, if they get support, they can grow straight up. 
• Bougainvillea as well as Grapevine are examples of climbers.

Bougainvillea Is A Common Climber Plant.

Stem:-

• A stem is the stick-like, central part of a plant that grows above the ground. 
• It bears leaves, branches, buds, flowers and fruits.
• The stem helps in transporting water and minerals to other parts of the plant, as the water moves along the stem and into the parts attached to it, such as leaves.

Stem

Leaf: Parts and Functions

Leaf and Its Parts:-

• A leaf is that organ of a plant that performs the process of photosynthesis.

The Parts of A Leaf:-

• Petiole:  A petiole is the stalk that connects the leaf to the stem. 
• Lamina: The broad, green part of a leaf.
• Midrib: A midrib is the prominent (main/thick) line in the middle of a leaf.
• Veins: Veins are the thin lines branching from the midrib of a leaf.
• Leaf venation: The design, that is, the arrangement of veins on a leaf is called venation. 
• Parallel venation: If the veins run parallel to each other, it is called parallel venation. This is observed in grass. 
• Reticulate venation: If the venation on a leaf is net-like on both sides of the midrib, then it is called reticulate venation.

Reticulate Venation

Parts Of A Leaf

Transpiration:-

• Transpiration means the evaporation of water from plants. Just like humans need to sweat in order to keep themselves cool, plants need the process of transpiration. 
• This process is carried out by leaves. Water moves from the soil into the roots of the plant, then through the stem into the leaves. When this water is warmed by sunlight, it comes out of the stomata (tiny pores) on leaves.
• Transpiration depends on factors such as light, temperature, humidity and some others.

The Process of Transpiration

Photosynthesis:-

• Photosynthesis is the process carried out by leaves of a plant in the presence of sunlight in order to produce their own food. 
• This process needs sunlight, chlorophyll (the green substance present in plants), water and carbon dioxide. These substances are used during photosynthesis, whereas oxygen is given out. 
• The food thus prepared gets stored in different parts of the plant. It mostly consists of large quantities of sugars (glucose) as well as carbohydrates.

Process of Photosynthesis

Roots

Roots and Their Functions:-

• The stem provides the leaf with water, and the leaf uses it for producing food, and also loses some water through transpiration.
• Roots supply water to the stems.

The Major Functions of Roots:

(i) Roots anchor (hold) the plant in the soil.

(ii) They absorb water and minerals from the soil and conduct (lead, drive) them to leaves and other parts of the plant.

Types of Roots:-

• A taproot is the main root in a taproot system. It grows vertically downward. This can be seen in carrots.
• Lateral roots are those that develop from other roots. 

Lateral Roots

• Certain plants have a fibrous root system. Such a system does not consist of a single taproot. Instead, the roots grow downward and outward from the stem, branching repeatedly to form a mass of fine roots. These are fibrous roots.

Roots and Leaf Venation:-

• The type of roots and the leaf venation in a plant are connected. 
• In a plant that has a tap root has reticulated venation, and the leaves of plants with a fibrous root system have parallel venation.

Flowers

Parts of A Flower:-

Parts of Flower

Petals and sepals:

• Petals are the prominent parts of an open flower. They are the colored parts which are joined and together form the flower. 
• A bud is the small part on a plant that later develops into a flower.
• The most prominent part on a bud is made up of small leaf-like structures which are known as sepals.
• Some flowers have to be cut open if we wish to see their inner parts, as their petals are joined. 

Stamen and Pistil: 

• Stamen is the pollen-bearing part of a flower. 

• Pistil, on the other hand, is the innermost part of a flower. 

Ovary and ovules:

• Ovary of a flower is the lowermost and swollen part of the pistil, while ovules are the bead-like structures found inside the ovary.