NCERT 6th Class (CBSE) Science: Getting to Know Plants

Question: Differentiate between tap roots and fibrous roots?

Answer: Tap Roots:

1. It has 1 main primary root which arises from the base of the stem other roots are called secondary root.
2. It can go very deep.
3. It is stronger than (monocot) fibrous root.
4. It is founded in dicot plants.

Fibrous roots:

1. Many small like roots that arise from the base of the stem.
2. It cannot go that deep.
3. It is not that stronger like tap roots.
4. It is found in monocot plants.

Question: Briefly explain various roots modifications.

Answer:

1. Sliet Roots: to give extra supper to thin and long stem so that it can storm erect. Eg- lamboo, sugarcane.
2. Prop roots: roots that reach the ground and fix themselves in the soil and give support to spreading branches.
3. Roots for support: money plant to help in attaching the weak stem to support.
4. Breathing roots: man grooves help the roots to breath in marshy are.
5. Staring roots: carrot, Radish, turnip, store food for the plant.

Question: Briefly explain various stem modification.

Answer:

1. Storing food: Some plants like potato, onion, garlic and sugarcane Store food in their stems.
2. Photosynthesis: Cactus, young plants have chlorophyll which makes photosynthesis.
3. Support: Tendrils, grape vine take support from any thing that they find nearby.
4. Protection: Rose protects itself through its thorns present on its stems.
5. Storing water: Cactus, baobab store water in their stems.

Question: Draw a well labelled diagram of a leaf with it functions.

Answer: Functions:

1. It exchanges gases through stomata.
2. Makes food by photosynthesis.
3. Photosynthesis
4. Respiration
5. Transpiration (loss of water)

It is also known as food factory of the plant.

Question: What are the functions of the network of wins in a leaf?

Answer: The veins in a leaf transport water, minerals and food and they also provide support to the leaf.

Question: What is pollination?

Answer: Pollination occurs when pollen grains ferried from the an these to the stigma. After pollination, the ovary swells up to become a fruit and the ovules change into seeds.