Cell The Unit of Life — BIOLOGY STD 11 Science — Question

What are trimerous flowers? Which group of plants has trimerous flowers?

1. Name the pigment found in the root nodules of legumes.
2. How does this pigment protect the enzyme nitrogenase?

OR
Which substance imparts pink colour to the root nodules of leguminous plants? State its function.

State the law proposed by Blackman for various factors operative for photosynthesis.

Identify the lipid molecule that is crystallisable in nature. Also, give the name of the disorder produced by it in the human body.

What is the importance of vacuoles in Amoeba?

Why cannot reproduction be consolidated as a defining characteristic of living organisms?

Fluke infections are diseases of the _______ in humans.

1. Blood.
2. Bile.
3. Digestive tract.
4. Lungs.

Draw a well-labelled diagram of sclerenchyma.

Given below are the pairs of cell organelles and their functions. Which out of these is not a matching pair and why?

1. Mitochondria: Produce cellular energy in the form of ATP.
2. Golgi apparatus: Site of formation of glycoproteins and gloycolipids.
3. Smooth endoplasmic reticulum: The major site for synthesis of lipid.
4. Centrosome: Trap light energy for photosynthesis.

A character found exclusively in mammals, is:

1. Internal fertilisation.
2. Muscular diaphragm.
3. Four-chambered heart.
4. Homoeothermy.