Science (English Medium) Class 11 - CBSE Question Bank Solutions for Biology

What part of the plant would show the following:

Well developed pith

Formation of enzyme-substrate complex (ES) is the first step in catalysed reactions. Describe the other steps till the formation of product.

Which one of the following will not directly affect transpiration?

The process of guttation takes place ______.

Water moves up against gravity and even for a tree of 20m height, the tip receives water within two hours. The most important physiological phenomenon which is responsible for the upward movement of water is ______.

From your knowledge of physiology can you think of some method of increasing the life of cut plants in a vase?

Salt is applied to tennis lawns to kill weeds. How does salting tennis lawns help in killing of weeds without affecting the grass?

We know that plants are harmed by excess water. But plants survive under flooded condition. How are they able to manage excess water?

What is common to Nepenthes, Utricularia and Drosera with regard to mode of nutrition?

Sketch and label the ‘Ultrastructure of Chloroplast’.

The transverse section of a plant material shows the following anatomical features, (a) the vascular bundles are conjoint, scattered and surrounded by sclerenchymatous bundle sheaths (b) phloem parenchyma is absent. What will you identify it as?

While eating watermelons, all of us wish it was seedless. As a plant physiologist can you suggest any method by which this can be achieved.

Algae are known to reproduce asexually by variety of spores under different environmental conditions. Name these spores and the conditions under which they are produced.

What is the epidermal cell modification in plants which prevents water loss?

What are the cells that make the leaves curl in plants during water stress?

Point out the differences in the anatomy of, leaf of peepal (Ficus religiosa) and maize (Zea mays). Draw the diagrams and label the differences.

Palm is a monocotyledonous plant, yet it increases in girth. Why and how?

Reaction given below is catalysed by oxidoreductase between two substrates A and A’, complete the reaction.

A reduced + A’ oxidised `→`

The C₄ plants are twice as efficient as C₃ plants in terms of fixing CO₂ but lose only ______ as much water as C₃ plants for the same amount of CO₂ fixed.

In a girdled plant, when water is supplied to the leaves above the girdle, leaves may remain green for sometime then wilt and ultimately die. What does it indicate?