Body Fluids and Circulation — BIOLOGY STD 11 Science — Question

How does hierarchical system of classification help scientist to unravel the mystery of living world?

Both animals and plants grow. Why do we say that growth and differentiation in plants is open and not so in animals? Does this statement hold true for sponges also?

Each plant or group of plants has some phylogenetic significance in relation to evolution: Cycas, one of the few living members of gymnosperms is called as the ‘relic of past’. Can you establish a phylogenetic relationship of Cycas with any other group of plants that justifies the above statement?

i. What is meant by bioassay? Name the two bioassays that are used to examine auxin activity in plants.
ii. Name the hormone that acts as an antagonist to abscisic acid. From which microorganism was it extracted initially? List two bioassays of this growth hormone.

What are the structural characteristics of:

1. Meristematic cells near root tip?
2. The cells in the elongation zone of the root?

What is hemodialysis? Describe the various stages of its process.

Give atleast three points of differences between spring wood and autumn wood.

Differentiate between right ventricle and left ventricle.

In what kind of plants do you come across Kranz anatomy? To which conditions are those plants better adapted? How are these plants better adapted than the plants, which lack this anatomy?

(i) In aerobic respiration the respiratory coefficient is infinite. Please explain.
(ii) Define the following: (a) Floating respiration (b) Protoplasmic respiration (c) External respiration (d) Internal respiration.