PART - 2 - Unit V : CH - 15 Body Fluids and Circulation — BIOLOGY STD 11 Science — Question

Draw a diagram of a flowering plant and write functions of different parts.

While teaching cell division in the class, teacher told that during meiosis, the chromosome number is reduced to half of the parent, whereas during mitosis, the number remains the same. Seema was not able to recognise what teacher explained in the class and asked her elder brother, a botany student, the need of reducing chromosomes during gamete formation and what will happen if chromosome number will not reduced to its half. He explained the concept in detail to Seema.

1. In which part of the organisms does meiosis occur?
2. How does meiosis help in evolution?
3. Give the significance of meiosis.
4. What value is expressed in the behaviour of Seema's elder brother?

How do you call the conduction of impulse along a myelinated nerve fibre?

Why nephridia in earthworm that is basically similar in structure is classified into three types? Mention the names of each.

How are the hypothalamic hormones transported to the target organs?

Enlist the demerits of an artificial system of classification of plants.

Describe the structure of adipose tissue briefly with the help of diagram.

Draw a well labelled diagram of the circulatory system of cockroach.

Explain the role of haemoglobin in transport of oxygen.

Ankita prepared hard for the test at home. All text based question and one practical based question on lock and key hypothesis was given to check whether the students had understood the phenomenon or not. Ankita who was a topper of class was the only student who was able to solve the problem. All others were unable to attempt the same. Teacher felt happy and asked Ankita to explain the process in the class.

1. Who proposed the lock and key hypothesis?
2. What is the nature of enzyme action?
3. Why are enzymes also called biocatalyst?
4. What values are reflected from Ankita's character?
5. The hypothesis was given by Emil Fischer in 1894.