Digestion and Absorption — BIOLOGY STD 11 Science — Question

Describe the male reproductive system of frog by drawing a labelled diagram.

How do you prepare your own herbarium sheets? What are the different tools you carry with you while collecting plants for the preparation of a herbarium? What information should a preserved plant material on the herbarium sheet provide for taxonomical studies?

Draw the floral diagram of Liliaceae and write its floral formula. Write two major differences between the flowers of this family and those of Solanaceae.

How do neutral solutes move across the plasma membrane? Can the polar molecules also move across it in the same way? If not, then how are these transported across the membrane?

Manish while performing a practical in laboratory on Grams stain observed that one type of bacteria stained dark blue or purple in colour, while the other type of bacteria did not retain the crystal violet dye even after staining again and again. Instead it keeps on loosing the dye on washing. He rushed to his teacher for showing the specimen.His teacher explained that there is nothing to get worried about. As different kinds ofbacteria are found.

1. What is the basis of classifying bacteria.
2. What is the basic difference between Gram positive and Gram negative bacteria.
3. Name one Gram positive and one Gram negative bacteria.
4. What values are shown by Manish's teacher?

Illustrate the differences between the mechanism of action of a protein and a steroid hormone.

Explain the difference between the following and make a labelled diagram of the parts of a flowering plant.
1. Difference between stipule and bract
2. Phyllotaxy and Venation

What conditions enable RuBisCO to function as an oxygenase? Explain the ensuing process.

Write short notes on the following: (i) Symmetry, (ii) Coelom, (iii) Segmentation, (iv) Bicore and tricore organization.

Describe stem. Explain various modifications of stem.