STANDARD Botany Class 12 Questions

The dough kept overnight in warm weather becomes soft and spongy because of

Chargoff's rule states Or Which one of the following ratio is constant in DNAs of different species

Red data book provides data on

The linking of antibiotic resistance gene with the plasmid vector became possible with

These processes are necessary for the complete development of male gametophyte from pollen mother cell

Bacteria and fungi in a forest ecosystem are generally

The study of inter-relationship between living organisms and their environment is called

Who is considered as father of genetics

Biotechnology deals with techniques of

The food chain is a series of the population which starts with producers. It is concerned with

Ecology takes into account only

The organization which publishes the Red List of species is

______ and _____ were the proportion of plants that were dwarf & tall in F₂ generations of monohybrid cross.

One of the oldest food items in which microbes were used is _______

Exine of pollen grains is composed of

Purines of DNA are represented by

It is now possible to breed plants and animals with desired characters through

How many meiotic divisions are necessary to produce 100 pollen grains

_______ are used in detergent formulations and are helpful in removing oily stains from the laundry

The alleles are

A food chain starts with

Watson and Crick are known for their discovery that DNA

In a food web, each successive trophic level has

Mass of living matter at a trophic level in an area at any time is called

The outermost and innermost wall layers of microsporangium in an anther are respectively

Despite occupying about 70 per cent of the surface, the productivity of the oceans are only ________

Most resistant biological material is Or An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is

Pollen grains are generally spherical measuring about ______ micrometers in diameter

About 98 percent of the mass of every living organism is composed of just six elements including carbon, hydrogen, nitrogen, oxygen and

10% law of flow of energy in the ecosystem was proposed by

Energy enters into the ecosystem through

The function of innermost layer of pollen sac, tapetum is

The acid used for preliminary separation of biomolecule in a living tissue is

Which of the following is an artificial ecosystem

Match the following organisms with the products they produce A. Lactobacillus B. Saccharomyces C. Aspergillus niger D. Acetobacter aceti 1. Cheese 2. Curd 3. Citric Acid 4. Bread 5. Acetic Acid Select the correct option from the following

Amino acids are mostly synthesised from

Which of the following wall layers of anther play a predominant role in its dehiscence

Identify A, B, C and D in given figure

How many varieties of rice have been estimated to be present in India?

In a food chain, the total amount of living material is depicted by

The first link in any food chain is a green plant because

What does the filiform apparatus do at the entrance into ovule Or Function of filiform apparatus is to

Pollen-pistil interaction is a dynamic process involving ______ followed by ______.

_______ is used as an immunosuppressive agent in organ transplants, is produced by the fungus _______

Water hyacinth and water lily, the flowers emerge above the level of water and are pollinated by ______.

Sir Alexander Fleming extracted penicillin from

Embryo sac is

Which one of the most common embryo sac in flowering plant

A nucleotide is formed of

The rate at which light energy is converted into chemical energy of organic molecules is the ecosystem's