Category: VBQs For Class 12

Very Short Answer Type Questions Question.  Why does ‘Swiss cheese’ have big holes?– Thinking ProcessDifferent varieties of bakery like bread and cheese are known by their characteristic texture, flavour and taste, the specificity coming from the microbes used.Answer. The large holes in ‘Swiss cheese’ are due to production of a large amount of CO2 by a bacterium named Propionibacterium […]

MULTIPLE CHOICE TYPE QUESTIONS Question. The discovery that led to the development of first antibiotic was made by(a) Jenner(b) Pasteur(c) Fleming(d) Waksman Question. Genetically engineered bacteria have been used in commercial production of(a) Thyroxine(b) Testosterone(c) Human insulin(d) Melatonin Question. Hepatitis B vaccine is(a) First generation vaccine(b) Second generation vaccine(c) Third generation vaccine(d) Interferon Question. Antigens are present(a) […]

SHORT ANSWER TYPE QUESTIONS  Question. Why is Agrobacterium mediated genetic transformation describe as natural genetic engineering in plants?Answer.(i) Agrobacterium tumefaciens pathogen of dicot plants is able to deliver a piece of DNA known as T-DNA to transform normal plant cell into tumour.(ii) Ti plasmid of Agrobacterium tumefaciens has been modified into a cloning vector, which […]

Short Answer Type Questions Question. Name the two type of nutrient cycles existing in nature. Where are their reservoirs present ? State the functions of the reservoirs.Answer : The nutrients are never lost from an ecosystem but are recycled time to time and again indefinitely.Nutrient cycles are of two types :(i) Gaseous cycles : The […]

MULTIPLE CHOICE TYPE QUESTIONS Question. The substance produced by a cell in viral infection that can protect the other cells from further infection is:(a) Serotonin(b) Colostru(c) Interferon(d) Histamine Question. The antibodies present in colostrum which protect the new born from certain diseases is of:(a) IgG type(b) IgA type(c) IgD type(d) IgE type. Question. Which form […]

Very Short Answer Type Questions Question. Why are analogous structures, a result of convergent evolution ?Answer : Analogous structures are a result of convergent evolution because they are not anatomically similar structures though they perform similar functions. Detailed Answer :Analogous structures are said to be the result of convergent evolution because, though they perform a similar function […]

Very Short Answer Type Questions Question. Mention the contribution of genetic maps in human genome project. Answer : Sequencing of genes, DNA finger printing, tracing human history, chromosomal location for disease associated sequences. Question. Mention the role of the codons AUG and UGA during protein synthesis.Answer : AUG – codes for methionine / initiation codon.UGA – termination codon / stop codon.  Short […]

Short Answer Type Questions Question. Explain the laws that Mendel derived from his monohybrid crosses.Answer : Law of Dominance, states that factors that control characters occur in pairs and in dissimilar pair one factor dominates (expresses itself) whereas the other recessive factor does not express in the presence of the dominant one.Law of Segregation, states that during […]

Very Short Answer Type Questions Question. Name the pouch in which the human testes are present. Answer : Scrotum. Question. Name the cells that nourish the germ cells in the testes. Where are these located in the testes ?Answer : Name of cells—Sertoli cells.Location—They are found lining-up the inner surface of seminiferous tubules.  Question. Write the […]

Very Short Answer Type Questions Question. Explain the process of pollination in Vallisneria.Answer : The female flower reaches the surface of water by long stalk, male flower releases the pollen grains on surface of water, pollen grains are carried by water currents, some of them reach the stigma and achieve pollination.  Question. What is pollen–pistil interaction and how […]