Biology 2014-2015 HSC Science (General) 12th Standard Board Exam Question Paper Solution

A cross used to verify the unknown genotype of the F₁ hybrid is a ______.

Test cross

Back cross

Dihybrid cross

Monohybrid cross

Appearance of new combinations in F2 generation in a dihybrid cross proves the law of_____________ .

1. dominance
2. segregation
3. independent assortment
4. purity of gametes

A fine powder of recycled modified plastic is known as ______.

polyblend

polythene

polyester

polymer

The partially decomposed organic matter is formed by a process called ______.

fragmentation

humification

mineralisation

leaching

Transfer of genetic material into a bacterial cell through a viral vector is known as ______.

transformation

transduction

transfection  

translation

If the number of chromosomes in an endosperm cell is 27, what will be the chromosome number in the definitive nucleus?

1. 9
2. 18
3. 27
4. 36

Lever mechanism of pollination is observed in

1. Salvia
2. Jasmine
3. Bougainvillea
4. Butea

A pea plant pure for yellow seed colour is crossed with a pea plant pure for green seed colour. In the F₁ generation all pea plants were with yellow seeds. Which law of Mendel is applicable?

Name the enzyme responsible for the delay in the ripening of tomato fruit.

Which are the bacteria responsible for converting organic acids into methane?

Name the high-yielding semi-dwarf varieties of wheat selected and introduced in India in 1963.

'Formation of primary endosperm nucleus is called triple fusion'. Give reason

Mention any 'two' ecological services forthe benefit of mankind

Sketch and label 'tubular tower fermenter'.

Global warming is caused by the 'greenhouse effect'. Justify.

With the help of a neat and labelled diagram explain VAM (vesicular arbuscular mycorrhizae).

Distinguish between light and dark reactions.

Mendel selected the garden pea plants for his experiments. Explain

With the help of a neat and labelled diagram describe the steps in recombinant DNA technology.

What is 'tissue culture'?

Describe the methodology of tissue culture.

Define vegetative propagation.

Differentiate between 'stem tuber' and 'tuberous root'.

Sketch and label T.S of angiospermic anther.

With the help of a neat and labelled diagram describe Watson and Crick's model of DNA.

With the help ofschematic representation explain Krebs cycle.

In gene therapy, DNAase is used to treat _______________.

Cystic fibrosis

Haemophilia

Pituitary dwarfism

Insulin-dependent diabetes

If only one 'X' chromosome is found in a female person, which of the following symptoms she will show?

1. epicanthal skin fold
2. webbing of neck
3. small testis and absence of spermatogenesis
4. presence of simian crease on the palm

In which of the following haploid cells a whole genome in human being is present?

1. sperm
2. somatic cell
3. mature RBC
4. primary spermatocyte

Which of the following is NOT an example of connecting link?

1. Archaeopteryx
2. fchthyostegia
3. Seymouria
4. Biston betularia

In____________ , superior males of one breed are mated with superior females of another breed.

1. out crossing
2. cross breeding
3. out breeding
4. inbreeding

Normal activities of the heart are regulated by ______________.

brain

brain

spinal cord

spinal cord

modified cardiac muscles

modified cardiac muscles

During .............. typs of interaction, both organisms are benefited

1. mutualism
2. competition
3. commensalism
4. parasitism

What is gene pool?

Give any 'two' names of X-linked diseases

What does abbreviation HGP stand for?

Give 'two' varieties of silk which are considered  as inferior quality

In the electrocardiogram shown below, which wave represents ventricular diastole?

Which method of conservation of biodiversity includes 'hotspot' method?

Sketch and label the ventral view of the human heart.

Distinguish between ape and man.

Give the applications of DNA fingerprinting technique.

Explain the various types of cancer

Give the significance of fertilization.

What will be the phenotype of progeny, if a carrier haemophilic female marries a normal male?

Explain with tile help of a chart, explain the compatibility of human blood groups.

Justify the conservation of endangered species of plants and animals is necessary

Justify Pollution Under Control (PlUC) certificate is mandatory for all vehicles and industries

Sketch and label 'structure of nephron'.

With the help of a labelled diagram of lateral view of cerebrum, describe the structure .

Give any two functions of the cerebrum.

With the help of a neat, labelled diagram describe the human male reproductive system.