SECTION - C
- (i) Draw a neat and labelled diagram of a fertilized
embryo sac.
(ii) Describe briefly the type of fertilization found only in
angiosperms.
- refer to the given figure and answer the following
questions.
(i) What does the given figure show?
(ii) Which of the labelled structures is a pre-birth structure
and is not formed thereafter?
(iii) Which of the labelled structures responds to LH surge by
rupturing?
- Study the given pedigree chart and answer the questions
that follow.
(i) Is the trait recessive or dominant?
(ii) Is the trait sex-linked or autosomal?
(iii) Give the genotypes of the parents in generation I and of
their second and third child in generation II.
- Study the mrNa segment given below which is to be
translated into a polypeptide chain.
(i) Identify the codons represented by ‘a’ and ‘b’.
(ii) What do they code for?
(iii) How is a peptide bond formed between the amino acids
on the ribosome?
- (i) How can the Hardy–Weinberg’s expression
be used to identify if a population is evolving?
(ii) List any two factors that can disturb the genetic
equilibrium.
OR
The population of light coloured peppered moth Biston
betularia was almost replaced by the black variety
during the industrial revolution in england. explain the
mechanism involved.- (i) Name the property that enables the explants to
regenerate into a new plant.
(ii) a banana herb is virus-infected. Describe the method
that will help in obtaining healthy banana plants from
this diseased plant. - (i) How is activated sludge produced during sewage
treatment?
(ii) ex p l a i n h o w t h i s s l u d g e i s u s e d i n b i o g a s
production. - The given diagram is of an E.coli cloning vector.
(i) Identify the selectable markers among (a) - (d) in it.
(ii) How is the coding sequence of b-galactosidase
considered a better marker than the ones identified
by you in the diagram? explain, giving reason.- What are bioreactors? List five growth conditions
that a bioreactor provides for obtaining the desired
product. - ‘Plasmids are a boon to biotechnology’. Justify this
statement quoting the production of human insulin
as an example. - The given figure shows the different types of age
pyramids for human population.
(i) What does the parts ‘X’, ‘y’ and ‘Z’ represent?
(ii) Which type of population is represented in pyramids
a, b and C?