Spectrum biology

(Axel Boer) #1

Section-A


1.These figures show the gynoecium of


(a)Papaver
(b)Michelia flowers.
Write the difference in the structure of their
ovaries.

2.A person who is allergic to pulses is advised to
take a capsule of Spirulina daily. Give the reason
for the advice.


3.The egg of an animal contains 10 chromosomes, of
which one is X-chromosome. How many autosomes
would there be in the karyotype of this animal?


4.Where is good ozone present? Why is it called so?


5.Name the two forms of reservoir of carbon, that
regulate carbon cycle in the ecosystem.


Section-B


6.Name the first human like hominid. Mention his
food habit and brain capacity.


7.How milk production is hormonally regulated.


8.What makes the nucleopolyhedrovirus a desirable


biological control agent?

9.Can an unfertilised, apomictic embryo sac give
rise to a diploid embryo? If yes, then how?
10.Differentiate between biopiracy and biowar.
or
Honey collection improves, when beehives are
kept in crop-field during flowering season.
Explain.

Section-C


11.What initiatives were taken for reducing vehicular
air pollution in Delhi? Has air quality improved in
Delhi?
or
‘Nature has a carrying capacity for a species.’
Explain the statement with suitable examples.
12.Two heterozygous parents are crossed. If the
two loci of genes in them are linked, what would
be the distribution of phenotypic features in
F 1 -generation for a dihybrid cross?
13.What is ecological succession? Where and why
would the rate of succession be faster in a newly
created pond or a forest destroyed by a forest fire?
14.Why are offsprings of oviparous animals at a
greater risk as compared to offspring of viviparous
animals?
15.‘Fertilization is not an obligatory event for fruit
formation in certain plants.’ Explain.
16.Most living organisms cannot survive at
temperature above 45 °C. How are some microbes
able to live in habitats with temperatures
exceeding 100 °C?
17.How does the antiparallel orientation of
DNA strands affects its replication?

A B
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