- Pedigree analysis helps determine the pattern of inheritance
of a trait among related individuals. One such pedigree is
given.
Squares indicate males and circles females. Filled symbols
indicate presence of trait while circles with a dot indicate
carriers. The inheritance pattern shown in the given pedigree is
(a) X-linked recessive (b) autosomal recessive
(c) sex limited trait (d) sex influenced trait.
(INBO 2017)
- Which one of the following plant traits is not associated
with colonisation on land from aquatic habitat?
(a) Presence of apical meristems
(b) Absence of alternation of generations
(c) Formation of multicellular, dependent embryos
(d) Production of gametes within multicellular organs
(INBO 2017)
- The nuclear membrane disappears during cell division.
After completion of cell division, it re-appears during the
interphase. Which of the following contributes towards
formation of the nuclear membrane?
(a) Spindle fibre proteins
(b) Cytoskeletal elements
(c) Endoplasmic reticulum
(d) Golgi bodies (INBO 2016)
- In C 4 plants, dimorphism of chloroplasts is an adaptation to
(a) absorb light efficiently
(b) absorb light in blue-violet and red regions
(c) carry out cyclic and non-cyclic electron transfer
(d) minimise photorespiration. (NSEB 2015-16)
- If the triplet base sequence for an amino acid in DNA is TTT,
what will be the anticodon for it?
(a) UUU (b) AAA
(c) TTT (d) CCC (NSEB 2015-16)
- Assuming that the number of chromosomes in the
endosperm of a gymnosperm is 80, the number of
chromosomes before and immediately after fertilisation in
each of the following structures will be
Structures Before
fertilisation
After
fertilisation
(a) Integument 80 160
Cells of archegonia 80 80
Nucellus 160 160
(b) Integument 80 80
Cells of archegonia 40 40
Nucellus 80 80
(c) Integument 80 80
Cells of archegonia 40 40
Nucellus 40 120
(d) Integument 160 160
Cells of archegonia 80 80
Nucellus 160 160
(INBO 2015)
- Poonam noticed a total of 64 setae in 4 bunches in each
segment of an annelid ‘X’ and 85 setae in a single ring in
certain segments of the body of an annelid ‘Y’. She should
classify ‘X’ and ‘Y’ as
(a) oligochaetes
(b) polychaetes
(c) oligochaete and polychaete respectively
(d) polychaete and oligochaete respectively. (INBO 2014)
- Cytokinins influence the movement of nutrients into leaves
from other parts of the plant. This phenomenon is known as
cytokinin-induced nutrient mobilisation. In an experiment
with cucumber seedlings, the left cotyledon of a seedling A
and right of seedling B were treated with 50 mM kinetin.
The [^14 C] amino iso-butyric acid (AIBA) was injected into
the right cotyledon of each of these seedlings.
AIBA injected
Seedling A Seedling B
AIBA injected
BIOLOGY
OLYMPIAD PROBLEMS
