(c) Anaphase I is the cytological event which
corresponds to Mendel’s law of independent
assortment.
(d) Compound corymb is also known as corymb.
Here the main axis (peduncle) branches in a
corymbose manner and each branch bears flowers
arranged in corymbs.
(c) Mitochondria is the common feature between
plant and animals.
(d) 5. (c)
(c) On Agarose gel electrophoresis, DNA
fragments can be separated and later can be
visualised after staining with a compound known
Ethidium bromide.
(c) According to tunica corpus theory, Tunica
is the outer consisting of meristems- peripheral
layers of cells, forming the outer region and
Corpus, the central undifferentiated multilayered
mass of cell.
(b) The center of flocs will become anoxic, which
would cause death of bacteria and eventually
breakage of flocs.
(d) Depending upon their colour, plastids are
of three main types-leucoplasts, chromoplasts
and chloroplasts. All plastids are derived
initially from small, undifferentiated plastids
termed proplastids, which are found in dividing
cells in meristems. During cell differentiation,
proplastids differentiate into particular plastid
types according to the type of cell in which they
reside.
(d) Aestivation is called as summer sleep, where
the organisms undergo physiologically dormant
state during summer.
(a)
(a) Plasmolysis is the shrinkage of protoplasm
when a cell is kept in hypertonic solution. It
can be reversed by placing the cell in hypotonic
solution.
(c) Utricularia, Drosera and Dionea are also
known as bladderwort, sundew and venus flytrap
respectively.
14. (d) Phytochrome is a soluble chromoprotein with
molecular mass 250 kDa. Plant grows towards
sunlight because the red light from sun converts
the chromoprotein into the active form (Pfr),
which triggers plant growth; plants in shade
show slow growth because the inactive form
(Pr) is produced. If seeds sense light using the
phytochrome system they will germinate.
15. (c) Spirogyra is an example for chorophyllous
thallophyte.
16. (b)
17. (d) When a gene masks the expression of another
non-allelic gene, this effective gene is called
epistatic gene. And the interaction factor is known
as epistatic factor
18. (a) A sheath-like structure found in a plant seed
that connects the coleoptile to the primary root
and acts as a protective covering enclosing the
plumule and radicle.
19. (a) Cell theory is not applicable for viruses. It
requires living host for its survival.
20. (c)
21. (c) The transfer of information from RNA to DNA
or the reverse of normal transcription is known
as Reverse transcription. It occurs in retroviruses
(HIV), eukaryotes etc.
22. (a) Palindromic sequence are sequence of base
pairs that reads same on the two strands when
orientation of reading is kept the same.
23. (b) Vessels of xylem are devoid of nucleus.
24. (b) Fungi is growing on potato dextrose agar
containing petriplate.
25. (a) Electron transport chains are used for
extracting energy via redox reactions from
sunlight in photosynthesis or, such as in the case
of the oxidation of sugars, cellular respiration.
In eukaryotes, an important electron transport
chain is found in the inner mitochondrial
membrane where it serves as the site of oxidative
phosphorylation through the use of ATP synthase.
It is also found in the thylakoid membrane of
the chloroplast in photosynthetic eukaryotes. In
bacteria, the electron transport chain is located in
their cell membrane.
26.(d) The tropical rain forest are more diverse
and highly densed with maximum productivity
(approximately 12000kcal/m^2 /yr).
