(a) At higher concentration of Mg2+, ribosomal subunits
get separated.
(b) Mg2+ is required for binding two subunits of ribosome.
(c) Ribosome may occur as monosomes or polysomes.
(d) Mg2+ do not play any role in the formation of ribosome.
- More ribosomes would be found in
(a) meristematic cells of plant
(b) parenchymatous cells of plant
(c) lignified cells of plant
(d) dead cells.
- Lampbrush chromosomes can be seen during
(a) diplotene stage (b) metaphase
(c) anaphase (d) zygotene stage.
- Specialised microbody that can be extracted from the
endosperm of germinating groundnut seed is
(a) ribosome (b) peroxisome
(c) lysosome (d) glyoxysome.
- Study the given table and identify A, B, C and D.
Organelle Function
Nucleolus A
Centriole B
C Cytoplasmic streaming, endocytosis
and exocytosis
D Provides sites for polypeptide synthesis
and protects newly synthesised
polypeptide from cytoplasmic enzymes.
(a) A - Transcription, B - Cytoskeleton formation,
C - Microtubule, D - Peroxisome
(b) A - Spindle formation, B - Cell plate formation,
C - Micro-filament,D - Mitochondria
(c) A - rRNA synthesis, B - Sensory organ,
C - Intermediate filament, D - Nucleus
(d) A - Stores nucleoproteins, B - Synthesise sperm tail,
C - Microfilament, D - Ribosome
- Which of the following is a characteristic of euchromatin?
(a) Inhibits crossing over
(b) Presence of active genes
(c) Distributed throughout the nucleoplasm
(d) Does not replicate
- Puffs or Balbiani rings in polytene chromosomes are sites
of
(a) DNA replication (b) translation
(c) transcription (d) both (a) and (c).
- Chloroplast ribosomes are
(a) 60S (b) 70S
(c) 55S (d) 80S.
18. Match column I with column II and select the correct option.
Column I Column II
A. Free ribosome (i) Endocytosis
B. Bound ribosome (ii) Synthesis of ribosomal
RNAs
C. Chloroplast (iii) Synthesise proteins to be
used inside the cell
D. Peroxisome (iv) Alcohol detoxification
E. Glyoxysome (v) Synthesise proteins for
transport
(vi) b-oxidation of fatty acids
(vii) Synthesise fatty acids
(a) A-(ii); B-(i); C-(vi); D-(vii); E-(iv)
(b) A-(iii); B-(v); C-(i); D-(vi); E-(iv)
(c) A-(v); B-(iii); C-(i); D-(iv); E-(vii)
(d) A-(iii); B-(v); C-(vii), D-(iv), E-(vi)
19. Nucleoproteins are synthesised in the
(a) nucleolus (b) nucleoplasm
(c) cytoplasm (d) nuclear membrane.
20. Microtubule : Tubulin :: Microfilament : ____.
(a) Keratin (b) Myosin
(c) Actin (d) Both (a) and (c)
21. Ribosomes in animal cells were discovered by
(a) Robinson (b) Brown
(c) Palade (d) Benda.
22. Chromosome with sub-terminal centromere is called
(a) telocentric (b) acrocentric
(c) submetacentric (d) acentric.
23. Oxysomes are present in
(a) peroxisomes (b) ribosome
(c) mitochondria (d) rough endoplasmic reticulum.
24. What is the common feature of chloroplast, chromoplast
and leucoplast?
(a) They are bound by double membrane and contain
photosynthetic pigments.
(b) They have thylakoids and grana.
(c) They store starch, proteins and lipids.
(d) They have the ability to multiply by binary fission.
25. Which of the following does not belong to cell inclusions?
(a) Reserve food (b) Secretory product
(c) Sap vacuole (d) Mineral matter
ANSWER KEY
- (d) 2. (b) 3. (b) 4. (d) 5. (b)
- (c) 7. (b) 8. (c) 9. (d) 10. (b)
- (a) 12. (a) 13. (d) 14. (d) 15. (b)
- (c) 17. (b) 18. (d) 19. (c) 20. (c)
- (c) 22. (b) 23. (c) 24. (d) 25. (c)
