(iii) Spore C(Chlamydospore) is found in Rhizopus and
Mucor.
(iv) Spore D(Ascospore) is characteristic of Class
Ascomycetes.
- (a): A – life cycle with zygotic meiosis
B – life cycle with gametic meiosis
(b) life cycle showing zygotic meiosis is found in dinoflagellates
and cellular slime moulds. life cycle showing gametic
meiosis is found in majority of protozoan protists, diatoms
and acellular slime moulds.
(c) Differences between life cycle with zygotic meiosis and life
cycle with gametic meiosis are as follows.
life cycle with zygotic
meiosis
life cycle with gametic
meiosis
- Zygote is the only diploid
structure in the life cycle.
All structures except
gametes are diploid.
- The dominant individual in
the life cycle is haploid hence
the life cycle is haplontic.
The dominant individual in
the life cycle is diploid hence
the life cycle is diplontic.
- Meiosis takes place at the
time of zygote germination.
Meiosis occurs only at the
time of gamete formation.
CHAPTER-3 : PlANT kINGDOm
- (d) 2. (d) 3. (a) 4. (b) 5. (b)
- (c) 7. (d) 8. (a) 9. (d) 10. (d)
- (c) 12. (c) 13. (b) 14. (c) 15. (c)
- False : The plant body of mosses is always leafy.
- True
- False : In Funaria, the male receptacle is surrounded by
rosette of divergent perigonial leaves.
- True 20. True 21. True 22. True
- True 24. True
- False : Endosperm development takes place before
fertilisation in gymnosperms, hence it is haploid.
- A-(iv), B-(i), C-(v), D-(ii), E-(iii), F-(vi)
- A-(i, vi), B-(iii, vii), C-(ii, iv), D-(v, viii), E-(ix, x)
- (A) : (i) – dorsiventral
(ii) – thallose
(iii) – foliose
(iv) – midrib
(v) – dichotomous
(vi) – Elaters
(vii) – peristome teeth
(B) Ferns are seed producing seedless vascular plants which
inhabit dry humid areas. They constitute the smallest largest
living group of primitive vascular plants. Ferns dominated
the earth in permian carboniferous period.
leaves are large and called ramenta fronds. Mature young
leaves show circinate ptyxis. younger parts of their stem,
leaves and petiole possess hairs called fronds ramenta.
- (b) 30. (a) 31. (a) 32. (a) 33. (b)
- (c) 35. (d) 36. (c) 37. (b) 38. (d)
- (a) : In the given life cycle of Chalmydomonas, phase I
represents asexual phase and phase II represents
sexual phase.
(b) X – Palmella stage
Y – Akinete
Z – Zoospores
In palmella stage, a large number of near naked cells
devoid of flagella lie inside a mass of mucilage. The stage
develops in response to toxic chemicals and unfavourable
water conditions.
- (a) : P is oogamy. In oogamy there is a fusion of large food
laden, non-flagellated female gamete and smaller motile
male gamete.
Q is anisogamy. In anisogamy, the fusing gametes are
structurally similar but differ in size and behaviour. One of
the two gamete is larger called macrogamete or female
gamete and the other is smaller, termed microgamete or
male gamete.
R is isogamy. In isogamy, both the fusing gametes are
morphologically and physiologically similar. They may be
flagellated or non-flagellated.
(b) S represents zygotic meiosis.
(c) Chlamydomonas exhibits haplontic life cycle. This can
be explained as follows:
The plant body is unicellular and haploid. It gives
rise to haploid gametes. Gametes fuse to produce
diploid zygote. Meiosis occurs at the time of zygote
germination. Zygote is the only diploid phase in its
life cycle.
CHAPTER-4 : ANImAl kINGDOm
- (a) 2. (a) 3. (d) 4. (b) 5. (a)
- (c) 7. (c) 8. (b) 9. (d) 10. (d)
- (a) 12. (b) 13. (c) 14. (b) 15. (d)
- False : Coelenterates have tissue level of body
organisation.
- True 18. True
- False : Pseudometamerism is found in tapeworms whereas
true metamerism is characteristic of Annelida.
- True 21. True 22. True 23. True
- False : Euplectella is commonly known as “The Venus’
flower basket” whereas Cliona is commonly known as ‘The
Boring sponge’.
- True
- A-(ii), B-(i), C-(iv), D-(iii), E-(vi), F-(v)
- A-(i, vi), B-(ii, v), C-(iii,vii), D-(iv,ix), E-(viii, x)
