Download Ch 12 Reproduction in flowering plants Practical 12.1

Ch 12 Reproduction in flowering plants
Practical 12.1 Examination of binary fission in bacteria
Results (p. 12-2)
Questions (p. 12-2)
1
2
2
Mitotic cell division.
3
a
Binary fission is a type of asexual reproduction.
b
Binary fission does not involve gametes.
The offspring are genetically identical to each other and to the parent.
4
bac
Practical 12.2 Examination and cultivation of a vegetative
propagating organ
Results (p. 12-5)
1
2
The iodine solution turns dark blue in colour.
Questions (p. 12-6)
1
Vegetative propagation is the process by which the vegetative parts of the
flowering plants develop into new plants.
2
Starch is stored in the tuber.
3
The buds of the tuber.
4
The swollen end of an underground stem.
5
The potato tuber becomes smaller because food stored in the tuber is used up for
the development of a new plant.
6
1
In spring, the buds use the food stored in the tuber to produce adventitious
roots and shoots.
2
In summer, some food made in the leaves is sent to the underground shoots
and stored. The ends of underground shoots swell and form new tubers.
3
In winter, the aerial shoots die and the new tubers remain dormant.
4
In the next growing season, each bud in the tubers may grow into a new plant.
Practical 12.3 Dissection and examination of a flower
Questions (p. 12-13)
1
Name
Function
Stigma
Receives pollen grains
Ovary
Contains ovules which carry female gametes
Flower stalk
Attaches the flower to the main stem of the plant
Style
Supports the stigma
Anther
Produces pollen grains which carry male gametes
Filament
Supports the anther
Petal
Protects the inner parts of the flower and attracts insects
Sepal
Protects the inner parts of the flower when it is a bud
2
a
carpel
stamen
b
corolla
calyx
3
The ovary develops into the fruit.
4
The flowers are bisexual because they have both stamens and carpels in the same
flower.
Practical 12.4 Examination of an insect-pollinated flower
and a wind-pollinated flower
Results (p. 12-17)
1
Part of the
flower
Feature
Gladiolus flower
Grass flower
Size
Large
Colour
(Result depends on the
Brown
specimen.)
Petal
Small
Way of attachment to
Firmly attached
the filament
Anther
Loosely attached
Position
Enclosed
flower
inside
the
Quantity
Small in number
Large in number
Texture
Rough and sticky
Smooth and dry
Size
Relatively smaller
Relatively larger
Position
Enclosed
flower
Texture
Sticky
Feathery
Present / Absent
Present
Absent
Hang outside the flower
Pollen grain
Stigma
Nectary
inside
the
Hang outside the flower
2
Gladiolus flower
Grass flower
Questions (p. 12-18)
1
Gladiolus is an insect-pollinated flower and grass is a wind-pollinated flower.
2
Gladiolus flower
Anther enclosed inside the flower. /
Large brightly coloured and scented
petal attracts insects and provides a
platform for them. / Sticky stigma curls
down to pick up pollen grains from the
insect. / Nectary secretes nectar to
attract insects. / Rough and sticky
pollen grains attach to the insect. (Any
three)
Grass flower
Feathery stigmas hang outside the
flower to catch pollen grains in the air.
/ Anther hangs outside the flower to
release pollen grains to the air. /
Filament is thin and flexible. / A large
number of light and smooth pollen
grains produced. (Any three)