Selina Concise Class 9 Biology Solution Chapter No. 4- ‘The Flower’ For ICSE Board Students.
A.)
1.)
Answer: Large colourful bract
A flower generated in the axil of a leaf like structure is a Bract. Generally, bracts are green like leaves and in some cases such as Bougainvillea there is large colourful bract present.
2.)
Answer:d) It has all the four whorls
When all the four types of whorls are present in the flower then it is said to be perfect or complete flower.
3.)
Answer:c) Ovary
In the flower, ovules become seeds in the mature fruit and Ovary is the part of flower which gives rise to the fruit.
4.)
Answer:c) Ovule
In the mature fruits the ovule turns into seed. The ovule part of the flower gives rise to the seed.
5.)
Answer: d) Androecium and gynoecium
The essential whorls of flower are those parts that are directly concerned with reproduction. So the male part androecium and female part is gynoecium and these takes part in the reproduction. For this reason option d) is correct.
B.)
Column A | Column B (Answers) |
Polyadelphous | iv) Bombax |
Pollen grains | v) Pollen sac |
Free petals | i)Polypetalous |
Non-essential | ii) Calyx, corolla |
Sweet fragrant fluid | iii) Nectar |
C.)
1.)
Answers:
a)
Incomplete flower- When one or more floral whorls sets are missing in the flower, then the flower is called as Incomplete or imperfect flower.
b)
Staminate flower- If a unisexual flower contains only the male part which is stamens, then it is called as Staminate or male flower.
c)
Pistillate flower- If a flower contains only the carpels, then the flower is called as Pistillate or female flower.
d)
Bisexual flower- When a flower contains both male stamens and female carpels, then it is said to be Bisexual or hermaphrodite flower.
2.)
a)
Flower | Inflorescence |
The flower has pedicel and it is stalk of the flower.
Example is Sunflower |
The inflorescence has peduncle and it is stalk of the inflorescence.
Example is Wisteria sinensis |
b)
Petals | Petaloid sepals |
The flowers containing petals also have separate set of sepals. | These are modified sepals which looks like petals. |
c)
Polyandrous | Polyadelphous androecium |
If the stamens of the androecium are free then the condition is known as Polyandrous. | If the filaments of anther are united in the several groups then it is called as Polyadelphous. |
3.)
Answers
- a)
Placenta- The placenta is swollen part which is located on the ovary and it attaches the ovules to the wall of the ovary.
b)
Thalamus:A cup shaped thalamus is located at the tip of the stalk flower and it bears all the parts of the flower.
c)
Anther- Anther is located at the top of the filament of stamen and it produces pollen which forms the male gametes.
d)
Stigma-Stigma (is sticky knob) is located at the top of the pistil and is terminal knob like part. Functionally, it gives landing location for the pollen during pollination.
4.
Answers:
a)
The anther’s filaments are unites in two bundles that’s why the androecium of pea flower is Diadelphous.
b)
Ray florets of sunflower is an example of neuter flower and neuter flowers are the flowers which are lack of both male-female reproductive organs. Hence, ray florets of sunflower are neuters.
c)
Salvia sepals are red in color like petals and three sepals are united. They are also undifferentiated from the petals, because of this Salvia sepals are Petaloid.
D.)
1.)
Answer:
The polyandrous, monadelphous, diadelphous and polyadelphous are the four types of androecium found in the flowers. The stamens of flower are said to be free then it is called as polyandrous. The stamens which are united in one group by their filaments and only anthers will be free then it is called as monadelphous. The filaments which are united in two bundles are known as diadelphous.
The last type is polyadelphous. The filaments which are united into more than two groups in the flower then it is called as polyadelphous.
2.)
Answers:
a)
Monadelphous is a type of androecium found in China rose.
b)
Polyadelphous is the type of androecium found in Bombax.
c)
Diadelphous is a type of androecium found in Pea.
E.)
1.)
1)- Anther
2)- Filament
3)- Ovule
4)- Placenta
5)- Stigma
6)- Style
7)- Ovary
8)- Petals
9)- Sepals
10)- Thalamus
2.)
Answer:
a)
A figure represents the major organ of the flower which is ‘Stamen’. It collectively forms androecium.
b)
Male gametes are the contents of the pollen sacs in the figure B.
c)
The agents like wind insects and air are responsible for the contents of pollen sacs coming out. Also it leads to pollination in the flowers.
3.)
Answer:
A leaf like structure that flower arise in the axil is called as ‘Bract’. In some cases, bracts looks like green leaves and sometimes they are colourful. The flower are actually small in this case. Bracts are responsible for the attraction of insects which leads to pollination.
4.)
Answer:
Monadelphous- A flower’s anther which are fused into one group is known for monadelphous. Cotton and China rose are the examples of monadelphous.
Diadelphous- A flower’s anther filament which are fused into two groups are known for diadelphous and Pea is an example.
Polyadelphous- A filament of anther are fused in several groups are known as polyadelphous and Bombax is the example.