TANMAY SIR’S BIOLOGY PRIVATE TUITION
4. THE FLOWER
Q. Name the following:
1. A specialised shoot in which the leaves are modified into floral structures. Flower
2. A flower having all the four floral whorls. Complete flower / Perfect flower
3. A flower with any of the four whorls missing. Incomplete flower / Imperfect flower
4. A flower without a stalk. Sessile flower
5. The stalk that supports the flower. Pedicel
6. The tip of the flower stalk that expands to form a cup-shaped structure. Thalamus
7. The expanded tip of the pedicel / stalk bearing floral parts. Thalamus
8. A flower with both male and female reproductive whorl. Bisexual flower/
Hermaphrodite flower
9. A flower with either male or female reproductive whorl. Unisexual flower
10. A flower having only male reproductive whorl. Staminate flower
11. A flower having only female reproductive whorl. Pistillate flower
12. A flower in which both male and female reproductive whorl are lacking. Neuter
flower
13. A plant which has both male and female flower borne on the same plant. Monoecious
plant
14. Male and female flower grow on different plant. Dioecious plant
15. Parts that are directly involved in reproduction. Stamens and Carpels
16. Essential whorls of a flower. Androecium and Gynoecium
17. Parts which help a plant in reproduction. Sepals and petals
18. Non-essential / accessory whorls of a flower. Calyx and Corolla
19. A condition in which both sepal and petal are fused and undifferentiated. Perianth
20. When the perianth is coloured/non-green. Petaloid perianth
21. When the perianth is green. Sepaloid perianth
22. The first whorl of a flower. Calyx
23. Collective name of sepals. Calyx
24. Collective name of petals. Corolla
25. Collective name of stamens (male part). Androecium
26. Male reproductive part of a flower. Stamens
27. Collective name of carpels (female part). Gynoecium / Pistil
28. When male reproductive parts (stamens) are free. Polyandrous
29. When male reproductive parts (Stamens) are united in one group by their filaments.
Monadelphous stamens
30. When the filaments of stamens are arranged in two bundles. Diadelphous
31. When the filaments of stamens are arranged united in several groups. Polyadelphous
32. The tissue (region) of the ovary where ovules are attached. Placenta
33. The arrangement of ovules in an ovary. Placentation
34. A group of flowers arranged on a twig of a plant. Inflorescence
35. Nectar secreting cells at the base of the pistil / petals. Nectaries
36. The fragmented sweet liquid produced by petals/pistil to attract insects. Nectar
37. Female gamete of a flower. Egg cell in ovule
38. Male gamete of a flower. Pollen grains
39. A second series of sepals in shoe-flower. Epi-sepals
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
40. Collective term for second series of sepals in shoe-flower - Epicalyx
41. The outermost green whorl of a flower. Calyx
42. The second coloured whorl of a flower that attract insects for pollination. Corolla
43. A two-lobed or bilobed structure attached to the filament of a stamen. Anther
44. Four sacs present in male reproductive part. Pollen sac
45. Powdery particles present in pollen sac/anther. Pollen grains
46. The structure that develops into mature fruit. Ovary
47. The structure that develops into seeds. Ovules
48. The chambers present in the ovary of a flower. Locules
49. The tube formed by the fusion of filaments of stamens. Staminal tube
50. The terminal knob like structure of carpel. Stigma
51. The tubular slender stalk of carpel. Style
52. The swollen basal portion of carpel. Ovary
53. The round bodies present in the ovary of carpel/flower. Ovules
54. The cushion or swollen region in the ovary. Placenta
55. The structure that gives origin to ovules in a flower. Placenta
56. A leaf that develops in the axil of a flower. Bract
Q. Give examples for the following:
Example Point to Remember
Petaloid perianth Gul Mohur Gul Mohur is known as flame
of forest
Bract Bougainvillea
Nectaries Nasturtium
Bisexual flower Hibiscus
Unisexual flower Palm, Papaya
Staminate flower Palm, Papaya
Pistillate flower Palm, Papaya
Neuter flower Ray flower of sunflower Pistillate but sterile
Flower with epicalyx Hibiscus
Double whorl of corolla Poppy
Spiral whorl of corolla Water lily
Polyandrous stamens Petunia
Monadelphous stamens China rose, Cotton China rose has staminal tube
Diadelphous stamens Pea Pea has ten stamens; nine
stamens form a staminal tube
while one if free
Polyadelphous stamens Bombax
Monoecious plants Maize, cucumber, pumpkin
Dioecious plants Palm, Papaya
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Q. State the location and Function of the following:
STRUCTURE LOCATION FUNCTION
Pedicel It is the stalk of a flower To supports the flower
Thalamus Cup shaped structure present on The floral parts are borne on the thalamus
tip of the flower stalk
Calyx / Sepals Outermost green whorl / part of 1. Protect the young flower bud
a flower 2. When green they perform
photosynthesis
Corolla / Petals It is the second whorl of a flower 1. Petals attract insects for pollination
2. Also protect stamens and pistils
when the petals form a tube.
Androecium It is the third whorl of a flower It is the male reproductive whorl that
produces pollen grains
Anther It is attached to the extremity of Produces pollen grains
the filament of stamens
Pollen grain Present in the pollen sac of Produces two male (sperm) nucleus during
anther germination for double fertilisation.
Stigma The terminal knob-like part of Serves as the landing place for pollen
carpel during pollination
Style The tubular slender stalk of It is a passage for pollen tube to reach the
carpel ovule during fertilization
Ovary Swollen basal portion of carpel Develops into fruit after fertilization
attached to the thalamus
Ovule Attached to the placenta inside Contains the female egg cell that develops
the locules of ovary into seed after fertilization
Placenta The cushion or swollen region in It attaches the ovules to the ovary
the ovary of a flower
Q. Distinguish between the following:
FRUIT SEED
It is a ripened ovary. It is a ripened ovule.
It protects and helps to disperse the seeds. On germination it gives rise to a new plant.
Polypetalous Gamopetalous
Petals are free Petals are fused
Polysepalous Gamosepalous
Sepals are free Sepals are fused
Polyandrous stamens Polyadelphous stamens
Stamens are free Stamens are united in several groups
Monadelphous Diadelphous
Stamens are united in one group by their Filaments of stamens are united in two
filaments bundles
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Calyx Corolla
1. Protect the young flower bud 1. Petals attract insects for pollination
2. When green they perform 2. Also protect stamens and pistils when
photosynthesis the petals form a tube.
Complete flower Incomplete flower
Is one which contains all the four types of If one or more sets of floral structures are
floral structures. missing, the flower is called incomplete flower.
Example: Hibiscus Example: palm, papaya
Staminate flower Pistillate flower
A unisexual flower which contains only the A unisexual flower which contains only the
stamens is called the staminate flower. carpels is called the pistillate flower.
Bisexual flower Unisexual flower
A flower which contains both stamens and A flower which has only one of the
carpels reproductive parts (either stamen or carpel)
Q. Define / Explain
1. Bisexual flower: A flower which contains both stamens and carpels is called bisexual
or hermaphrodite flower. Example: Shoe-flower
2. Neuter flower: A flower in which both male and female reproductive organs are
lacking. Example: Ray florets of sunflower
3. Perianth: The petals and sepals are undifferentiated together called perianth
4. Bract: When a flower arises in the axil of a leaf-like structure, this structure is known
as bract.
5. Placentation: It is the manner in which the ovules are arranged in the plant ovary.
6. Inflorescence: It is the mode of arrangement of flowers on the axis of the plant.
Q. Redraw and Label the following parts.
1 – stigma
2 – style
3 – ovary
4 – thalamus
5 – sepal
6 – filament of stamen
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Q. Diagram Based question / draw neat and labelled diagram / Label the parts:
PARTS OF BISEXUAL FLOWER
Q. Figure show certain parts of a flower.
i. Label the parts.
Ans: 1 – Stigma, 2 – Style, 3 – Ovary, 4 – Ovule, 5 – Thalamus
ii. Which organ of a flower does the figure represent?
Ans: Carpel
iii. What is the collective name for such organs?
Ans: Gynoecium
iv. State the function of the structure 4.
Ans: Contains the female egg cell that develops into seed after fertilization.
Q. Figure show certain parts of a flower.
i. Which organ of a flower does the figure represent?
Ans: Stamen
ii. What is the collective name for such organs?
Ans: Androecium
iii. Are the contents of part in B male or female?
Ans: Male and called as pollen grains
iv. State the function of the anther.
Ans: Produces pollen grains
v. How many pollen sacs are present in each lobe of anther? – 2
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Q. The diagram shows cohesion of stamens.
A B C
i. What type of cohesion is shown in the figures?
Ans: A - Monadelphous, B – Diadelphous C – Polyadelphous
ii. Give examples in each of the three cases.
Ans: A – China rose, Cotton, B – Pea, C – Bombax
iii. What is the term use for if the stamens are free? Give one example.
Ans: Polyandrous. E.g.: Petunia
Q. Give Reasons
1. Maize plants are monoecious
Ans: As the plant bears both staminate and pistillate flower, maize plant are example of
monoecious plant
2. Ray florets of sunflower are pistillate but neuter flowers
Ans: Ray florets of sunflower contains female reproductive organs but they are sterile thus,
they are called as neuter flowers.
3. Salvia sepals are described as petaloid.
Ans: In salvia sepals are fused with petals and they are undifferentiated and forms a non – green
perianth, thus they are described as petaloid perianth
4. Some plants have nectaries.
Ans: Nectaries provide nectar, which attracts the insects for cross pollination.
5. Petals are brightly coloured.
Ans: Coloured petals attract insects for pollination.
6. The androecium of pea flower is diadelphous.
Ans: The filaments of pea are united in two bundles in which nine stamens form a staminal
tube while one is free.
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Q. The diagram shows type of floral part.
i. Name the floral part.
Ans: Sepal
ii. What is the collective name for such organs?
Ans: Calyx
iii. Mention the term use for (a), (b) and (c)
Ans: a – Polysepalous, b and c – Gamosepalous
iv. Name the term used for brightly coloured above structure.
Ans: Petaloid perianth
Q. The diagram shows type of floral part.
i. Name the coloured floral part.
Ans: Petal
ii. What is the collective name for
such organs?
Ans: Corolla
iii. Mention the term use for (A),
(B) and (C)
Ans: A – Polypetalous, B and C – Gamopetalous
iv. Name the term used for green coloured above structure.
Ans: Sepaloid perianth
Q. Identify the following flower and terms related to it:
Term: Bract
E.g.: Bougainvillea
Characteristics: Large, coloured bracts bear the flowers.
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TANMAY SIR’S BIOLOGY PRIVATE TUITION
Diagram to draw:
