The Flower

1. True
2. False
   Corrected statement — A flower typically has four floral Whorls.
3. True
4. True
5. True
6. True
7. True
8. False
   Corrected statement — Papaya is dioecious plant.

Large colourful bracts

Reason — In Bougainvillea, the flower arises in the axil of bracts, which become colourful.
Sepals are usually small, green, leaf-like structures. A nectary is the part that produces nectar to attract pollinators. Bougainvillea does have nectary. Bougainvillea’s actual petals are small and inconspicuous, not large or brightly colored.

It has all the four whorls

Reason — A flower with all the four whorls present, is known as complete flower.
Having corolla and calyx only, means missing reproductive parts. Having corolla and gynoecium only, means missing calyx and androecium. Having androecium and gynoecium only, means only reproductive parts, missing outer whorls.

Ovary

Reason — Ovary is the swollen basal portion of the gynoecium that develop into fruit.
Sepals protect the flower bud, do not form fruit. Petals attract pollinators. Stamens are male reproductive part which produce pollen.

Ovule

Reason — Ovule grows to form seed.
Ovary forms the fruit, not the seed. Placenta holds the ovules inside the ovary. Pollen grain contains male gametes but does not become the seed.

Androecium and gynoecium

Reason — The essential whorls of the flower are those that are directly concerned with reproduction. Androecium and gynoecium are the male and female reproductive parts of the flower, respectively.
Calyx and Corolla are accessory (non-essential) whorls. Stamen and ovary are parts of the essential whorls, not the whorls themselves. Epicalyx are non-essential structures.

Pedicel

Reason — Stalk of flower is called Pedicel.
Petiole is stalk of a leaf. Peduncle is main stalk of an inflorescence or a solitary flower (not individual flower stalk). Funicle is stalk attaching ovule to placenta inside the ovary.

Stigma

Reason — Stigma is the top most portion of carpel that receives pollen grains.
Style connects stigma to ovary; does not receive pollen. Ovary contains ovules; site of fertilization and seed formation. Ovules develop into seeds after fertilization.

Tepals

Reason — In some cases, the sepals and petals look very similar and cannot be differentiated from one another. They are called tepals and collectively known as perianth.
Sepals is only one whorl, not the whole perianth. Bracts modified leaves, not part of perianth. Petals only corolla, not the entire perianth.

Polyandrous

Reason — When the stamens are free, such condition is called Polyandrous.
In Polyadelphous, stamens are fused into more than two groups. In Polysepalous, sepals are free from each other. In Polypetalous, petals are free from each other.

Hermaphrodite

Reason — The flower which contains both stamens and carpels is called a bisexual or hermaphrodite flower.
Unisexual flower has either stamens or carpels, not both. Pistillate flower is a female flower. So, carpels are present in it but stamens are absent. Staminate flower is a male flower. So, stamens are present but carpels are absent in it.

P — Tepals, Q — Stamens

Reason — When calyx and corolla are indistinguishable, they are known as tepals. Group of tepals is known as perianth. Group of stamen is known as androecium.
Carpels belong to gynoecium, not perianth. Petals belong to the corolla.

Palak

Reason — Dioecious plants have male and female flowers on separate plants. Palm and Papaya are examples of dioecious plants.
Maize and Pumpkin are examples of monoecious plants where male and female flowers grow on the same plant.

(1) and (2)

Reason — Flowering plants have different types of inflorescence. Flowers do not always arise from the apical bud; they can also arise from axillary buds.
Flowers may arise from the axillary buds or terminal buds depending on the plant type. Flowers appear at almost the same height forming a cluster.

The terminal knob-like part of the pistil is Stigma which is covered with hairs or with glandular papillae. Style is the tubular slender stalk which connects the uppermost part to the lowest part of the pistil. Ovary is the swollen basal portion composed of one or many Carpels fused together. Ovary contains one or more rounded bodies, the Ovules which are attached to the wall of the ovary with Placenta.

1. Calyx, Corolla, Androecium, Gynoecium
2. Staminate flowers, Pistillate flowers
3. Anther and Filament
4. Stigma, Style, Ovary
5. Monadelphous, Diadelphous, Polyadelphous

1. Maize, Cucumber
2. Palm, Papaya
3. Palm, Papaya
4. Hibiscus, Rose

1. The floral parts are borne on the thalamus in four whorls.
2. The collective name of petals is corolla .
3. Calyx and corolla are accessory whorls of the flower.
4. Placenta attaches the ovules to the wall of the ovary.
5. The sweet fragrant liquid of flowers is termed as nectar.

1. Corolla
2. Androecium
3. Polyandrous
4. Petaloid
5. Ovary

1. China rose — The type of androecium found is Monadelphous.
2. Bombax — The type of androecium found is Polyadelphous.
3. Pea — The type of androecium found is Diadelphous.

1. Incomplete flower — A flower is said to be an incomplete flower if one or more sets of floral whorls are missing. E.g. American Elm.

2. Staminate flower — A unisexual flower which contains only the stamens is called the male or staminate flower. E.g. Eastern Cottonwood.

3. Pistillate flower — A flower which contains only the carpels is called the female or pistillate flower. E.g. Date Palm.

4. Bisexual flower — A flower which contains both stamens and carpels is called a bisexual or hermaphrodite flower. E.g. Rose.

(a) Difference between flower and inflorescence:

(b) Difference between petals and petaloid tepals:

1. Flower is specialized shoot in which the leaves are modified into floral structures.
2. Inflorescence is the mode of arrangement of flowers on the axis of a plant.
3. The manner of attachment of ovules to the wall of the ovary is called Placentation.
4. When a flower arises in the axil of a leaf-like structure, this structure is called Bract.
5. An additional whorl around the calyx of a flower is called Epicalyx.

1. Placenta:
   Location — Cushion or swollen region in the ovary.
   Function — Attaches the ovules to the wall of the ovary.

2. Thalamus:
   Location — Tip of the flower stalk.
   Function — Bears all the parts of the flower.

3. Anther:
   Location — Part of the stamen.
   Function — Produces male gametes or pollen grains.

4. Stigma:
   Location — Terminal knob like part of the pistil.
   Function — Serves as the landing place for pollen grains during pollination.

(a) Difference between Monoecious and Dioecious plants:

(b) Difference between Perfect and Imperfect flowers:

(c) Difference between Unisexual and Bisexual flowers:

(d) Difference between Essential and Non-essential whorls of a flower:

(e) Difference between Polyandrous and Polyadelphous stamens:

(a) It is because the filaments of anthers are united in two bundles. Nine out of ten stamens in a pea plant form a staminal tube. The tenth is free.

(b) Ray florets of sunflower are described as neuters because both male and female reproductive structures are lacking.

(c) Sepals of the salvia are petaloid as 3 sepals are red in colour and united as petals. Therefore, they are not differentiated from the petals.

When a flower arises in the axil of a leaf like structure, this structure is known as bract. It may be green like leaves or at times they are coloured.

The function of bracts is to protect the flower during its development and maturation. They may cover the flower bud, providing a shield against physical damage, excessive light, or harsh weather conditions. Colourful bracts can help attract pollinators to the flower.

1. Monadelphous — Stamens are united in one group by their filaments. Only anthers are free. E.g. China Rose.

2. Diadelphous — The filaments are united in two bundles. E.g. Pea.

3. Polyadelphous — The filaments are united in several groups. E.g. Bombax.

The parts labelled from 1 to 10 are as follows:

1. Anther
2. Filament
3. Ovule
4. Placenta
5. Stigma
6. Style
7. Ovary
8. Petal
9. Sepal
10. Receptacle / Thalamus

(a) Figure A represents stamen. Stamens collectively form Androecium.

(b) Contents of the pollen sacs in B, are male gametes.

(c) The contents of the pollen sacs would come out through agents like air, wind, insects leading to pollination in flowers.

• A → Polyandrous. e.g. Petunia.
• B → Monadelphous. e.g. China Rose.
• C → Diadelphous. e.g. Pea.
• D → Polyadelphous. e.g. Bombax.

Below is the labelled diagram of male (♂) and female (♀) reproductive organs of a flower:

(c) The collective name of male reproductive organs is Androecium and female reproductive organs is Gynoecium.

(d) Pollen grains are produced in male reproductive organs and Ovules are produced in female reproductive organs.

(e) Ovary develops into fruit and Ovules develop into seeds, respectively.

(a) Polysepalous calyx

(b) Gamosepalous calyx

(c) Polypetalous corolla

(d) Gamopetalous corolla

(e) Bracteate flower

A is false but R is true.

Reason — Not all flowers of angiosperms are complete or perfect. A complete flower has all the four floral whorls — calyx, corolla, androecium and gynoecium. A perfect flower is bisexual, that is, it possesses both androecium and gynoecium. In angiosperms, some flowers are unisexual, such as those of papaya and maize, and therefore they are not perfect. Some flowers may also lack one or more whorls and are thus incomplete. Hence, Assertion (A) is false.

The Reason (R) is true because angiospermic flowers may be either unisexual or bisexual.

Therefore, A is false but R is true is the correct option.

A is true but R is false.

Reason — In dioecious plants, the male and female unisexual flowers are borne on different plants. Therefore, A is true.
R is false because staminate and pistillate flowers occurring on the same plant at different positions is a characteristic of monoecious plants, not dioecious plants.

Therefore, A is true but R is false is the correct option.

A is True and R is False.

Reason — A is True because when stamens are united by their filaments into one bundle, it is called a monadelphous condition.
R is False as Pea has diadelphous stamens (united into two bundles). Bombax has polyadelphous stamens (united into more than two bundles).

Therefore, A is true but R is false is the correct option.

Both A and R are true but R is not the correct explanation of A.

Reason — The calyx is the outermost whorl of a flower, so A is true.
R is also true because the calyx consists of sepals, which protect the young flower bud and may also perform photosynthesis when green.
However, this does not explain why the calyx is the outermost whorl of the flower.

Therefore, Both A and R are true but R is not the correct explanation of A is the correct option.

Both A and R are true and R is the correct explanation of A.

Reason — A is true as calyx and corolla are called non-essential or accessory floral parts because they do not directly take part in reproduction (unlike androecium and gynoecium).
R is true as the calyx protects the flower bud and corolla attracts insects for pollination, which aids reproduction.

Therefore, Both A and R are true and R is the correct explanation of A is the correct option.

(a) No, these colourful structures are not epipetals. They are bracts. The term epipetalous refers to stamens that are attached to petals, whereas in Bougainvillea the coloured structures are modified leaf-like parts surrounding the flower.

(b) Bracts are modified leaf-like structures present at the base of a flower or inflorescence. They may sometimes become brightly coloured.

(c) Three colours seen in Bougainvillea bracts are:

1. Pink
2. Purple
3. Red

(d) These structures become colourful due to the presence of pigments such as anthocyanins. Their important role is to attract insects and other pollinators for pollination, since the actual flowers are small and inconspicuous.

(e) If any other part of the flower becomes petal-like or colourful, the technical term is petaloid.