The Flower

Both A and R are False.

Reason — Many angiosperms bear incomplete flowers that lack one or more floral parts. For example, unisexual flowers of papaya (dioecious) or maize (monoecious). Hence, the assertion is false.
Because incomplete flowers exist, it is not true that every angiosperm flower possesses all four whorls (calyx, corolla, androecium, gynoecium). Hence, reason is false.

Both A and R are False.

Reason — Dioecious plants do not bear hermaphrodite flowers (flowers with both male and female organs). Instead, male and female flowers are on separate plants. In monoecious plants, stamens and pistil are on the same plant.

A is True and R is False.

Reason — When stamens are united by their filaments into one bundle, it is called a monadelphous condition. Pea has diadelphous stamens (united into two bundles). Bombax has polyadelphous stamens (united into more than two bundles).

A is False and R is True.

Reason — The most attractive and colourful part of a flower is the corolla (petals), not the calyx. The calyx is made up of sepals. It protects the young flower bud. When green, it can also perform photosynthesis.

Both A and R are True.

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

(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.

Large colourful bracts

Reason — In Bougainvillea, the flower arises in the axil of bracts, which become colourful.

It has all the four whorls

Reason — A flower with all the four whorls present, is known as complete flower.

Ovary

Reason — Ovary is the swollen basal portion of the gynoecium that develop into fruit.

Ovule

Reason — Ovule grows to form 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.

Pedicel

Reason — Stalk of flower is called Pedicel.

Stigma

Reason — Stigma is the top most portion of carpel that receives pollen grains.

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.

Polyandrous

Reason — When the stamens are free, such condition is called Polyandrous.

Hermaphrodite

Reason — The flower which contains both stamens and carpels is called a bisexual or hermaphrodite flower.

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.

Palak

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

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.

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.

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

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.