Definitions [5]
Definition: Flower
A modified, compressed reproductive shoot of angiosperms bearing sepals, petals, stamens, and carpels, meant for sexual reproduction, is called a flower.
Definition: Thalamus (Receptacle)
The swollen terminal part of the pedicel on which all floral whorls are arranged is called the thalamus or receptacle.
Definition: Perianth
When calyx and corolla are not differentiated, the floral envelope is called the perianth.
Definition: Tepals
Individual members of the perianth are called tepals.
Definition: Whorl
A circular arrangement of floral organs at the same level on the thalamus is called a whorl.
Key Points
Key Points: Types of Flowers
| Basis of Classification | Type | Key Features | Examples |
|---|---|---|---|
| Presence of whorls | Complete | All four whorls present | Hibiscus, Mustard |
| Presence of whorls | Incomplete | One or more whorls absent | Maize, Papaya |
| Essential whorls | Neuter | Androecium and gynoecium absent | Ray florets of sunflower |
| Sex organs | Perfect (Bisexual) | Both androecium and gynoecium present | Hibiscus, Mustard |
| Sex organs | Imperfect (Unisexual) | Either androecium or gynoecium present | Papaya, Cucumber |
| Distribution of sex | Monoecious | Male and female flowers on same plant | Maize, Cucurbits, Coconut |
| Distribution of sex | Dioecious | Male and female flowers on different plants | Papaya, Date palm |
| Distribution of sex | Polygamous | Bisexual and unisexual flowers on same plant | Cotton, Sunflower |
| Position of ovary | Hypogynous | Ovary superior | Mustard, Tomato |
| Position of ovary | Perigynous | Ovary semi-inferior | Rose, Peach, Strawberry |
| Position of ovary | Epigynous | Ovary inferior | Cucumber, Apple |
Key Points:
| Part of Flower | Whorl Type | Main Components | Function |
|---|---|---|---|
| Calyx | Accessory whorl | Sepals | Protect inner floral parts |
| Corolla | Accessory whorl | Petals | Attract insects for pollination |
| Androecium | Essential whorl | Stamens (filament + anther) | Male reproduction; pollen formation |
| Gynoecium | Essential whorl | Carpels (stigma, style, ovary) | Female reproduction; seed and fruit formation |
