Question

Differentiate between

a. Bract and Bracteole
b. Pulvinus and petiole
c. Pedicel and peduncle
d. Spike and spadix
e. Stamen and staminode
f. Pollen and pollinium

Answer 1

1) Definition

* Bract is a reduced leaf-like structure situated at the base of the pedicel.

* Bracteole is a leaf-like structure present on the pedicel between bract and flower.


Summary

Criteria	Bract	Bracteole
Definition	Bract is a reduced leaf-like structure situated at the base of the pedicel.	Bracteole are usually paired leaf-like structures present between the bract and the flower.

Structure

* Pulvinus is the swollen leaf base.

* Petiole is the stalk of leaves which lies between leaf base and lamina.



Function

Pulvini are responsible for certain nastic movements in plants. The petiole holds the leaf to light and helps flutter in wind and exposes them to light.

Examples

The flowers of the leguminosae family have pulvinus while Hibiscus, rose have petioles.

Summary

Criteria	Pulvinus	Petiole
Structure	Pulvinus is the swollen leaf base	Petiole is the stalk of leaves which lies between leaf base and lamina
Function	Nastic movements	Holding the leaf to light and helping in fluttering movements
Example	Leguminosae family	Hibiscus, rose

3) Structure

The stalk of a single flower is called a pedicle.
The peduncle is the stalk/ axis of inflorescence bearing flowers



Summary

Criteria	Pedicel	Peduncle
Structure	The stalk of a single flower	The stalk/ axis of inflorescence bearing flowers

4) Structure

* Spike is a type of unbranched inflorescence bearing with
sessile flowers without pedicels.

* Spadix is a special type of inflorescence with a fleshy spike bearing usually unisexual, apetalous flowers with the upper part of the peduncle devoid of flowers and surrounded by large bracts (spathes).

Summary

Criteria	Spike	Spadix
Structure	Unbranched inflorescence bearing with sessile flowers without pedicels	Inflorescence with a fleshy spike bearing usually unisexual, apetalous flowers with the upper part of the peduncle devoid of flowers and surrounded by large bracts (spathes)

5) Fertility

* Stamen is a fertile male sex organ present in flowers
responsible for producing pollen grains.

* Staminode is rudimentary sterile male sex organ present in
flowers which donot produce pollens.


Summary

Criteria	Stamen	Staminode
Fertility	Stamen is a fertile male sex organ capable of producing pollens	Staminode is sterile male sex organ incapable of producing pollens

6) Definition

* Pollen is a male gametophyte bearing the male gametes.

* Pollinium is a group of pollen grains, usually the product of a single anther, held together by sticky secretions and are transported as a unit during pollination.


Summary

Criteria	Pollen	Pollinium
Definition	Male gametophyte bearing the male gametes	Group of pollen grains, usually the product of a single anther, held together by sticky secretions and are transported as a unit during pollination