Chapter 23.2, Problem 1NV

Summary Introduction

To determine:

The definition of photoperiodism.

Classification of the given vocabulary term as type of flowering plant or a part of flowering plant.

Explanation of Solution

Photoperiodism is a physiological behaviour or reaction of the plant or any other organism to length of the sunlight or any other artificial source of light.

The given vocabulary terms can be differentiated as type of flowering plant and part of flowering plant as follows:

Type of flowering plant

Part of flowering plant

1. Day neutral plant: the plant, in which the flowering is not dependent on the amount of sunlight it receives. 2. Intermediate day plant: The plants that require around 12-14 hours of day light for flowering, which is more than a short-day plant and less than a long day plant. 3. Long day plant: Plants that require more than 14 hours of day light for flowering. 4. Short day plants: Plants that require less than 8 hours of day light for flowering.

1. Petal: It is the coloured part of the flower that helps in the attraction of the animals to the flower. It is a sterile tissue of flower. 2. Sepal: It is also known as calyx and it is a modified leaf encasing the flower, present below petals. 3. Stamen: male reproductive organs of the flower. 4. Pistil: female reproductive organs of the flower.