Chapter 11, Problem 35A

Summary Introduction

To identify:

The temperature at which the wing length is greatest.

Introduction:

The environment also has an effect on phenotype of an individual. The tendency to develop heart disease can be inherited but environmental factors like diet and exercise also contribute to the occurrence of disease. Sunlight, water and temperature are some environmental factors that affect an organism’s phenotype.

Answer to Problem 35A

The temperature at which the wing length is greatest is 31⁰C.

Explanation of Solution

As per the given graph, the wing length of male fly remains almost constant between temperatures 18⁰C to 26⁰C. After 26⁰C, wing length increases slowly and then after 29⁰C, there is a sharp increase in length of wings. At 31⁰C, the wing length of male fly is greatest.

The wing length of female fly increases gradually with increase in temperature up to 30⁰C and then there is a sudden increase in length between 30⁰C and 31⁰C. The wing length of male fly is more than wing length of female fly at 31⁰C.