Chapter 54, Problem 1TY

Which of the following is probably the most important factor in the distribution of organisms in the environment?

1. a. light
2. b. temperature
3. c. salinity
4. d. water availability
5. e. pH

Summary Introduction

Introduction: A system formed with the help of interactions between organisms and their physical environment is known as the ecosystem. The impact of the environment on the distribution of species and the way the organisms are physiologically adapted to their environments is investigated under physiological ecology. Temperature, light, pH, salinity, and water availability are several non-living factors influencing the way organisms are distributed in an environment.

Answer to Problem 1TY

Correct answer: Temperature plays the most important role in distributing organisms in the environment. Hence, the correct answer is option b.

Explanation of Solution

Reason for correct answer:

Most living organisms are unable to regulate their body temperatures. Thus, the ecological distribution of these organisms depends upon the temperature of that particular geographical area. The temperature also affects the biological processes of an organism. Therefore, temperature plays a very prominent role in distributing the biological organisms in the environment.

Option b. is given as “temperature”.

Temperature regulates body temperature and affects biological functioning, thus playing a prominent role in deciding the distribution of flora and fauna in the environment. Hence, the correct answer is option b.

Reasons for incorrect answer:

Option a. is given as, “light”.

Sunlight plays an important role in the photosynthesis process of plants. The growth of the plants is affected when sufficient sunlight is not provided to them. Aquatic plants receive less sunlight as water acts as a barrier. Sunlight does not reach the plant species lying at the depth of the water, thereby affecting its growth. Thus, light does play an important role in the survival of organisms. However, the temperature is more important in deciding the distribution of living organisms. Hence, option a. is incorrect.

Option c. is given as, “salinity”.

The growth of plants in highly saline soils is inhibited due to high salt concentration. High salinity also affects osmosis in the organisms which are present in marine as well as freshwater environments. Thus, salinity does impact the survival of the biological organisms. However, temperature plays a prominent role in their distribution. Hence, option c. is incorrect.

Option d. is given as, “water availability”.

Water availability is important for the survival of biological organisms. Plants require water to perform photosynthesis and other living organisms also need water for normal functioning of their body. Thus, water is important for survival but temperature is the most necessary factor which decides the distribution of organisms in the environment. Hence, option d. is incorrect.

Option e. is given as, “pH”.

When the soil pH is about 6.5, soil nutrients are most readily available to plants. This makes the soil optimum for the growth and survival of plants. Thus, pH determines the survival of plants but temperature determines the geographical distribution of organisms. Hence, option e. is incorrect.

Hence, the options a., c., d., and e. are incorrect.

Conclusion

Thus, temperature is one of the most prominent factors determining the distribution of flora and fauna in the environment.