Chapter 11, Problem 1SQ

Summary Introduction

Introduction:

Mitosis refers to a nuclear division mechanism that maintains the chromosome number. When a nucleus divides by mitotic cell division, each new nucleus has the same chromosome number as the parent cell.

Answer to Problem 1SQ

Correct answer:

Mitosis and cytoplasmic division play an important role in both asexual reproduction of single-celled eukaryotes and growth and tissue repair in multicelled organisms. Hence, the correct answer is option e.

Explanation of Solution

Reason for correct answer:

Option e. is given as, “both a and b.”

In multicelled species, mitosis and cytoplasmic division are the basis of increases in body size and tissue remodeling, as well as ongoing replacements of damaged cells. Mitosis and cytoplasmic division are also part of asexual reproduction of single-celled eukaryotes. Hence, option e. is correct.

Reason for incorrect answer:

Option a. is given as, “asexual reproduction of single-celled eukaryotes.”

Although mitosis and cytoplasmic division are part of asexual reproduction, they also play an important role in growth and tissue remodeling during development in multicelled organisms. Hence, option a. is incorrect.

Option b. is given as, “growth and tissue repair in multicelled species.”

Mitosis and cytoplasmic division are the basis of growth and tissue remodeling in multicelled-organisms. Mitosis and cytoplasmic division are also part of asexual reproduction. Hence, option b. is incorrect.

Option c. is given as, “gamete formation in bacteria and archaea.”

Gamete formation in bacteria and archaea usually take place by binary fission. Hence, option c is incorrect.

Option d. is given as, “sexual reproduction in plants and animals.”

Meiosis is the basis of sexual reproduction in plants and animals. Hence, option d is incorrect.

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

Conclusion

Mitosis and cytoplasmic division are the basis of both asexual reproduction of single-celled eukaryotes and growth in multicelled organisms. Thus, the correct option is e.