Chapter 27, Problem 9STP

Summary Introduction

Introduction:

Ferns are the vascular plants that belong to the Kingdom Plantae. They reproduce through spores. They do not possess seeds or flowers. They are used as food but they do not have major economic importance.

Answer to Problem 9STP

Correct answer:

The correct answer is option (B) 12.

Explanation of Solution

Explanation/justification for the correct answer:

Option (B) 12. The sporophyte plant is diploid. As it undergoes a reduction in cell division, it will produce a haploid number of spores. Therefore, the number of chromosomes in spores will be half of the number of fronds of fern. So, this is the correct answer.

Explanation for incorrect answer:

Option (A) 6. The number of chromosomes in spores goes half of the number of fronds of fern because of the reduction in cell division. So if the number of chromosomes of the frond of the fern is 24, the number of chromosomes of spores will be 12. Therefore, this is an incorrect option.

Option (C) 24. As the fern is diploid and it undergoes reduction cell division and produces a haploid number of spores. Therefore the number of chromosomes in spores will not be the same but half as in the frond of ferns. So, this is an incorrect option.

Option (D) 48. As the sporophyte plant goes reduction cell division, it produces a haploid number of spores. The chromosome in the frond of ferns is given as 24 so the half of 24 is 12 which is the number of chromosomes in spores. So, this is an incorrect answer.