Chapter 21, Problem 1FIB

Summary Introduction

Introduction:

Green algae are the most diverse group of algae. The green algae contain two forms of chlorophyll, which they use to capture light energy to produce sugar. The vascular system is also known as a circulatory system in plants two types of tissues are presents: xylem and phloem. Alteration of generation is used to describe a process in the life cycle of some eukaryotes.

Answer to Problem 1FIB

Correct answer:

Scientists hypothesize that the ancestor of plants were green algae. There are two major types of plants; those that lack conducting cells are called nonvascular plants and those with conducting cells are called vascular plants. All plants produce multicellular embryos and exhibit a complex life cycle called alternation of generation.

Explanation of Solution

It was earlier assumed that higher plants evolved from blue-green algae because both the species have chloroplast “a green color pigment” that helps them in energy conversion. Two type’s plants are present one that has xylem and phloem for the transportation of water and nutrients called tracheophytes other that do not have xylem and phloem called bryophytes.

Plant embryo is the part of a seed consisting of some precursor tissues of leaves and stems. Alteration of generation means the fluctuation between the haploid and diploid stages that occur in plants. It is also known as metagenesis alteration of sexual phase and an asexual phase in the life cycle of plants.

Conclusion

Algae are considered as the ancestor of all the land plants because of the presence of chlorophyll. Plants are differentiated on the basis of vascular tissue, some plants lack this vascular tissue.