Biological Science (6th Edition)
Biological Science (6th Edition)
6th Edition
ISBN: 9780321976499
Author: Scott Freeman, Kim Quillin, Lizabeth Allison, Michael Black, Emily Taylor, Greg Podgorski, Jeff Carmichael
Publisher: PEARSON
bartleby

Concept explainers

bartleby

Videos

Textbook Question
Book Icon
Chapter 27, Problem 1TYK

Why are protists considered paraphyletic?

a. They include many extinct forms, including lineages that no longer have any living representatives.

b. They include some but not all descendants of their most recent common ancestor.

c. They represent all of the descendants of a single common ancestor.

d. Not all protists have all of the synapomorphies that define the Eukarya, such as a nucleus.

Expert Solution & Answer
Check Mark
Summary Introduction

Introduction:

A protist refers to any eukaryotic organism that has a cell with distinct nucleic acids and other membrane-covered structures. They do not form a clade or a natural group.

Answer to Problem 1TYK

Correct answer:

Therefore, protists are considered paraphyletic as this organism group includes only the most recent common ancestors as their descendants.

Explanation of Solution

Explanation/justification for the correct answer:

Option (b) is given as the protists include only some descendants of their recent common ancestors. The protists are the unicellular eukaryotes. This group of organisms is simple, but very diverse. These organisms do not have common ancestors. They possess different cellular structures, varying life cycles as well as different locomotion modes. They possess characteristics of plants or animals or both. Hence, Option (b) is correct.

Explanation for incorrect answer:

Option (a) is given as they involve extinct forms including the lineages that do not have any living representatives. After studying different protists at the molecular level, it has been found that they do not have common ancestors. The protists have characteristics of the descendants of some of their recent common ancestors. So, it is a wrong answer.

Option (c) is given as they show all the descendants of a single common ancestor. The taxa, which represents the protists does not include all descendants of all of their ancestors. This means that they are paraphyletic and not monophyletic. So, it is a wrong answer.

Option (d) is given as not all protists consist of synapomorphies, which describe the eukarya like the nucleus. Therefore, the protists are paraphyletic because they include only some descendants of a single common ancestor. They do not include lineages that no longer have any living representatives. The protists are those eukaryotes that are neither animals, plants, nor fungi, but they all possess a well-defined nucleus. So, it is a wrong answer.

Hence, options (a), (c), and (d) are incorrect.

Conclusion

Therefore, it can be concluded that the protists are known as paraphyletic because they involve some descendants of their recent common ancestor.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Do cats fly without wings ?
Luke recently moved to a new apartment and wants to grow houseplants but isn't sure which room will be the best fit for them. Apply your knowledge of the scientific method to recommend a strategy for Luke to follow when determining the ideal location for houseplants in his new apartment.
A farmer has noticed that his soybean plants produce more beans in some years than others. He claims to always apply the same amount of fertilizer to the plants, but he suspects the difference in crop yield may have something to do with the amount of water the crops receive. The farmer has observed that the soybeans on his farm usually receive between 0 to 0.5 inches of water per day, but he is unsure of the optimal average daily amount of water with which to irrigate. 1. State a question that addresses the farmer’s problem 2. Conduct online research on “soybean crop irrigation" and record a brief summary of the findings  3. Construct a testable hypothesis and record i 4. Design an experiment to test the hypothesis and describe the procedures, variables, and data to be collected  5. What is the purpose of a control group in an experiment? What would the control groups be for each of your designed experiments in this exercise? 6. Describe the data that would be recorded in each of the…
Knowledge Booster
Background pattern image
Biology
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Biology (MindTap Course List)
Biology
ISBN:9781337392938
Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg
Publisher:Cengage Learning
Text book image
BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)
Biology
ISBN:9781305967359
Author:STARR
Publisher:CENGAGE L
Text book image
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
Text book image
Biology: The Dynamic Science (MindTap Course List)
Biology
ISBN:9781305389892
Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan
Publisher:Cengage Learning
Text book image
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Text book image
Aquaculture Science
Biology
ISBN:9781133558347
Author:Parker
Publisher:Cengage
Bacterial Endospore Formation -Biology Pundit; Author: Biology Pundit;https://www.youtube.com/watch?v=6_sinRhE8zA;License: Standard YouTube License, CC-BY
Taxonomy of Bacteria: Identification and Classification; Author: Professor Dave Explains;https://www.youtube.com/watch?v=8IJRzcPC9wg;License: Standard YouTube License, CC-BY