Chapter 18 study guide

Question 1

How biologists use a classification system to name organisms and group them in a logical manner. They classify organisms and give them each a universally accepted name.

Answer 1

Taxonomy

Question 2

A naming system in which each species is assigned a 2 part scientific name. (1st name: genus, 2nd name: species name)

Answer 2

Binomial Nomenclature

Question 3

A group of closely related species

Answer 3

Genus

Question 4

Grouping organisms based on evolutionary history

Answer 4

Evolutionary Classification

Question 5

Characteristics that appear in recent parts of the lineage but not in its older members

Answer 5

Derived Characters

Question 6

A diagram that shows the evolutionary relationships among a group of organisms

Answer 6

Cladogram

Question 7

Uses DNA comparisons to estimate the length of time that 2 species have been evolving separately.

Answer 7

Molecular Clocks

Question 8

What Is the classification system developed by Linnaeus?

Answer 8

It’s called Taxonomy and its organised from smallest to largest. Each organism receives a universally accepted scientific name based on visible similarities and differences.

Question 9

What is the order of Linnaeus’s classification system?

Answer 9

1. Species
2. Genus
3. Family
4. Order
5. Class
6. Phylum
7. Kingdom
8. Domain

Question 10

What is evolutionary Classification? How Is it different from earlier classification?

Answer 10

It is the grouping of organisms based on their evolutionary history. It;s different from earlier classification because it’s based on evolutionary relationships and genetic data rather than visible similarities and differences.

Question 11

How are derived characters used to create and evolutionary lineage?

Answer 11

They indicate evolutionary changes that have occurred which is crucial when creating an evolutionary lineage.

Question 12

What is a molecular clock? How can it be used to mark the passage of evolutionary time?

Answer 12

A model that uses mutation rates and DNA to measure evolutionary time. Based on the DNA and mutations, you can figure out how similar or not similar certain species are and when they shared a common ancestor.

Question 13

What can scientists infer about two species that have many similarities in one gene?

Answer 13

They share a more recent common ancestor.