4C Diversity And Classification

Question 1

What is phylogeny?

Answer 1

The study of the evolutionary history of groups of organisms. It tells us who’s related to who and how closely related they are.

Question 2

What is taxonomy?

Answer 2

The science of classification, involving naming organisms and organising them into groups.

Question 3

How do phylogeny and taxonomy interlink?

Answer 3

Scientists now take into account phylogeny when classifying organisms, and group organisms according to their evolutionary relationships.

Question 5

Define taxon, and taxa.

Answer 5

Taxa are the 8 levels of groups used to classify organisms.

Each group is called a taxon.

Question 6

Name each group in the taxon.

Answer 6

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 7

Name the three domains.

Answer 7

Eukarya, Bacteria and Archaea.

Question 8

Describe the taxon of species.

Answer 8

Species are groups that contain only one type of organism. A species is a group of similar organisms able to reproduce to give fertile offspring.

Question 10

Describe how the taxa changes as you move down the hierarchy.

Answer 10

There are more groups at each level but fewer organisms in each group. The organisms in each group also become more closely related.

Question 11

What is the advantage of the binomial system?

Answer 11

It enables scientists to communicate about organisms in a standard way.

Question 12

What is courtship behaviour?

Answer 12

It is behaviour carried out by organisms to attract a mate of the right species. It can be performed by either the male or the female, or both.

Question 13

Give examples of simple courtship behaviours.

Answer 13

Releasing a chemical, using sounds, visual displays.

Question 14

Give examples of complex courtship behaviours.

Answer 14

Dancing, building.

Question 15

How is courtship behaviour ‘species specific’?

Answer 15

Only members of the same species will do and respond to that courtship behaviour.

Question 16

What is the advantage of courtship behaviour being species specific?

Answer 16

It allows members of the same species to recognise each other, preventing interbreeding and making reproduction more successful.

Question 17

What effect does clarifying relationships between organisms have?

Answer 17

This can lead to classification systems being updated.

Question 18

How is genome sequencing used to clarify evolutionary relationships?

Answer 18

Genome sequencing can be used to find the entire base sequence of an organisms DNA. The base sequences of different organism can be compared to see how closely related they are. Closely related species will have a higher percentage of similarity in their DNA base sequence.

Question 19

How can comparing amino acid sequences be used to clarify evolutionary relationships?

Answer 19

Proteins are made by amino acids. The sequence of amino acids in a protein is coded for by the base sequence in an organisms DNA. Related organisms have similar DNA sequences and so similar amino acid sequences in their proteins.

Question 20

How can courtship behaviour be used to classify organisms?

Answer 20

The more closely related species are, the more similar their courtship behaviour.

Question 21

Describe the binomial system used for classification.

Answer 21

All organism are given an internationally accepted name in Latin that has two parts. The first part is the genus and has a capital letter. The second part is the species name and is written in lowercase italic.