Species and Taxonomy

Question 1

What is the concept of a species?

Answer 1

They are capable of breeding to produce living, fertile offspring, therefore able to produce more offspring, meaning that when species reproduce sexually, any of the genes of its individuals can be combined with any other.

Question 2

Why is the naming of species known as the binomial system?

Answer 2

Organisms are identified as two names.

Question 3

What are the features of the binomial system?

Answer 3

• Universal system based on Latin or Greek names
• Generic name, denotes the genus to which the organism belongs.
• Specific name, denotes the species to which the organism belongs.

Question 4

Why does courtship behaviour need to enable individuals to recognise a member of their own species?

Answer 4

Ensure mating takes place with members of the same species in order to produce fertile offspring

Question 5

Why does courtship behaviour need to enable individuals to identify a mate that is capable of breeding?

Answer 5

Both partners need to be sexually mature, fertile and receptive to mating

Question 6

Why does courtship behaviour need to enable individuals to form a pair bond?

Answer 6

To lead to breeding success and bringing up of offspring

Question 7

Why does courtship behaviour need to enable individuals to synchronise mating?

Answer 7

Takes place when there is a maximum possibility of the sperm and egg meeting

Question 8

Why does courtship behaviour need to enable individuals to become able to breed?

Answer 8

by bringing a member of the opposite sex into a physiological state that allows breeding to occur.

Question 9

Why is courtship behaviour used by males?

Answer 9

To determine whether the female is receptive at this stage and is fertile.

Question 10

What is the grouping of organisms known as?

Answer 10

Classification

Question 11

What are the two main forms of biological classification?

Answer 11

Artificial classification and Phylogenetic Classification

Question 12

What is Artificial Classification?

Answer 12

Divides organisms according to differences that are useful at the time, including colour, size, number of legs, leaf shape etc. These are described as ANALOGOUS characteristics where they have the same function but do not have the same evolutionary origins.

Question 13

What is Phylogenetic Classification?

Answer 13

• Based upon evolutionary relationships between organisms and their ancestors.
• Classifies species into groups using shared features derived from their ancestors.
• Arranges the group into a hierarchy, in which groups are contained within larger composite groups with no overlap.

Question 14

What are the three Taxonomy DOMAIN groups?

Answer 14

Bacteria, Archaea (prokaryotes) and Eukarya

Question 15

What are Bacteria?

Answer 15

A group of single celled prokaryotes

Question 16

What are the features of bacteria?

Answer 16

• Absence of membrane-bound organelles.
• Unicellular
• 70S ribosomes
• Cell walls present mate of murein
• Single loop of DNA made up of nucleic acid but no histones

Question 17

What are Archaea?

Answer 17

Group of single-celled prokaryotes that were originally classified as bacteria which they resemble in appearance.

Question 18

How are Archaea different to Bacteria?

Answer 18

• Genes and protein synthesis more similar to eukaryotes.
• Membranes contain chains of fatty acid and glycerol connected by ester bonds.
• No murein in cell walls
• More complex RNA polymerase.

Question 19

What are Eukarya?

Answer 19

Organisms made up of one or more eukaryotic cell.

Question 20

What are the features of Eukarya?

Answer 20

• Membrane bound organelles such as mitochondria and chloroplasts.
• membranes containing fatty acids and glycerol linked by ester bonds.
• Not all cells have cell walls and they do not possess murein.
• ribosomes are larger (80s) than in bacteria and archaea.

Question 21

How are the taxonomic species of groups broken down?

Answer 21

Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 22

What is Phylogeny?

Answer 22

Hierarchal order of taxonomic ranks is based upon evolutionary line of descent of the group members. The evolutionary relationship is known as phylogeny.

Question 23

How are phylogenetic relationships represented?

Answer 23

In a phylogenetic tree, with the oldest species at the bottom and most recent ones represented by the ends of branches.