Topic 4C: Diversity and Classification

Question 1

Define phylogeny

Answer 1

• The study of the evolutionary history of groups of organisms

Question 2

What are phylogenetic trees and what do they show?

Answer 2

• Show common ancestor - each branch
• More closely related organisms have a more recent common ancestor

Question 3

Define taxonomy

Answer 3

• The science of classification

Question 4

How is taxonomy used?

Answer 4

• Organises organisms into groups - taxa
• These are arranged into a hierarchy of largest to smallest groups
• Organisms can only belong to one group in each level with no overlap

Question 5

What are the groups used?

Answer 5

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

Question 6

What is the binomial system?

Answer 6

• Organisms known by their genus and species name

Question 7

Why is the binomial system used?

Answer 7

• To allow standard communication regardless of language

Question 8

How are binomial names written?

Answer 8

• Italics if typed
• Underlined if handwritten
• Genus has capital letter
• Species has lowercase letter

Question 9

What are courtship behaviours?

Answer 9

• Behaviours used by organisms to attract a mate

Question 10

Give examples of simple courtship behaviours

Answer 10

• Releasing chemicals - male bees release pheromones
• Sound - male red deer roar
• Visual displays - Great tits puff out their chest

Question 11

Give examples of complex courtship behaviours

Answer 11

• Dancing - blue footed boobies perform a complex dance to show off their blue feet
• Building - bowerbirds make bowers

Question 12

How are courtship behaviours used in classification?

Answer 12

• Are specific to a species
• Are used to prevent interbreeding to produce fertile offspring
• More closely related species have more similar behaviours

Question 13

What is genome sequencing?

Answer 13

• More closely related organisms have more similar DNA sequences - analyse and compare

Question 14

Describe amino acid sequencing

Answer 14

• Amino acids are coded for by DNA sequences
• Related organisms will have similar DNA sequences ad so similar amino acid sequences

Question 15

How do immunological comparisons work?

Answer 15

• Similar proteins will bind to the same antibodies
• E.g. If a human antibody is added to samples from another species - any protein like the human version will also bind to the antibody

Question 16

How does variation occur?

Answer 16

• Genetics - have different genes or alleles
• Environment - e.g. climate, food, lifestyle
• Combination - e.g. genes determine how tall an organism could grow but food availability determines how tall it actually grows

Question 17

Define biodiversity

Answer 17

• Variety of living organisms in an area

Question 18

What are local and global biodiversity?

Answer 18

• Local - a small habitat e.g. garden, meadow, pond
• Global - the variety of species in the world

Question 19

What is a habitat?

Answer 19

• Place an organism lives

Question 20

What is a community?

Answer 20

• All the populations of different species in a habitat

Question 21

Define species richness

Answer 21

• Measure of different species in a community

Question 22

How is agriculture damaging biodiversity?

Answer 22

• Woodland clearance and hedgerow removal - for inc farmland –> removes habitat, shelter, food sources
• Pesticides - kill organisms that feed on crops
• Herbicides - kill weeds –> kill the plants and remove them as a food source
• Monoculture - only farm one type of plant –> supports less organisms

Question 23

How are conservation schemes being used to increase biodiversity?

Answer 23

• Legal protection for endangered species
• Protected areas - prevents further development
• Encourage farmers to plant hedgerows or leave margins around fields for wildflowers to grow