Unit 2 (2.1)

Question 1

Classification definition

Answer 1

Classification is the division of living organisms into groups based on their evolutionary relationships.

Question 2

Species definition

Answer 2

A group of similar organisms that can interbreed to produce fertile offspring

Question 3

Can the classification of an organism change?

Answer 3

Yes, as new information becomes available

Question 4

Seven groups in hierarchy

Answer 4

Kingdom
Phylum
Class
Order
Genus
Species

Question 5

Five kingdom classification system

Answer 5

Animal
Fungi
Plantae
Prokaryote
Protoctista

Question 6

Three domain classification system

Answer 6

Archaea
Bacteria
Eukarya

Question 7

What do organisms in the same domain have in common?

Answer 7

Organisms in the same domain share a distinctive pattern of ribosomal RNA

Question 8

Animalia characteristics

Answer 8

Multicellular eukaryotes
No cell wall
Heterotrophic
Nervous coordination

Question 9

Prokaryotae characteristics

Answer 9

Lack of nucleus
Lack of membrane bound organelles
70s ribosomes
Circular DNA
Peptidoglycan cell wall

Question 10

Protoctista characteristics

Answer 10

Mostly unicellular eukaryotes
Algae have no tissue differentiation

Question 11

Plantae characteristics

Answer 11

Multicellular eukaryotes
Photosynthetic containing chloroplasts
Cellulose cell wall

Question 12

Fungi characteristics

Answer 12

Heterotrophic eukaryotes
Cell wall made of chitin
Most composed of thin threads of hyphae
Reproduce by spores

Question 13

How to find out the relatedness of organism

Answer 13

Physical features
Biochemical methods

Question 14

Physical features and biochemical methods

Answer 14

DNA ‘genetic fingerprinting’
Enzyme studies

Question 15

What is DNA profiling

Answer 15

Method of determining the characteristics of an individuals DNA

Percentage of DNA or proteins shared between species is used to estimate relatedness

Question 16

Use of binomial system in naming system

Answer 16

In the binomial system of classification, each organism is named for its genus then its species.

Question 17

Advantage of binomial system

Answer 17

Biochemical methods reduce mistakes made from observing physical features alone.

It’s universal

Question 18

What are the two components to a binomial

Answer 18

Generic name (genus) must be capitalised
Specific name (species)

Question 19

What is a homologous feature?

Answer 19

Homologous features have evolved from the same structure for different functions. They indicate a common ancestor

Question 20

What is a Analogous feature?

Answer 20

Analogous features are structures that have evolved independently for the same function.

Question 21

Homologous feature example

Answer 21

Pentadactyl limb found in mammals, birds and reptiles

Question 22

Analogous feature example

Answer 22

The wings of birds and insects

Question 23

What is biodiversity?

Answer 23

The number and variety of living organisms in a given region. It is affected by environmental, genetic and human factors.

Question 24

What factors can biodiversity be affected by?

Answer 24

Environmental factors
Genetic factors
Human factors

Question 25

How can biodiversity in a habitat be assessed?

Answer 25

Using Simpson's Diversity index

Question 26

What is Simpson's Diversity index?

Answer 26

A measurement of diversity that considers both species richness and evenness A value between 0 and 1 is found The closer the value is to 1, the greater the biodiversity

Question 27

How can biodiversity can be assessed within a species at a genetic level?

Answer 27

By looking at the variety of alleles in the gene pool of a population, e.g. the proportion of polymorphic loci across the genome.

Question 28

How can we calculate genetic diversity within a species?

Answer 28

Proportion of polymorphic gene loci= Number of polymorphic gene loci ------------------------------- Total number of loci

Question 29

What is polymorphism?

Answer 29

The presence of different phenotypes among members of a single species

Question 30

How can biodiversity be assessed at a molecular level?

Answer 30

Determining the entire DNA nucleotide base sequence of an organism

Question 31

How is DNA sequencing used to measure biodiversity?

Answer 31

Comparisons between members of the same species can identify variation in base sequences and hence estimate genetic diversity.

Question 32

How has biodiversity been generated?

Answer 32

Through natural selection

Question 33

What is an adaptation?

Answer 33

A feature of an organism that increases its chance of survival in it's environment

Question 34

What are the three types of adaptation?

Answer 34

Anatomical- Changes to physical features Physiological- Changes to bodily processes Behavioural- Changes to actions