Biodiversity and classification

Question 1

Classification

Answer 1

The process of naming and organising organisms into a group based on their characteristics and evolutionary history.

Question 2

Can the classification of an organism change?

Answer 2

The classification of an organism may change as new info becomes available.

Question 3

Name the hierarchy of taxons in order from largest to smallest.

Answer 3

Kingdom, phylum, class, order, family, genus, species.

Question 4

Name the 5 kingdoms.

Answer 4

Animalia, fungi, plantae, prokaryotes and protocista.

Question 5

What is the three domain classification system?

Answer 5

A method of classification in which organisms are categorised into three groups; Archaea, Bacteria and Eukarya.

Question 6

How was the three domain classification system developed?

Answer 6

Was developed by analysing molecular differences between organisms to determine their evolutionary relationships. Evidence showed that the kingdom ‘prokaryotae’ could be divided into two groups and all other organisms are eukaryotes.

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

Bacteria

Answer 8

One of the three domains and consists of ‘true’ bacteria.

Question 9

Archaea

Answer 9

One of the three domains, made up of primitive bacteria existing in extreme environments.

Question 10

Eukarya

Answer 10

One of the three domains and consists of all eukaryotic organisms.

Question 11

Features of the kingdom Prokaryotae

Answer 11

• Unicellular prokaryotes
• Lack of a true nucleus and membrane-bound organelles.
• Rigid cell wall.

Question 12

Features of the kingdom Plantae

Answer 12

• Multicellular eukaryotes
• Photoautotrophs
• Cellulose cell walls

Question 13

Features of the kingdom Animalia

Answer 13

• Multicellular eukaryotes
• No cell wall
• Heterotrophic
• Nervous coordination

Question 14

Features of the kingdom Fungi

Answer 14

• Eukaryotes
• Heterotrophic
• Chitin cell walls
• Grow by producing branching filaments called hyphae
• Asexual reproduction via spores

Question 15

Features of the kingdom protoctista

Answer 15

• Mainly unicellular eukaryotes

- No differentiation into tissues

Question 16

Different types of evidence used in classification:

Answer 16

• Observations (organisms grouped based on similar physical characteristics).
• Biochemical methods.

Question 17

DNA profiling

Answer 17

A method of determining the characteristics of an individual’s DNA - percentage of DNA or proteins shared between species is used to estimate relatedness.

Question 18

The advantage of using biochemical methods of classification.

Answer 18

Reduce mistakes made from observing physical features alone (due to morphological convergence).

Question 19

Homologous features

Answer 19

Have evolved from the same structure for different functions. They indicate a common ancestor.

Question 20

Analogous features

Answer 20

Structures that have evolved independently for the same functions.

Question 21

Species

Answer 21

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

Question 22

What are the two components to a binomial name?

Answer 22

The genus and the species.

Question 23

What is the advantage of binomial naming?

Answer 23

The binomial system is universal.

Question 24

Biodiversity

Answer 24

The number of species and the number of individuals if each species in a specified geographic region.

Question 25

What mechanism has generated biodiversity?

Answer 25

Natural selection.

Question 26

When measuring the biodiversity of a habitat, what must ecologists consider?

Answer 26

Species richness (the number of different species found within an area) and species evenness (the number of individuals of each species living together in a community.

Question 27

How can biodiversity in a habitat be assessed?

Answer 27

Simpson's Diversity index.

Question 28

What is Simpson's Diversity index?

Answer 28

- A value between 0 and 1 found (the greater the value the greater the biodiversity). - It considers both species evenness and richness.

Question 29

Polymorphism

Answer 29

The presence of different phenotypes among members of a single species.

Question 30

How can biodiversity be assessed at the molecular level?

Answer 30

Using DNA fingerprinting and sequencing.

Question 31

DNA sequencing

Answer 31

Determining the entire DNA nucleotide base sequence of an organism.

Question 32

How can DNA sequencing used to measure biodiversity?

Answer 32

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

Question 33

Adaptation

Answer 33

A feature of an organism that increases its chances of survival in its environment.

Question 34

Types of adaptations:

Answer 34

- Anatomical (changes to physical features). - Physiological (changes to bodily processes). - Behavioural (changes to actions).