Classification And Biodiversity

Question 1

Definition of phylogenetic

Answer 1

Reflecting evolutionary relatedness

Question 2

Phylogenetic method

Answer 2

Grouping closely related organisms together- may show physical similarities.

Question 3

Phylogenetic tree

Answer 3

• diagram showing evolutionary descent
• living organisms at tips of branches
• ancestral species in the branches and trunk
• branch points representing common ancestors

Question 4

Definition of hierarchy

Answer 4

Smaller groups are components of larger ones

Question 5

Definition of Taxon

Answer 5

Group with system of classification

Question 6

What is meant by taxa are discrete?

Answer 6

An organism belongs in only one Taxon

Question 7

What is the hierarchy of biological classification?

Answer 7

Domain
Kingdom 
Phylum 
Class
Order
Family 
Genus 
Species

Question 8

Reasons for classifying

Answer 8

• infer evolutionary relationships
• predict characteristics when a new animal is discovered
• easier to say
• more useful to count families than species when describing the health of an ecosystem or rate of extinction

Question 9

What are the three domains?

Answer 9

• Eubacteria: prokaryotes ( e.coli and salmonella)
• Archaea: bacteria, unusual metabolism, live in marginal habitats, prokaryotes
• Eukaryota: plantae, animalia, fungi, protoctista

Question 10

Definition of genus

Answer 10

A group of similar organisms

Question 11

Definition of species

Answer 11

A group of organisms sharing a lot of physical features and able to interbreed to make fertile offspring

Question 12

Definition of prokaryota

Answer 12

Microscopic

All bacteria and Cyanobacteria

Question 13

Definition of protoctista

Answer 13

• some have one cell, major component of plankton
• some are colonial
• spirogyra- plant like cells
• amoeba- animal like cells
• euglena- characteristics of both plant and animal cells
• some have many similar cells- seaweeds or algae

Question 14

Definition of plantae

Answer 14

• mosses, horsetails and ferns reproduce with spores

- conifers and flowering plant, which reproduce with seeds

Question 15

Definition of fungi

Answer 15

Yeasts- single called

Mounds- hyphae weave together to form mycelium

Question 16

Definition of animalia

Answer 16

35 animal phyla

Most are motile at some stage

Question 17

Definition of homologous structure

Answer 17

Similar form and developmental origin but different functions.

Question 18

Definition of divergent evolution

Answer 18

Common ancestral structure has evolved and performs different functions

Question 19

Definition of convergent evolution

Answer 19

Structures evolve similar properties but have different developmental origins

Question 20

Definition of analogous structure

Answer 20

Corresponding function and similar shape but different developmental origin

Question 21

What are the 4 ways of assessing relatedness with genetic evidence?

Answer 21

• DNA sequences
• DNA hybridisation
• amino acid sequences
• immunology

Question 22

Morphological definition of species

Answer 22

If two organisms look very similar they are likely to be in the same species
Sexual dimorphism must be taken into account- presence of manes in male lions but in females

Question 23

Reproductive definition of species

Answer 23

Two organisms in the same species can interbreed to make fertile offspring
Dissimilar organisms may have different chromosomes no or incompatible physiological

Question 24

Definition of binomial system

Answer 24

The system of giving organisms a unique name with two parts, the genus and species.

Question 25

Definition of taxonomy

Answer 25

Identification and naming of organisms

Question 26

What does taxonomy allow us to do?

Answer 26

- discover and describe biological diversity - investigate evolutionary relationships - classify organisms to reflect evolutionary relationships

Question 27

Advantages of binomial system

Answer 27

- unambiguous naming - used all over the world - implies species sharing a name are closely related

Question 28

Definition of biodiversity

Answer 28

The number of species and the number of each species in a specified region

Question 29

Definition of biodiversity hotspots

Answer 29

Major areas of biodiversity | Around the equator and tropics

Question 30

Impacts of reduced biodiversity

Answer 30

- plant species provide staple foods e.g. Wheat and rice - medicinal drugs from plants and fungi - living organism provide important raw materials e.g. Rubber cotton - each species is unique

Question 31

Definition of natural selection

Answer 31

The gradual process in which inherited characteristics become more or less common in a population, in response to the environmental determining the breeding success of the individuals possessing those characteristics

Question 32

Definition of adaptation

Answer 32

The change in a species as a useful characteristic becomes more common

Question 33

Examples of anatomical traits

Answer 33

Stream lined body | Honey guides indicate centre of flower

Question 34

Examples of physiological traits

Answer 34

Polar bear- body temp drops to 2 degrees to use less energy | Leaves fall of trees so water is not lost in transpiration

Question 35

Examples of behavioural traits

Answer 35

Plants flower in spring when pollinating insects have emerged Mating rituals- peacocks

Question 36

Definition of selection pressures

Answer 36

Environmental factors that affect an individual's reproductive success