Classification processes

Question 1

Advantages of Classification

Answer 1

• makes communication about living things much easier and more efficient
• allows easier analysis of the relationships between species

Question 2

Hierachial classification

Answer 2

• domain
• kingdom
• phylum
• class
• order
• family
• genus
• species

Question 3

Linnaeus naming system

Answer 3

Based on physical features:
Two epithets
- generic epithet
unique to that genus
- specific epithet
not necessarily unique as other species in different genera may have same specific epithet

Question 4

Different types of Kingdoms

Answer 4

• animals
• plants
• fungi
• protists
• archaea
• bacteria

Question 5

The 3 domains

Answer 5

• bacteria
• archaea
• eukarya

Question 6

Dichotomous keys

Answer 6

Allow the identification of a species by dividing all possible species in two, etc, based on observable traits

Question 7

Asexual reproduction

Answer 7

Advantages:
- does not require special cells or a lot of energy
- can produce offspring quickly
- in a stable environment creates large, thriving population

Disadvantages:
- limited ability to adapt
- faces massive die-off if environment changes

Question 8

Sexual Reproduction - R

Answer 8

R-strategist
- r = growth rate
- high r value and low carrying capacity
- grows fast but most die due to density independent factors - climatic events, fires

Question 9

Sexual reproduction - K

Answer 9

K-strategist
- low r and high K
- grows logarithmically - slow but more survive
- threats are density dependent factors - predation, competition

Question 10

Advantages/Disadvantages of K

Answer 10

Ad:
- lots of variation within a species
- able to live in a variety of environment
- able to adapt to changes in the environment

Dis:
- needs time and energy
- produces small populations

Question 11

What are the 4 types of species interactions?

Species Interactions

Answer 11

• predation
• competition
• symbiosis
• disease

Question 12

What is predation

Answer 12

• any interaction between 2 organisms where the predator consumes another organism

Question 13

What is competition?

Answer 13

• where both organisms are harmed
• when individuals compete for space/resources/mates etc.
• interspecific - competition between different species
• intraspecific - competition in the same species

Question 14

What is symbiosis?

Answer 14

Mutualism:
- both species benefit
- anemome protects clownfish / clownfish provides faecal matter for food

Commensalism:
- one benefits / other is unaffected
- barnacles transported to plankton-rich waters by whales

Amensalism:
- one is destroyed/ other is unaffected
- fungi secreting penecillin

Parasitism:
- one benefits/ other is harmed
- ticks/fleas feed on the blood of canine host

Question 15

What is disease?

Answer 15

Organisms can be classified based on their role in a disease

Parasite:
- organism which lives/feeds of host and causes harm

Pathogen:
- biological agent that causes disease or illness

Host:
- organism that harbours a parastic, mutualistic or commensalist guest

Vector:
- organism that spread infection by spreading pathogens from one host to another

Question 16

What is phylogeny

Answer 16

• the study of relationships among different groups of organisms and their evolutionary development

Question 17

What are cladisitics?

Answer 17

• where organisms are categorised in groups based on the most common ancestor

Question 18

How can you tell the relatedness of two organisms through amino acids?

Answer 18

• you can compare the DNA sequences between the two organisms by looking for the similarities between bases

Question 19

How do molecular clocks work

Answer 19

• the number of nucleotide substitutions in related genes is proprotional to the time since they last shared a common ancestor
• as species diverge, there will be a difference in the amino acid sequence due to accumulation of mutations

Question 20

What is a phylogenetic tree?

Answer 20

• they represent evolutionary relationships among organisms

Question 21

Define the term clade:

Answer 21

• a group of organisms that consists of a common ancestor and all its lineal discendants

Question 22

what are the three common assumptions of cladistics?

Answer 22

1. Any group of organisms are related by descenet from a common ancestor
2. There is a branching pattern of lineage-splitting
3. Change in physical characteristics occurs in lineages over time

Question 23

Why is there a need for multiple definitions of species?

Answer 23

Multiple definitions are required because some specific defitions cannot be applied to organisms that do not reproduce sexually.

• morphological
• biological
• ecological
• genetic
• phylogenetic

Question 24

What are the definitions of morphological and biological species

Answer 24

Morphological:
- differentiate species through differences in form and structure of organisms

Biological:
- a group of similar organisms that are capable of sexually interbreeding to produce fertile offspring

Question 25

What defintions of ecological and ecological niches

Answer 25

Ecological:
- defines a species by the resources that the particular group of organsims uses and depends on the specialised ecological niche the group occupies

Niche:
- the role the species plays in an environment
- includes habitat, food, location of reprouction and relationships with other species

Question 26

What are the definitions of genetic and phylogenetic species

Answer 26

Genetic:
- utilises both inherited genetic traits of an organism plus the amount of genetic variation in a population

Phylogenetic:
- an introducible group whose members are descended from a common ancestor
- all possess a combination of certain defining or deriving traits