classification

Question 1

classification definition

Answer 1

arranging organisms into groups based on their similarities and differences

Question 2

what is taxonomy

Answer 2

the study of classification

Question 3

what are the taxonomic groups

Answer 3

kingdom
phylum
class
order
family
genus
species

Question 4

who were the hierarchial classification systems proposed by

Answer 4

Carl Linneaus (18th century)

Question 5

what additional level of classification has now been added

Answer 5

domain

Question 6

why do scientists classify organisms

Answer 6

• to identify species
• to predict characteristics
• to find evolutionary links

Question 7

what nomenclature (naming system) is used for classification

Answer 7

• binomial system
• in Latin
• proposed by Carl Linneaus
• genus with capital letter (generic name)
• species name in lowercase (specific name)
• written in italics or underlined

Question 8

definition of species

Answer 8

group of organisms that are able to reproduce to produce fertile offspring

Question 9

why are mules infertile

Answer 9

their cells contain an odd number of chromosomes (63)

Question 10

binomial name for humans

Answer 10

Homo sapiens

Question 11

who classified organisms into 2 kingdoms (plants and animals)

Answer 11

Aristotle

Question 12

when did scientists start classifying organisms into 5 kingdoms and who did it

Answer 12

1960s
Robert Whittaker, based on Carl Linneaus’ principles

Question 13

what are the 5 kingdoms

Answer 13

• prokaryotae
• protoctista
• fungi
• plantae
• animalia

Question 14

prokaryotae features

Answer 14

e.g. bacteria
- unicellular
- less than 5 micrometers
- no nucleus or membrane bound organelles
- small ribosomes (70s)
- no visible feeding mechanism (nutrients absorbed through cell wall or produced by photosynthesis)

Question 15

protoctista

Answer 15

e.g. algae, protoza
- unicellular (mainly)
- nucleus and membrane bound organelles
- some have chloroplasts
- some are immobile, but others move by flagella, cilia
- nutrients are acquired by photosynthesis (autotrophic) and ingestion of other organisms (heterotrophic), some parasitic

Question 16

fungi

Answer 16

• unicellular/multicellular
• nucleus and membrane bound organelles
• chitin cell wall
• no chloroplasts
• immobile
• most have body made of threads/hyphae
• nutrients acquired by absorption (decaying material)(saprophytic), some parasitic
• most store food as glycogen

Question 17

plantae

Answer 17

• multicellular
• nucleus and membrane bound organelles
• chloroplasts
• cellulose cell wall
• immobile
• nutrients acquired through photosynthesis (autotrophic)
• store food as starch

Question 18

animalia

Answer 18

• multicellular
• nucleus and membrane bound organelles
• no chloroplasts
• move with aid of cilia, flagella, proteins, muscular organs
• nutrients acquired by ingestion (heterotrophic)
• food stored as glycogen

Question 19

phylogeny

Answer 19

evolutionary relationships/history between organisms

Question 20

phylogenetics

Answer 20

the study of the evolutionary history of groups of organisms
- reveals which group an organism is related to and how closely related they are

Question 21

advantages of phylogenetic classification as opposed to Linnaean classification

Answer 21

• phylogeny can be done without reference to Linnaean classification
• phylogeny produces a continuous tree whilst classification requires discrete groups
• the hierarchal nature of Linnaean classification can be misleading as it implies different groups within the same rank are equivalent. e.g. cats and orchids are both a family, but one has been around for 30 million years compared to 100 million