4.3

Question 1

whats classification

Answer 1

the process of sorting living things into groups- helps us understand species biology and identify new species easier

Question 2

what does the system of classification consist of

Answer 2

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

Question 3

whats domain

Answer 3

the highest taxonomic rank which contains 3 groups- the eukaryote, archaea and bacteria

Question 4

whats kingdom

Answer 4

there are 4 eukaryote kingdoms: animalia, plantae, fungi and protoctista and another kingdom, the single celled prokaryota (prokaryotes)

Question 5

whats phylum

Answer 5

all organisms are sorted based on their basic body design; e.g whether they have a backbone

Question 6

whats class

Answer 6

organisms are grouped based on general traits; e.g. number of limbs

Question 7

whats order

Answer 7

a further division based on more specific information e.gg; wolves and cows in the mammalian class (simmilar physiology)

Question 8

whats family

Answer 8

a group of closely related genera e.g; dogs and cats are divided at the family level

Question 9

whats genus

Answer 9

a group of closely related species; e.g the hominid genus containing homo erectus and homo sapiens

Question 10

whats species

Answer 10

the basic unit of classification in this system in which all members show little variation (lions and tigers are diff species)

Question 11

what does binomial naming use

Answer 11

the binomial naming system uses the genus name and species name to avoid confusion when naming species

Question 12

how do u use the binominal naming system irl

Answer 12

write the genus and then the species- if writing using paper underline each word but if typing, use italics

Question 13

why are humans homo sapiens or h. sapiens

Answer 13

because we are the species sapiens or the genus homo

Question 14

when a new species is identified, how is it named

Answer 14

given a scientific name (based on classification) and a common name

Question 15

what are artificial classifications used to group

Answer 15

to group things into convenient groups (e.g all yellow flowers grouped)

Question 16

what are artificial classifications based on

Answer 16

based on few characteristics, do not reflect any evolutionary relationships and provide limited info about species

Question 17

what is the modern classification system based on

Answer 17

based on natural classification of species which uses multiple characteristics and reflects evolutionary relationships

Question 18

whats phylogeny

Answer 18

the study of evolutionary relationships between organisms

Question 19

what are phylogenetic relationships between organisms best depicted with

Answer 19

a phylogenetic tree

Question 20

what do branch tips on the phylogenetic tree represent

Answer 20

represent species at the end of their specific lineage

Question 21

what do branching points on the phylogenetic tree represent

Answer 21

represent common ancestors

Question 22

what do branches on the phylogenetic tree represent

Answer 22

represent evolutionary change/ relatedness

Question 23

what does the direction phylogenetic tree growing represent

Answer 23

corresponds to the time passing

Question 24

why do we classify organisms

Answer 24

• study similar species
• easy to identify life if we classify
• each species has different economic benefits- economic benefit and pure science knowledge
• universal naming allows for better communication
• to study evolutionary relationships> better protection of biodiversity

Question 25

what does the 3 domain system consist of

Answer 25

• eukaryota: contains all the eukaryotes (plants, animals, fungi and different kingdoms of protists)
• bacteria: prokaryotes
• archea: prokaryotes with distinctive metabolisms (extremophiles)

Question 26

why do we have the 3 domain system

Answer 26

to better represent the fundamental cell biology + evolutionary relationships

Question 27

whats classification

Answer 27

the arrangement of organisms into groups of various sizes on the basis of shared features

Question 28

whats taxonomy

Answer 28

a form of classification that focuses on physical similarities between different species, for ease of naming and identification

Question 29

whats convergent evolution

Answer 29

the development of similar features and adaptations through different evoloutionary pathways

Question 30

how is use of biological molecules important in classification

Answer 30

-organisms will have same biological molecules
-cytochrome C is a protein used in respiration, all respiring organisms have cytochrome C.
-but its different in different species
-comparisons abt these differences tell us how closely related we are to other organisms
(slight changes in primary structure)

Question 31

how is use of DNA important in classification

Answer 31

• DNA changes are caused by mutations , these are random and increase with time
• the more changes in DNA, the more mutations have occurred, which means time has passed.
• and more evolution would have taken place, suggesting greater distance in relationship

Question 32

where does mitochondria DNA come from

Answer 32

the mother

Question 33

explain how organisms undergo evolution (6)

Answer 33

1- mutations of DNA sequences produce genetic changes, these cause alternate forms of genes ( alleles) to be produced.
2- this creates genetic diversity between individuals of the same species ( intraspecific variation)
3- resources can be scarce, and there can be selection factors such as predators and disease. Individuals compete for survival.
4- individuals with the characteristics most suited to their environment survive for longer, thus have a greater opportunity to reproduce
5-thus they can pass on their genes for advantageous characteristics
6- the next generation will have more individuals with these characteristics, over time, population can permanently change