5.3 Classification of Biodiversity

Question 1

what is the bionomila nomenclature system

Answer 1

invented by carl linneaus in the 19th century

it was developed because organisms have different names in different countries so you want to avoid confusion over which animal is being discussed.

it gets updates at congresses regularly where scientists agree upon the naming of new sepcies

Question 2

what are teh rules of the binomial nomenclature system

Answer 2

2 words m- genus and speceis

1. genus in capital species lower case
2. when printed the name is in italics
3. it can be abbreviated to genus name intial letter adn full species name
4. the internationally agreed bame is teh name that was first published from teh 1750s onwards

Question 3

what is the current hierarchy of the taxxa and how has it changed

Answer 3

1. domain
2. kindgom
3. phylus
4. class
5. order
6. family
7. genus
8. species

domain was added due to evidence from genetic studies

Question 4

waht are domains

Answer 4

originally eurkaryote and prokaryotes

then synthesis showed that the ribosomal RNA, cell walls and cell membranes of prokaryotes are very different so two new groups were created bacteria adn archae

archae live in extreme habitats - boilign hot, lots of salt

e.g. methanogens in cows stomachs live in very anaerobic environement

Question 5

what about viruses

Answer 5

they do not have enough characteristics of life to be living.

htey are not classified into a domain even though they use the same gentic code

Question 6

what are the different kingdoms in the eukaryote domain and why are they controversial?

Answer 6

plant, animal fungi, protoctista

• protoctista arguably should be made into several seperate kingdoms as there is lots of variety

Question 7

what is natural and artifical classification

Answer 7

natural - classifies species together based on how they have evolved so species of the same genus share a common ancestor and therefore similar characteristics.

this is diffficult as covergent evolution can give rise to analogous structures and adaptive radiation can make closely related organisms seem very different

artifical - classfiies species based on similar characteristics regardless of evolution - species grouped together that have no common ancestor

e.g. bird and bats grouped togetehr as have analogous structrues due to convergent evolution but actually have different genetic origins and are only superficially similar

Question 8

how has classification changes recently

Answer 8

recent genetic evidence shows that 2 organisms do / do not have a common ancestor so we need to change

• teh taxon (group)

merge two taxons

split a taxon

e.g. jhuman were originally asigned primate order and hominidae family and the great apes were in the pongidae family

but recent genetic evidence shows that chimpanzees and gorillas are closer related to humans so should ne in teh same family. jsut oranguatans in the pongidae family.

also gorillas are closer to us than chimpanzees so should be a seperate genus from chimpanzees

Question 9

what are the advantages of natural classfication

Answer 9

1. we can easily identify what species an organism is - you can look at its characteristics and assign it first to its kingdom andthen down to species - use of the dichotomous keys to help wiht this - artifical classification can make this difficult as e.g. if flowering plants are classed basedon flower colour - all white flowers are grouped together how would classifie white flowered bluebells? if it normally has blue flowers
2. we can predict the characteristics of species whithin a group as tehy all have similar characteristics due to similar genetic origins- if bats were classified artifically they would be with flying organisms not related to them so we could not make predictions

Question 10

what are the plant phyla + examples

Answer 10

1. bryophyta - mosses
2. filicinophyta - ferns
3. coniferophyta - conifers
4. angiospermophyta - flowering plants

Question 11

what are the animal invertebrate phyla (30 but name 6)

Answer 11

1. porifera -sea sponges
2. cnidaria - jellyfish
3. platyhelminthes - tapeworms
4. mollusca - snails
5. annelida - earthworms
6. arthropods - insects, scorpions

Question 12

the chordate (vertebrate) phylum of animals - classes

Answer 12

1. bony ray finned fish - zebra fish
2. amphibians - frogs
3. reptiles - lizards
4. birds - sparrows
5. mammals - elephants