Classification & Evolution

Question 1

what is classification

Answer 1

devising a specific grouping process and assigning different organisms to groups

Question 2

why is it essential to use molecules (DNA or cytochrome c) as evidence

Answer 2

no identical in all species so when comparing sequences of amino acids in samples, similarities and differences can be identified to classify

Question 3

phylogeny

Answer 3

the study of the evolutionary relationships between species which involves studying how closely related different species are

Question 4

the more recent the common ancestor…

Answer 4

the more closely related the 2 species

Question 5

taxonomy

Answer 5

the study of the organisation of organisms (taxa) into hierarchies, which attempt to take into account their supposed evolutionary descent

Question 6

taxon

Answer 6

a group of organisms that share common features

Question 7

species

Answer 7

a group of individuals with a large number of features in common, can interbreed and produce fertile offspring

Question 8

why is Latin not English

Answer 8

it is a universal scientific language

Question 9

common ancestor

Answer 9

the most recent individual from which a set of organisms in 2 or more different groups are directly descended

Question 10

natural selection

Answer 10

a process of evolution by selecting individuals with certain adaptations to survive and reproduce, which are passed on to the next generation, over time more and more individuals will have the adaptive characteristics so has been ‘selected’

Question 11

development of identical twins

Answer 11

start as 1 cell that divides and separates into 2 cells which form 2 separate people- 2 original cells have same genetic information but DNA replication /cell division introduces changes to DNA. also environ. difference in womb/after birth

Question 12

intraspecific variation

Answer 12

variation within species- different characteristics between diff people
greater the genetic diversity of a species, greater the intraspecific variation

Question 13

interspecific variation

Answer 13

variation between species- characteristics used to separate members of 1 species from another

Question 14

continuous variation

Answer 14

there are 2 extremes and a full range of intermediate values between them, often regulated by more than one gene and influenced by environ (e.g. height)

Question 15

discontinuous variation

Answer 15

2 or more extinct value categories with no intermediate values, members of species may be evenly distributed between diff forms/more of one type, regulated by single gene and not influenced by environ. (e.g. gender)

Question 16

inherited/genetic variation

Answer 16

unique combination of alleles inherited from our parents defines our characteristics, we share alleles with other members of our species/other species but never complete match

Question 17

environmental variation

Answer 17

characteristics are affected by the environment e.g. skin will tan/go darker with exposure to sunlight

Question 18

combined effects as a cause of variation

Answer 18

environmental and genetic variation are not isolated, not all our genes are active at any 1 time and changes in the environ. can also directly affect which genes are active e.g. humans now taller due to better diet but also depend on genes

Question 19

role of adaptations

Answer 19

help the organism to cope with environmental stresses and obtain the things they need to survive

Question 20

a well-adapted organism will be able to….

Answer 20

find enough food/water/photosynthesise well, get enough nutrients, defend from predators/diseases, survive physical conditions of its environ, respond to changes in environ, sufficient energy for successful reproduction

Question 21

convergent evolution

Answer 21

when 2 unrelated species living in a similar habitat evolve similar adaptations e.g. marsupial and placental moles both have short fur