B15

Question 1

why did people not believe in the theory of evolution

Answer 1

people thought that God created everything and the Earth was only a couple thousand years old

Question 2

what is Darwins theory of evolution

Answer 2

the theory of evolution by natural selection

Question 3

what observations was Drawins theory based on

Answer 3

• individual organisms in a species showed wide range of variation for a characteristics
• individuals with characteristics which are more suited to the environment are more likely to breed successfuly
• the characteristics which enabled the individulal to survive were passed onto the next generation

Question 4

what did Alfred Russel Wallace do

Answer 4

he also created the theory of evolution by natural selection which caused Drawin to publish his findings in the next year (1859) and Wallace and Darwin also published joint writings in 1858. Afterwards Wallace worked worldwide to find evidence for this theory. He also created the theory of speciation

Question 5

what is speciation

Answer 5

the process in which a new species is formed

Question 6

what was Darwin’s book called

Answer 6

On the Origin of Species

Question 7

why was there a lot of controversy on Darwins’ theory

Answer 7

• there was not a lot of evidence
• it challenged the ides that God created the world and all the species
• the mechanism of natural selection was discovered 50 years later

Question 8

what were other evolutionary theories which conflicted the theory of evolution by natural selection

Answer 8

• the creationist theory
• the theory of intelligent design

Question 9

how does the creationist theory work

Answer 9

that each living thing was created seperately and did not evolve. the time gap in fossils worked as evidence against evolution

Question 10

what is the theory of intelligent design

Answer 10

that complex structures like DNA and mitochondria are far too complicated to have evolved over time and so must have been placed by a higher order of beings

Question 11

what was Lamarck theory of evolution

Answer 11

the theory of inheritance of aquired characteristics and it went like this:
organisms changed throughout their lives because the organism wants too and these changes can be passed on to the next generation and organs which weren’t used will eventually disappear

Question 12

what evidence did Darwin collect which made his theory be accepted in the future

Answer 12

• there is much variation in species
• only the ones which are most adapted will survive
• those who survive will pass on their genes and the rest will become extinct
• more offspring are born thant the environment can handle

Question 13

how has the gene theory evolved

Answer 13

mid 1800s - gregor Mendell - inheritance of characteristics is determined by ‘units’ which are passed on
laste 1800s - chromosomes were observed during cell divison
early 1900s - chromosomes and Mendell’s ‘units’ behaved similarly - idea that genes were located in chromosomes
Mid 1900s - Watson, Crick, Franklin - structure of DNA and gene function was worked out

Question 14

what are some evidence for evolution

Answer 14

• fossils
• study of antibiotic resistance in bacteria

Question 15

how do bacteria become antibiotic resistant

Answer 15

bacteria evolve rapidly as they reproduce at rapid rates. mutations cause new strains in bacteria to be produced. some of these strains are resistant to antibiotics which means they survive and reproduce which means the resistant strain bacteria will spread as people aren’t immune to it and there is no effective cure for it

Question 16

what can we do to reduce the rate of development of antibiotic resitance in bacteria

Answer 16

• doctors shouln’t prescirbe antibiotics for non serious or viral infections
• patients must complete the course of antibiotics so all are killed and none survive to become resistant
• resist the use of antibiotics in agriculture

Question 17

how does speciation occur

Answer 17

1- a population gets isolated forming two groups cretaing 2 different gene pools
2- the 2 populations live in seperate conditions like climarte, food/water availability and new prey/predators
3- natural selection takes place where the most adapted survive and the rest die off. this causes change of characteristics. the longer the 2 populations are seperated the more different they become
4- eventually the 2 groups will become so different that they will no longer be able to breed to produce fertile offspring

Question 18

what are some examples of barriers in speciation

Answer 18

• geographical barriers like seas and mountains
• physical barriers like roads
• behavior barriers like mating calls
• reproduction barriers like different mating times

Question 19

what are some reasons for speciation

Answer 19

• geographical isolation
• ecological isolation
• temperal isolation

Question 20

what are 3 ways fossils can be made

Answer 20

• parts of organisms have not decayed
• conditions for decay are absent
• preserved traces of organisms like footprints

Question 21

how do fossils support Darwins theory of evolution

Answer 21

fossils of the simpler organisms are found in older rocks and more complex organisms are found in the newer rocks which show life forms gradually evolved

Question 22

what is extinction

Answer 22

when there is no living individuals of an organism

Question 23

why might a species become extinct

Answer 23

• new predators
• new diseases
• competition between animals leading to a mutation giving one species an advantage
• environmental change
• catastrophical event
• habitat destruction

Question 24

what is fossil record

Answer 24

the study of the number and placement of fossils in an area

Question 25

why are studying fossils important

Answer 25

• similarities and difference between modern and oldern organisms
• can suggest what a habitat was like
• shows evolution over time

Question 26

how has the horse evolved

Answer 26

1- 4 toed to run on soft ground
2- lost 1 toe for moving faster on dry ground
3- middle toe turned to hoof to run faster
4- other toes lost as only hoof is only used
5- single hoof bigger to run on hard ground

Question 27

what is classification

Answer 27

the organisation of living organisms into groups according to their similarities

Question 28

why is classification important

Answer 28

• it helps to understand how different groups of organisms are related to each other
• it helps us to recognise biodiversity in the world
• gives scientists a common language to talk in

Question 29

what are the 7 taxons/classes

Answer 29

Kingdom, Phylum, Class, Order, Family, Genus, Species

Question 30

what did Linnaeus come up with

Answer 30

the binomial system where an organisms’ scientific name is based on its’ genus and species name e.g panthera leo = lion

Question 31

what is a Mnemonic to help remember the taxons

Answer 31

King
Penguins
Climb
Over
Frozen
Grassy
Slopes

Question 32

what are the 5 kingdoms

Answer 32

• fungi
• animalia
• plantae
• prokaryote
• protoctists

Question 33

what did Carl Woese do?

Answer 33

discovered a new category of organisms called anarchae which were similar to bacteria but different as they lacked some RNA sequences which were core characteristics of bacteria

Question 34

how did Woese class the organisms

Answer 34

he did it by having 3 main divisions:
- anarchaea
- prokaryota
- eucarya