Evolution, Fossils, Speciation + Classification (paper 2)

Question 1

Evolution definition

Answer 1

gradual change in the
inherited characteristics of a population over a long period of time through a process of natural selection which may result in the formation of a new species

Question 2

what does the theory of evolution by natural selection state

Answer 2

that all species of
living things have evolved from simple life forms that first developed more than three billion years ago

Question 3

how does evolution arise

Answer 3

through natural
selection of variants that give rise to phenotypes best suited to their environment

Question 4

how do you know when 2 populations of 1 species has formed into 2 new species

Answer 4

so different in phenotype that they can no longer interbreed to produce fertile offspring

Question 5

what are the key ideas for the theory of evolution by natural selection

Answer 5

• individual organisms within a particular species who a wide range of variations for a characteristics –> mutations can also give rise to new variants
• individuals with characterics most suited to the environment are more likely to survive to breed successfully**
• that characteristics that have enable these individuals to survive are them passed onto the next generation –> advantageous alleles passes into offspring during reproduction

Question 6

describe the process of evolution by natural selection

Answer 6

1. genetic variation caused by mutations in the species
2. those with the desirable characteristics survive + reproduce = survival of the fittest
3. the allele that codes for tha characteristics gets passed down to offspring
   over many generations, those with the desirable alleles increase and outcompete those without

Question 7

the theory of evolution by natural selection was only gradually accepted because:

Answer 7

• the theory challenged the idea the God make all animals and plant that live on Earth
• Insufficient evidence at the time the theory was published to convince many scientists
• the mechanism of inheritance / genetics and variation was not know until 50 years after the theory was published

Question 8

who else had a theory

Answer 8

Jean-Baptiste Lamarck

Question 9

what was Lamarck’s theory

Answer 9

theory that changes that occur in a organism *during its lifetime** can be inherited

Question 10

speciation =

Answer 10

when 2 new species form from an ancestral species

Question 11

Wallace independently proposed which theory

Answer 11

the theory of evolution by natural selection

Question 12

what is Wallace best know for

Answer 12

• work in warning colouration
• theory of speciation

Question 13

describe the stages which give rise to new species

Answer 13

1. genetic variation exists within a species / or random mutations leads to new variants
2. population of a species become geographically isolated from each other (geographical barrier)
3. the separate population are exposed to different environmental conditions
4. natural selection occurs differently in both populations
5. this occurs over many generations
6. if two population reunite, no longer able to interbreed to produce fertile offspring - have become different species

Question 14

bacteria can ………… …………… because they ………….. at a ……… ……….

Answer 14

evolve rapidly
reproduce
fast rate

Question 15

how does antibiotics bacteria occue

Answer 15

• in all population there is variation
• mutations also occur naturally + spontaneously
• mutations occur in pathogenic bacteria
• this produces new strains of bacteria
• some strains might be resistant to antibiotics

Question 16

how do antibiotic resistance bacteria survive and spread

Answer 16

• when a person takes a *specific antibiotic** it will kill specific bacteria
• however some bacteria develop random mutations in their DNA –> occasionally they become anti-biotic resistant and are not killed
• anti-biotic resistant bacteria 8*survive + rapidly reproduce**
• these is less competition for nutrients and resources since antibiotic have killed non-resistant bacteria
• anti-biotic resistant bacteria population rises = anti-biotic resistant strain
• anti-biotic resistant bacteria can then be spread to uninfected people - a communicable pathogen
• will spread further as there is no effetive treatment

Question 17

what is the name of a common strain of anti-biotic resistant bacteria

Answer 17

MRSA - Methicillin - Resistant Staphylococcus Aureus

Question 18

to reduce the rate of development of antibiotic resistant strains: (3 ways):

Answer 18

• doctors should not prescribe antibiotics inappropriately -
  treating non-serious or viral infections
• patients should complete(( their full course of antibiotics so all bacteria are killed and ((none survive to mutate and form resistant strains
• the agricultural use of antibiotics should be restricted

Question 19

why is the development of new antibiotics hard

Answer 19

• costly
• slow
• unlikely to keep up with the emergence of new resistant strains

Question 20

Fossils are …

Answer 20

are the ‘remains’ of organisms from millions of years ago, which are found in rocks

Question 21

what are the 3 ways in which a fossils can be formed:

Answer 21

• from parts of organims that have not decayed because one or more of the condition needed for decay are absent:
  
  • warmth moisture, oxygen, missing
  • ice, amber
  • bacteria unable to decompose
• when parts are replaced by minerals as they decay
• as preserved traces of organisms - footprints, burrows, rootlet traces

Question 22

why are fossil records incomplete

Answer 22

• many early life forms were soft-bodied - only left a few traces behind
• most traces would have been destroyed by geological activity
• most organisms just fully decay - no not fossilise

Question 23

extinction =

Answer 23

when no remaining individuals of a species is still alive

Question 24

extinction may be caused by : (6 reasons)

Answer 24

• changes to the environment over geological time
• new predators
• new diseases
• increased competition - new competitors
• a single catastrophic event

Question 25

how are living things traditionally classified

Answer 25

into groups depending on **structure** and **characteristics**

Question 26

what are the 2 types of classification

Answer 26

- Linnaean system - three domain system

Question 27

who invented the Linnaean system

Answer 27

Carl Linnaeus

Question 28

Linnaeus classified living things into:

Answer 28

kingdom, phylum, class, order, family, genus, species

Question 29

how are organisms named

Answer 29

by the binomial system of **genus and species**

Question 30

due to what where new models of classification propsed

Answer 30

- evidence of **internal structures** became more developed due to improvement in **microscopes** - understanding of **biochemical processes progressed**

Question 31

who invented the 3 domain system and how

Answer 31

**Carl Woese** - due to evidence available from **chemical analysis**

Question 32

what is the 3 domain system divided into

Answer 32

**Archaea** - primitive bacteria usually living in extreme environments - **Bacteria** - true bacteria - **Eukaryotes** - protists, fungi, plants, animals

Question 33

what is the anacronym for the Linnaeus system

Answer 33

Dear Katie Please Come Over For Great Snacks

Question 34

how must the species name be written if hand written

Answer 34

- **capital** letter for **Genus** - **lower case** for **species** - both **underlined**

Question 35

what doe evolutionary trees show

Answer 35

- common ancestors - relationships between species