A4.1

Question 1

What is evolution

Answer 1

Evolution is defined as the process of cumulative change in the heritable characteristics of a population

Question 2

what is cumulative change

Answer 2

a gradual accumulation of small changes

Question 3

what are heritable characteristic

Answer 3

features which can be inherited (caused by genes, passing from one generation to the next, so it takes a long time to happen) (think about life span of different organisms; life span of bacteria vs cats and dogs vs human beings)

Question 4

level of organisation

Answer 4

species –> population –> community –> ecosystem –> biome –> biosphere

Question 5

what is species (Not define)

Answer 5

Species is the basic unit of classification and a taxonomic rank

Question 6

define species

Answer 6

A species is a group of organisms that can potentially interbreed to produce fertile, viable offspring

Question 7

what are fertile offsprings

Answer 7

Those which can in turn interbreed and pass on their genes to another generation.

Question 8

define population

Answer 8

A population is a group of organisms of the same species that are living in the same area at the same time

Question 9

define community

Answer 9

A group of populations living together and interacting with each other within a given area

Question 10

define habitat

Answer 10

The environment in which a species normally lives, or the location of a living organism

Question 11

define ecosystem

Answer 11

A community and its abiotic environment (i.e. habitat)

Question 12

what are abiotic factors

Answer 12

Non-living factors, such as pH, salinity, wind speed, type of soil, etc.

Question 13

what are biotic factors

Answer 13

Living factors in an ecosystem, such as the plants and animals.

Question 14

define biome

Answer 14

A collection of ecosystems sharing similar climatic conditions

Question 15

define biosphere

Answer 15

That part of the Earth inhabited by organisms

Question 16

can members from one species reproduce with another species?

Answer 16

Members of a single species are unable to produce fertile, viable offspring with members from a different species

Question 17

What happens when two different species interbreed?

Answer 17

When two different species do produce offspring by cross-breeding, these hybrids are reproductively sterile (e.g. liger, mule)

Question 18

What is ecology?

Answer 18

The study of the relationship between living organisms, or between living organisms and their environment

Question 19

What are the 3 ways organisms can obtain chemical energy?

Answer 19

autotrophs
heterotrophs
mixotrophs

Question 20

biochemical evidence for evolution

Answer 20

Evidence for evolution from base sequence in DNA or RNA and amino acid sequences in proteins

Question 21

sequence data

Answer 21

Sequence data gives powerful evidence of common ancestry

Question 22

selective breeding for evolution

Answer 22

Evidence for evolution from selective breeding of domestic animals and crop plants

Question 23

how is selective breeding an evidence for evolution

Answer 23

Variation between different domesticated animal breeds and varieties of crop plant, and between them and the original wild species, shows how rapidly evolutionary changes can occur

Question 24

what is artificial selection

Answer 24

Farmers and breeders choose desirable genetic characteristics to keep and eliminate less desired features from a population

The driving force of this kind of evolution is human choice

Question 25

Ethical concerns on animal breeding

Answer 25

Animal cruelty and suffering derived from selective breeding animals e.g.: broiler chickens that grow quickly, but too quick that cannot support their own weight. These chickens will have numerous health problems Breeding small cats and dogs for selective breeding, they may suffer from health problems Breeders claim they provide clean, safe nutritious food (+ vaccination) for the animals to make sure they stay healthy. They also provide affordable food (diary meat) for the public

Question 26

what are homologous structures

Answer 26

structures found in different organisms that were derived from the same ancestral feature/evolutionary origin and they do not necessary serve the same function

Question 27

what are analogous structures

Answer 27

structures found in different organisms that serve similar functions but not derived from the same ancestral feature

Question 28

what did Darwin find about homologous structures

Answer 28

Darwin found a lot of homologous structures (occupy similar positions in organisms) in seemingly dissimilar species - evidence of organisms evolved from a common ancestor

Question 29

examples of homologous structures

Answer 29

Pentadactyl limbs ‘penta’ means five and ‘dactyl’ refers to fingers Mammals, birds, amphibians and reptiles all share a similar arrangement of bones in their appendages based on a five-digit limb

Question 30

what are the differences between pentadactyl limbs of humans, birds, bats, horses, whales and dolphins

Answer 30

Human hands are adapted for tool manipulation (power vs precision grip) Bird and bat wings are adapted for flying Horse hooves are adapted for galloping Whale and dolphin fins are adapted for swimming

Question 31

analogous structures examples

Answer 31

wings in birds and chicken, fins in fish and dolphin flippers, legs in insects and legs in horse

Question 32

convergent evolution features

Answer 32

Evolved from different ancestor Converge to produce analogous structures Species appearance becomes more similar over time Examples: Wings of the birds, bats and insects Fins of the fish and dolphin flippers

Question 33

divergent evolution features

Answer 33

Evolved from common ancestor Diverge to produce homologous structures Species appearance becomes more different over time Examples: Pentadactyl limb structures in vertebrates

Question 34

what is speciation

Answer 34

Speciation is an evolutionary process that results in the formation of a new species from a pre-existing species It occurs when reproductive isolating mechanisms prevent two breeding organisms from producing fertile, viable offspring

Question 35

speciation vs extinction

Answer 35

speciation increases the total number of species on Earth, and extinction decreases it

Question 36

is gradual evolutionary change in a species speciation

Answer 36

no

Question 37

Speciation example: iguanas

Answer 37

Speciation by divergence of isolated population Some iguanas got isolated on the galapagos islands and they adapted to the environment and became the only marine iguanas that can dive into the ocean to find algae for food

Question 38

what is reproductive isolation

Answer 38

Members of the same species can be prevented from reproducing because there is an insurmountable barrier between them. Eventually, the populations will change so much that the individuals from the two separate populations will not be able to reproduce with each other successfully to produce fertile offsprings.

Question 39

types of reproductive isolation

Answer 39

temporal, geographical, behavioural

Question 40

what is geographical isolation

Answer 40

Geographic isolation occurs when two populations occupy different habitats or separate niches within a common region

Question 41

example of geographical isolation

Answer 41

Plants of the same species got spread to different parts of the world and adapted to different soil pH. Those plants will not be able to grow close to each other to breed. bonobos Pan paniscus and common chimpanzees Pan troglodytes by the Congo RIver

Question 42

what is pan

Answer 42

what genus it is

Question 43

what are paniscus/troglodytes

Answer 43

what species they are

Question 44

what is temporal isolation

Answer 44

Temporal isolation occurs when two populations differ in their periods of activity or reproductive cycles

Question 45

example of temporal isolation

Answer 45

Leopard frogs and wood frogs reach sexual maturity at different times in the spring and hence cannot interbreed

Question 46

what is behavioural isolation

Answer 46

Behavioural isolation occurs when two populations exhibit different specific courtship patterns

Question 47

example of behavioural isolation

Answer 47

Certain populations of crickets may be morphologically identical but only respond to specific mating songs

Question 48

Allopatric speciation

Answer 48

Groups from an ancestral population evolve into separate species due to a period of geographical separation The two populations begin to evolve separately as a result of cumulative mutation, genetic drift and natural selection Eventually the two populations reach a degree of genetic divergence whereby they can no longer interbreed (speciation)

Question 49

sympatric speciation

Answer 49

Groups from the same ancestral population evolve into separate species without any geographical separation Sympatric speciation may result from the reproductive isolation of two populations as a result of genetic abnormalities Typically, a chromosomal error may arise which prevents successful reproduction with any organism lacking the same error

Question 50

what prevents hybridization in animals

Answer 50

Courtship behaviour often prevents hybridization in animal species. A mule is an example of a sterile hybrid

Question 51

examples of hybrids

Answer 51

liger mule zorse

Question 52

what are courtship behaviours

Answer 52

Courtship behaviours are behaviours aimed to facilitate attraction and mating with the opposite sex

Question 53

allele

Answer 53

alternate forms of the same gene

Question 54

Allopolyploid speciation

Answer 54

Allopolyploidy is a kind of polyploidy Caused by fusion of gametes of different species Increases the chance of survival in plants

Question 55

Advantages of polyploidy in plants

Answer 55

Hybrid plants formed by cross breeding same genus but different species allow the offspring to be fertile New species can be generated and they may be able to adapt to the environment very quickly and more easily with more chances of getting genetic variations (weed are well adapted to different environments) This does not need to wait for a long time to generate a new species, it can be done right at the moment of fusing of gametes (abrupt speciation)

Question 56

Adaptive radiation

Answer 56

Adaption radiation occurs when many similar but distinct species evolve relatively rapidly from a single species or form a small amount of species. This happens because variation within a population allows certain members of that population to occupy different niches. E.g. Lemus found in Madagascar, Hawaiian honeycreepers in Galapagos island - Occupy different _niche_ and _habitat_ e.g. ground, trees, rainforests, desert - _Diurnal_ and _nocturnal_ - Minimize _compe&&on_

Question 57

What does adaptive radiation allow

Answer 57

It allows closely related species to coexist without competing, thereby increasing biodiversity in ecosystems where there are vacant niches

Question 58

Speciation by polyploidy in Allium

Answer 58

Polyploidy is when an error leads to an individual having more than 2 sets of chromosomes_ - In some plant groups there is a trend for the species to have chromosome numbers that are all multiples of_one basic number_. - Most Allium species have a _diploid number that is a multiple of 16_, ancestral. Allium probably had this number. - Allium species with 32 chromosomes evolved from polyploidy, which an individual with 32 chromosomes is _tetraploid_ (4n). - If it crosses with a diploid individual, all the offspring are _infer&le triploids_(3n). - Because of this, a tetraploid is _reproduc&vely isolated_from diploids, is therefore _instant specia&on_. - Many plant species have been produced by polyploidy.