Topic 5: Checklist Questions Flashcards
State that evolution occurs when heritable characteristics of a species change.
The heritable characters change overtime and causes evolution. A change in genetic makeup also indicates evolution.
Explain how the fossil record provides evidence for evolution.
Fossil records provide evidence for evolution because it leaves traces and preserved remains. Preserved remains indicate the direct way of records and tell us the exact type of animal or origin it might have been. Traces indicates the footprints and tell us the nature of the animal.
Explain how selective breeding of domesticated animals shows that artificial selection can cause evolution.
Human intervention in artificial selection of breeding of domesticated animals plays a significant role in choosing which organism gets to breed and which does not. It is obvious that evolution has occurred due to the fact that the new species could have a significant difference from their ancestors.
Outline how the evolution of homologous structures by adaptive radiation explains similarities in structure when there are differences in function.
Adaptive radiation refers to the formation of new species in order to adapt to the environment. Thus, the change in the structure indicates the evolution of the species. The structures are similar because they are of the same ancestor and origin. But different functions because they have to adapt to the environment.
Compare the pentadactyl limb of mammals, birds, amphibians and reptiles, with different methods of locomotion.
They all have the same structure of pentadactyl limb. This indicates that they once had the same origin and ancestor. Mammals walk and uses their legs and hands to move. Birds fly and walk. Amphibians swim and walk. Reptiles swim and walk. Thus the common type of locomotion is walking and this shows that they are different functions because of the environment and adaptive radiation.
Explain how populations of a species can gradually diverge into separate species by evolution.
Physical separations of populations.
Continuous variation.
Outline how continuous variation across the geographical range of related populations matches the concept of gradual divergence.
Caught in action. Can capture how they change. No sudden changes.
Explain the development of melanistic insects in polluted areas.
In polluted areas, there is an emission of greenhouse gases, sulfur dioxide and and soot. This changes the color of tree barks to darker color. Thus, insects that are of lighter color can’t survive in these areas. Only dark colored insects can survive. Thus there are more melanistic insects in polluted areas.
Explain how natural selection can only occur if there is variation among members of the same species.
Variation: the differences in physical features of organisms.
Range of alleles present in a species accounts for the variation in the population in the population
Outline that mutation, meiosis and sexual reproduction cause variation between individuals in a species.
Causes of variation:
Mutation: any change to the DNA sequence, can range from change in a single base or the whole segment of a chromosome
Meiosis: produces gametes with alleles and thus, increases genetic variation of the species
Sexual reproduction: combination of genes results in a zygote that has genes from both of the parents
State that adaptations are characteristics that make an individual suited to its environment and way of life.
Characteristics:
Make species well adapted to its environment
If the environment changes, three genes that adapt to that environment will survive and pass onto their offspring
Outline why species tend to produce more offspring than the environment can support.
Species tend to produce more offspring than the environment can support because not everyone will survive, only the best adapted will.
State that individuals that reproduce pass on characteristics to their offspring.
Reproducing contributes passing genetic material to next generations.
Those that are not well adapted will die because of an accident or predation, and their genes alleles will be gone for good
Explain how natural selection increases the frequency of characteristics that make individuals better adapted, and decreases the frequency of other characteristics, leading to changes within the species.
This means that natural selection increases the frequency that helps the individuals adapt to the environment and decreases the frequency of other useless characteristics. This helps the whole species adapt better to the environment with time.
Explain how the beaks of finches on Daphne Major evolved.
Bigger beaks = can crack larger seeds
Smaller beaks = can crack smaller seeds
Adaptive radiation allows various finches to survive due to food variations
