Evolution

Question 1

Theory of evolution

Answer 1

Life on Earth began as the simple organism from which all the more complex organisms evolved, by the process of natural selection.

Question 2

Natural selection

Answer 2

Individuals with more successful characteristics, suited for the particular environment have better chance to survive, reproduce and pass the useful characteristics to the offsprings.

Question 3

Mutation

Answer 3

Is a change in an organism’s DNA. Mutations can be beneficial by producing useful characteristics. It happens randomly, but for example, excess UV light can increase the rate

Question 4

Classifying organisms

Answer 4

Looking at the similarities and differences between organisms allows us to classify them into groups.

Question 5

How long is the life on earth?

Answer 5

more than 3 billion years

Question 6

Lamarck’s theory and other theories of evolution

Answer 6

Based mainly on the idea that changes that occur in an organism during its lifetime can be inherited and passed on the offsprings. We know now that in the vast majority of cases it cannot happen.

Question 7

Individual organisms with a particular species…

Answer 7

may show a wide range of variation because of difference in their genes.

Question 8

Development of a new species

Answer 8

• isolation: two populations of species become separated (geographically)
• genetic variation: each population has a wide range of alleles that control their characteristics
• natural selection: in each population, useful alleles are passed on offsprings
• speciation: populations become so different that successful interbreeding is no longer possible

Question 9

Genetic variation

Answer 9

Different characteristics as a result of mutation or reproduction, because of a new combination of genes

Question 10

Environmental variation

Answer 10

Different characteristics caused by an organism’s environment(acquired characteristics)

Question 11

Continuous variation

Answer 11

There is a gradual transition between the two extremes. This feature is usually sowed by a number of different genes and is also affected by the environment. (height, foot size, weight, intelligence)

Question 12

Discontinuous variation

Answer 12

Some characteristics are either present or not. These characteristics are often determined by a single gene or chromosome and there is a little or no environmental impact on the features(sex, blood group)