Topic 4 - Natural Selection And Genetic Modification

Question 1

What did Charles Darwin’s theory of natural selection propose ?

Answer 1

all species have evolved from simple life forms that first appeared on Earth more than three billion years ago

Question 2

What is the process of the theory of natural selection ?

Answer 2

Genetic variation
Survival of the fittest
Successful breeding
Best characteristics survive

Question 3

What is genetic variation?

Answer 3

Different individual animals in a population (or species) have different combinations of genes (show genetic variation)

Question 4

What is survival of the fittest ?

Answer 4

Individuals that are best adapted to the environment will have a greater chance of survival.

Question 5

What is successful breeding ?

Answer 5

Individuals with the best chances of survival are the most likely to breed successfully (because they survive)

Question 6

What is ‘best characteristics survive’ ?

Answer 6

The characteristics responsible for the greater chance of survival are more likely to be passed on to the next generation

Question 7

At the time, Darwin’s ideas were met with significant opposition from the scientific community.

What factors contributed to the slow acceptance of his ideas ?

Answer 7

Religion
Genes yet to be discovered
Inconclusive evidence

Question 8

Why is religion against the theory of natural selection?

Answer 8

Natural selection challenged the common belief that God created the natural world

Question 9

How does genes yet to be discovered go against the theory of natural selection ?

Answer 9

At the time, genes had not been discovered and Darwin was unable to suggest a method for the passing of characteristics between generations (from parent to child).

Question 10

How does Inconclusive evidence go against the theory of natural selection?

Answer 10

There were scientists that regarded the evidence presented by Darwin as inconclusive

Question 11

Who wrote to Darwin in 1858, expressing his similar thinking about natural selection ?

Answer 11

Alfred Russel Wallace

Question 12

Wallace and Darwin Both had spent a significant amount of time on islands, how did this help their research on evolution ?

Answer 12

the isolation of island populations leads to enhanced speciation (the formation of new species) rates.

Question 13

In what year did, the two combined their great minds to produce joint writings ?

Answer 13

1858

Question 14

What was the writing published by Darwin called ?

Answer 14

‘On The Origin of Species’

Question 15

What year was ‘On The Origin of Species’ published ?

Answer 15

1859

Question 16

In what year did Darwin and Wallace produce joint writings?

Answer 16

1858

Question 17

What is evolution ?

Answer 17

The gradual change of inherited characteristics of biological populations over time

Question 18

How has the theory of evolution greatly affected modern biology?

Answer 18

Genetics

Modern biology

Question 19

How has the theory of evolution (genetics) greatly affected modern biology?

Answer 19

Scientists later discovered exactly how traits are inherited; through genes.

Genetics is now a huge area of biology

Question 20

How has the theory of evolution (evolutionary biology) greatly affected modern biology?

Answer 20

Many scientists have since studied how organisms have changed over time, and also how different species are related to each other

Question 21

Which area of biology wouldn’t exist without the theory of evolution?

Answer 21

Genetics

Question 22

What supports the theory of evolution?

Answer 22

The discovery of genes as a mechanism (way) to inherit characteristics and create variance

Antibiotic resistant bacteria

Fossils

Question 23

How do antibiotic resistant bacteria support the theory of evolution?

Answer 23

Natural selection neatly explains this phenomenon:

Bacteria reproduce rapidly.

Mutations occur during reproduction.

If a mutated bacterium is resistant to antibiotics, it will survive exposure to antibiotics and go on to reproduce.

This bacterium will represent the original ancestor of a new resistant strain.

Question 24

How do fossils support the theory of evolution?

Answer 24

Fossils show the gradual changes in organisms over vast periods of time.

Question 25

What measures must be taken to reduce the emergence of new antibiotic resistance strains ?

Answer 25

Doctors should avoid prescribing antibiotics unnecessarily, for example for treating non-serious or viral infections.

Patients must finish a course of antibiotics to make sure that all of the bacteria are killed.

The use of antibiotics in agriculture (for example, cattle feed), should be restricted.

Question 26

What’s an example of an antibiotic resistant bacteria ?

Answer 26

MRSA

Question 27

Is the development of new antibiotics slow and expensive ?

Answer 27

Yes

Question 28

Fact

Answer 28

Antibiotics struggle to keep up with the emergence of new strains

Question 29

How is a Resistant strain of bacteria produced ?

Answer 29

If a mutated bacterial pathogen is resistant to antibiotics, when a person is treated with antibiotics, the bacteria will survive and go on to reproduce.

This bacteria is the original ancestor of a new resistant strain.

This bacteria will spread, as there will be no treatment for it, and people are not immune to it (as they were previously treated with antibiotics).

Question 30

Bacteria reproduce and evolve:

Answer 30

Rapidly

Question 31

By comparing similar structures in similar animals, we may be able to prove what ?

Answer 31

that these organisms have evolved from the same organism.

An example of this is the pentadactyl limb (which means five digits or fingers).

Many vertebrates (animals with backbones) have a very similar bone structure, even though their limbs look very different from the outside.

This is because organisms have evolved to different lifestyles in different places.

Question 32

Which animals have pentadactyl limbs?

Answer 32

Looking at the skeletons of animals shows that most vertebrates (animals with backbones) have pentadactyl limbs.

The hooves of horses, flippers of whales, wings of birds and the feet of frogs and lizards all have five digits.