evolution

Question 1

Genetic variation

Answer 1

Different individuals animals in a population(or species) have different combinations of genes.

Question 2

Survival of the fittest

Answer 2

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

Question 3

Successful breeding

Answer 3

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

Question 4

Characteristics

Answer 4

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

Question 5

Name three reasons why natural selection was controversial?

Answer 5

• genes yet to be discovered
• religion (God created the world)
• inconclusive evidence

Question 6

Natural selection was theorised by Charles Darwin, what did he theorise?

Answer 6

That all all species have evolved from simple life forms that appeared on earth more than 3 billion years ago

Question 7

What were the impacts of the theory of evolution?

Answer 7

• evolutionary biology - many scientists have studied how organisms have changed over time, and also how different species are related to each other.
• genetics- scientists later discovered exactly how traits are inherited; through genes, genetics is now a huge area of biology.

Question 8

What is evolution?

Answer 8

the gradual change of a the inherited characteristics of biological populations over time.

Question 9

How are fossils evidence for evolution?

Answer 9

• show the gradual change in organisms over vast periods of time

Question 10

How are antibiotic resistant bacteria evidence for evolution?

Answer 10

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 11

By comparing similar structures in similar animals, we may be able to prove that these organisms have evolved from the same organism. What is an example of this?

Answer 11

Pentadactyl Limbs (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 12

Name three ways of forming fossils:

Answer 12

• hardening soft materials- the hardening of soft materials can produce casts or impressions such as footprints: for example, clay hardens around an organism that is buried within it. This organism decays, leaving behind a cast of itself
• preservation when decay is not possible- where decomposers cannot act, preservation is possible. Decomposers cannot operate in glaciers (extreme, low temperatures) and peat bogs (extreme acidity).
• mineral replacement- hard parts of organisms are gradually replaced by minerals as they decay slowly, creating a rock-like substance. When the surrounding sediment turns to rock, the teeth-shaped mineral structure remains distinct (different).

Question 13

definition of fossils

Answer 13

the remains of traces of ancient life

Question 14

two places where decay isn’t possible:

Answer 14

• glaciers

- peat bogs

Question 15

The traditional classification system, devised by Carl Linnaeus, categorises organisms based on their structure and characteristics. The order of the classification system is: (HINT- King Prawn Curry Or Fried Greasy Sausage)

Answer 15

• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

Question 16

Carl Woese proposed the 3 domain system. This classifies organisms based on chemical analysis. What are the three domains?

Answer 16

• Archaea - primitive bacteria, many of which are extremophiles i.e. live in extreme environments
• Bacteria - true bacteria.
• Eukaryota - organisms possessing complex sub-cellular structures (protists, fungi, plants & animals).