4) Natural Selection & Genetic Modification Flashcards
What does the theory of natural selection propose?
All species have evolved from simple life forms
What is involved in the process of natural selection?
Genetic variation
Survival of the fittest
Successful breeding
Best characteristics survive
What factors contributed to the slow acceptance of natural selection?
Religion
Inconclusive evidence
Genes yet to be discovered
What did genes not being discovered mean?
Darwin was unable to suggest why characteristics were passed down
What did both Wallace and Darwin have?
Island research
Joint writings
Competition
When did Wallace and Darwin produce joint writings?
1858
What is evolution defined as?
The gradual change of inherited characteristics of biological populations over time
What is evolution usually driven by?
Natural selection
What evidence is there for evolution?
Antiobiotic resistant bacteria
Fossils
How do doctors reduce new resistant strains of bacteria?
Avoid prescribing antibiotics unncessarily
Patitnets finish a course of antibiotics so all bacteria is killed
Antiobiotics in agriculture should be restricted
How do resistant strains of bacteria spread?
Mutated pathogens are resistant to antibiotics and will survive and reproduce creating bacteria which is also resistant
How many digits do animals with pentadactyl limbs have per limb?
5 digits
What are the 3 ways of forming fossils?
Preservation when decay is not possible
Mineral replacement
Hardening soft materials
How do hardening soft materials create fossils?
Hardening of soft materials can produce casts or impressions
How does mineral replacement create fossils?
Hard parts of organsisms are gradually replaced by minerals as they decay slowly creating a rock liek substance
Why is the fossil record incomplete?
Lots of early life forms were soft bodied
Geological activity has destroyed traces of ancient life
What are the oldest fossilised human remains?
Ardi (4.4 million years ago)
When was Lucy found?
3.2 million years ago
When was Leakey found?
1.6 million years ago
What do tools tell us about how evolved humans were?
More compex tools = more developed brain
What does carbon dating tell us?
When a rock was originally formed
How do you determind when a stone tool was in use?
Determine how deeply it was buried
Use known dates of other items at that level
Compare the design to other stone tools already dated
What were the 7 groups in the Traditional classification system?
Kingdom Phylum Class Order Family Genus Species
What does the 3 domain system classify organisms by?
Chemical analysis
What are the 3 domains?
Archaea
Bacteria
Eukaryota