Biology - Tue1 - Genes, Inheritance and Selection

What is natural selection?

Process where individuals with traits best suited for their environment, survive and reproduce.

What causes variation (differences) within a species?

A variety of alleles (different forms of genes) formed by mutations (a change in DNA that can create new traits)

Why is there a struggle for survival among organisms?

Organisms produce more offspring than the environment can support, leading to competition for resources.

What happens to individuals with characteristics best suited for their environment?

They survive more, reproduce more, and pass on their alleles at a higher rate.

What term did Darwin use for individuals best suited for survival?

Survival of the Fittest

How does natural selection lead to evolution?

Over generations, advantageous features become more common, changing the species’ characteristics.

What is evolution?

Change in adaptive features of a population over time.

What happens if two populations of a species evolve differently enough?

They may no longer interbreed to produce offspring and form two new species.

Give an example of natural selection in animals

The peppered moth changed colour to survive pollution.

What evidence supports evolution through natural selection.

Fossils, human evolution remains and antibiotic resistant bacteria.

How can fossils show evolutionary change?

Dating (finding the age of a fossil or rock) shows changes in species.

Who are some key fossil hominids (early humans) in human evolution?

Ardi, Lucy, Turkana Boy

What key traits show that Ardi was between an ape and a human?

She had: an ape like big toe, short legs, long arms, chimpanzee sized brain, and she walked upright.

What traits show that Lucy was more human like than Ardi?

Lucy had: arched feet, partially human like arms and legs, slightly larger brain, walked upright.

How does antibiotic (medicine that kills bacteria) resistance show evolution?

Bacteria with a mutation that resists the antibiotic, survive, reproduce, and gradually most bacteria become resistant.

Who developed the theory of natural selection?

Charles Darwin

What was Wallace’s contribution?

Studied warning coloration (colours that warn predators if an animal is dangerous) and published work on natural selection and speciation (formation of a new species)

How does evolution help modern biology?

It explains evolution, common ancestry, species classification, and guides biodiversity conversation (protecting the variety of species)

What is the purpose of seed banks?

To store genetic diversity (variety of genes) of plants, saving alleles (different forms of a gene) for traits like pest (plants ability to survive insects eating it) resistance and drought resistance (plants ability to surive with little water)

Define adaptation in evolution

A feature that increases an organism’s chance of survival or reproduction.