Evolution
1. What does evolution mean?
Evolution means living things change over many generations.
1. What is a fossil?
A fossil is the preserved remains or traces of an ancient organism.
1. What is speciation?
Speciation is when one species splits into two or more new species.
What is the main purpose of the Hardy-Weinberg principle?
To show when a population is not evolving.
What is stabilizing selection.
When the average trait is favored.
2. What is a mutation, and why is it important for evolution?
A mutation is a change in DNA; it creates new traits that can be passed on.
2. How does the fossil record support evolution?
The fossil record shows changes in organisms over time and provides examples of extinct species and transitional forms.
2. What is one main cause of speciation?
Being separated by a barrier, like a mountain or river, can cause speciation.
What are the 5 conditions needed for Hardy-Weinberg principle?
No mutations, no migration, random mating, large population, no natural selection.
What is directional selection?
When one extreme trait is favored.
3. What is the difference between homologous and analogous structures?
Homologous structures come from a common ancestor; analogous structures do not, but look or work the same.
3. What are homologous structures, and how do they support the idea of common ancestry?
Homologous structures are body parts in different species that are similar in structure because they come from a common ancestor, showing relatedness.
3. What is reproductive isolation?
Reproductive isolation is when groups of the same species can’t mate with each other anymore.
What is a genetic drift?
A random change in allele frequencies (happens more in small populations).
What is disruptive selection?
4. What is speciation, and what is one way it can happen?
Speciation is when one species splits into two; it can happen if a group gets separated and changes over time.
4. How does comparing embryos (embryology) provide evidence for evolution?
Many animals look similar as embryos, which suggests they share a common ancestor and have similar developmental pathways.
4. What is the difference between allopatric and sympatric speciation?
Allopatric speciation happens when groups are separated by a physical barrier; sympatric speciation happens without a barrier.
What is gene flow?
Movement of genes into or out of a population (like individuals moving).
What is sexual selection?
When traits help an organism attract a mate.
5. How does DNA evidence support the theory of evolution?
DNA shows how closely related different species are and helps scientists track how species have changed over time.
5. Why is molecular evidence, such as DNA and protein comparisons, considered one of the strongest proofs of evolution?
Molecular evidence shows similarities and differences at the genetic level, revealing exactly how closely related different species are and tracing the evolutionary changes that have happened over time
5. How can changes in mating behavior lead to speciation?
If groups start preferring different mates or mating at different times, they can become separate species over time.
What does p2+2pq+q2=1 represent?
Genotype frequencies in a population (AA, Aa, Aa).
What is artificial selection?
When humans choose which traits get passed on (like dog breeding).