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Question 1

What are the requirements for natural selection?

Answer 1

1. Variation: Individuals in a population vary from one another.
2. Inheritance: Parents pass on their traits to their offspring genetically.
3. Selection: Some variants reproduce more than others.
4. Time: Successful variations accumulate over many generations.

Question 2

What are phylogenetic trees?

Answer 2

Phylogenetic trees are built by identifying shared characters among organisms. These characters can be physical traits or sequence information from biological molecules.

This classification allows us to group all known life on Earth into three domains.

Question 3

What is endosymbiosis?

Answer 3

The Endosymbiosis theory states that two key organelles in eukaryotes, mitochondria and chloroplasts, are derived from bacteria. Mitochondria are derived from proteobacteria, and chloroplasts from cyanobacteria. These bacteria were engulfed by the ancestors of eukaryotes and tamed.

Question 4

What is the difference between prokaryotic and eukaryotic cells?

Answer 4

The key difference is that membrane-enclosed organelles are present in eukaryotes.