University:
High School
Course:
High School Biology
Academic year:

2019
Views:

144

Pages:

7
Author:

StellarStrategist

Evolution - Background Evolution = a genetic change in a population over many generations. Essential Questions 1. Why is genetic Diversity among individuals so important for the survival of a species? 2. What is the definition of a species? 3. What is the revised scientific definition of evolution? Can you see evolution? Terms to Know • • • • • Species – group of individuals that can interbreed in nature and produce fully fertile offspring Population - All of the individuals of the same species that live in the same area. Biodiversity – many different types of life in an area Genetic Diversity – many different types of genotypes in a population Mutations - changes in a DNA sequence – • can be Good, Bad or Neutral Universal Genetic Code – ALL living things have DNA and use the same 20 amino acids to make all of their proteins What is Evolution? • Definition: A gradual process in which something changes into a different and usually more complex or better form • Darwin’s: All organisms have descended from a common ancestor by modifying over time. • **Revised: A genetic change in a population over many generations. • Populations evolve, not individuals! The Earth is old! • Early Earth = very different from today • Earth = 4.6 billion years old • The Earth and life on Earth are still changing • Life has existed on Earth for ~3.6 billion years. • Life has changed over time – Simple  Complex – Prokaryote  Eukaryote Why Biodiversity/Genetic Diversity Is Important • Variation in a population = many different phenotypes • Each phenotype allows individuals to respond differently to a changing environment • This increases the chance that some members of the population will survive a major environmental change or catastrophe – This is like insurance against extinction!