The Meaning of Life
● Life: Continuous transference of energy within a system seeking perpetuation.
● Characteristics of Living Things:
○ Cells and Organization: All life is cellularly organized.
○ Response to Stimuli: Interaction with the environment.
○ Homeostasis: Maintaining internal balance.
○ Metabolism: Energy transfer through chemical reactions.
Scientific Principles and Methods
● Hypothesis, Thesis, and Theory:
1. Hypothesis: Testable explanation based on observation.
2. Thesis: Statement supported by arguments.
3. Theory: Well-substantiated and verified explanation.
● Deduction vs. Induction vs. Abduction:
1. Deduction: Conclusion is necessarily true.
2. Induction: Generalization; conclusion is likely true.
3. Abduction: Inference to the best explanation; a plausible guess.
● Scientific Method:
1. Observation
2. Formulating Questions
3. Hypothesis
4. Experiments
5. Results/Analysis (use of statistics)
6. Conclusion
Biology’s Chief Unifying Principle
● Evolution:
○ Gradual modification of populations over time.
○ Environment influences phenotype (appearance) and genotype (genetic
composition).
○ Examples:
■ Morphological Adaptation: Dolphins (mammals) and sharks (fish) adapting
similarly to aquatic life (analogous structures).
■ Homologous Structures: Shared origin, different uses (e.g., human arm
and bat wing).
■ Analogous Structures: Different origin, same use (e.g., wings of birds and
insects).
, Chemistry of Life
● Carbon: The foundation of organic molecules (except CO₂, CO, carbonates, cyanides).
● pH: Scale where each step represents a 10x change in acidity or alkalinity.
● Energy Dispenser: ATP is the molecule that stores and releases energy for cellular
functions.
● Genetic Material:
○ DNA: Contains Adenine (A), Thymine (T), Guanine (G), and Cytosine (C).
○ RNA: Uracil (U) replaces Thymine.
○ Base Pairing:
■ A pairs with T
■ G pairs with C
○ Anticodon: Complement of a codon during protein synthesis.
Cellular Processes
● Photosynthesis:
○ Converts light energy to stored chemical energy.
○ Chloroplast is the site; CO₂ is consumed, O₂ is released.
○ Types:
■ C3 Photosynthesis: Normal conditions.
■ C4 Photosynthesis: High light, temperature, and water (e.g., sugarcane).
■ CAM Photosynthesis: High temperature, low water (e.g., cacti).
● Cellular Respiration:
○ Burns sugar to release energy.
○ Involves glycolysis, the Krebs cycle, and oxidative phosphorylation.
○ Occurs in mitochondria; human cells have ~2000 mitochondria each.
● Thermodynamics:
○ 1st Law: Energy is transformed, not created or destroyed.
○ 2nd Law: Energy transfer increases disorder (entropy).
Genetics
● Mendelian Laws:
○ Law of Segregation: Alleles for each gene separate during gamete formation.
○ Independent Assortment: Genes for different traits are inherited independently.
● Key Terms:
○ Genotype: Genetic makeup (e.g., YY, Yy, yy).
○ Phenotype: Observable traits (e.g., yellow or green peas).
○ Punnett Square: Tool for predicting genetic outcomes.
● Life: Continuous transference of energy within a system seeking perpetuation.
● Characteristics of Living Things:
○ Cells and Organization: All life is cellularly organized.
○ Response to Stimuli: Interaction with the environment.
○ Homeostasis: Maintaining internal balance.
○ Metabolism: Energy transfer through chemical reactions.
Scientific Principles and Methods
● Hypothesis, Thesis, and Theory:
1. Hypothesis: Testable explanation based on observation.
2. Thesis: Statement supported by arguments.
3. Theory: Well-substantiated and verified explanation.
● Deduction vs. Induction vs. Abduction:
1. Deduction: Conclusion is necessarily true.
2. Induction: Generalization; conclusion is likely true.
3. Abduction: Inference to the best explanation; a plausible guess.
● Scientific Method:
1. Observation
2. Formulating Questions
3. Hypothesis
4. Experiments
5. Results/Analysis (use of statistics)
6. Conclusion
Biology’s Chief Unifying Principle
● Evolution:
○ Gradual modification of populations over time.
○ Environment influences phenotype (appearance) and genotype (genetic
composition).
○ Examples:
■ Morphological Adaptation: Dolphins (mammals) and sharks (fish) adapting
similarly to aquatic life (analogous structures).
■ Homologous Structures: Shared origin, different uses (e.g., human arm
and bat wing).
■ Analogous Structures: Different origin, same use (e.g., wings of birds and
insects).
, Chemistry of Life
● Carbon: The foundation of organic molecules (except CO₂, CO, carbonates, cyanides).
● pH: Scale where each step represents a 10x change in acidity or alkalinity.
● Energy Dispenser: ATP is the molecule that stores and releases energy for cellular
functions.
● Genetic Material:
○ DNA: Contains Adenine (A), Thymine (T), Guanine (G), and Cytosine (C).
○ RNA: Uracil (U) replaces Thymine.
○ Base Pairing:
■ A pairs with T
■ G pairs with C
○ Anticodon: Complement of a codon during protein synthesis.
Cellular Processes
● Photosynthesis:
○ Converts light energy to stored chemical energy.
○ Chloroplast is the site; CO₂ is consumed, O₂ is released.
○ Types:
■ C3 Photosynthesis: Normal conditions.
■ C4 Photosynthesis: High light, temperature, and water (e.g., sugarcane).
■ CAM Photosynthesis: High temperature, low water (e.g., cacti).
● Cellular Respiration:
○ Burns sugar to release energy.
○ Involves glycolysis, the Krebs cycle, and oxidative phosphorylation.
○ Occurs in mitochondria; human cells have ~2000 mitochondria each.
● Thermodynamics:
○ 1st Law: Energy is transformed, not created or destroyed.
○ 2nd Law: Energy transfer increases disorder (entropy).
Genetics
● Mendelian Laws:
○ Law of Segregation: Alleles for each gene separate during gamete formation.
○ Independent Assortment: Genes for different traits are inherited independently.
● Key Terms:
○ Genotype: Genetic makeup (e.g., YY, Yy, yy).
○ Phenotype: Observable traits (e.g., yellow or green peas).
○ Punnett Square: Tool for predicting genetic outcomes.
