BIOL_2102-1001-Descent_with_Modification-1

Overview of Course

• Course Title: Principles of Biology: Organisms to Ecosystems

• Course Code: BIOL 2102

• Meeting Times:

  • MWF 9:00 AM – 9:50 AM (001)

  • MWF 2:00 PM – 2:50 PM (002)

• Syllabus: Full syllabus available on UNM Learn (Canvas)

• Importance of Acknowledgment:

  • Honors the traditional lands of the Pueblo of Sandia and recognizes contributions of Indigenous peoples.

Introduction to Descent with Modification

• Key Questions:

  • Why do children resemble their parents?

  • Do children look identical to their parents? Why or why not?

  • Do full siblings look identical to each other? Why or why not?

• These questions center on genetic inheritance and variation.

Levels of Biological Organization

Basic Levels

• Molecules

• Organelles

• Cells

• Tissues

• Organs

• Organisms

• Populations

• Communities

• Ecosystems

• Biosphere

• Each level exhibits distinct emergent properties.

Understanding Deep Time

Historical Events in Life

• Formation of Earth: Approximately 4.6 billion years ago

• First evidence of life: Approximately 2.5 billion years ago

• Cambrian explosion: Approximately 542 million years ago

• K-Pg extinction: Approximately 65.5 million years ago

• First Homo sapiens: Approximately 300,000 years ago

• First cities: Approximately 9,500 years ago

Hereditary Traits and Phenotypes

• Phenotype Definition: Manifestation of an organism's traits.

• Observation Trends:

  • Offspring resemble parents in phenotype but are not identical.

  • Correlation exists between phenotype and genotype.

Inheritance Models

Blending Model vs Segregating Model

• Blending Model (H1): Traits of offspring are intermediates of parents' traits.

• Segregating Model (H2): Offspring express traits of one parent or the other.

Example Scenario

• Random mating between large blue bats and small red bats over 100 generations reinforces these patterns of inheritance.

Mendelian Genetics

• Describes trait inheritance as either blending or segregating.

• Modern Genetics Insight: Traits are encoded by genes, leading to diverse phenotypes.

Evolutionary Principles

Key Features Required for Evolution

• Variation: Organisms display an array of traits.

• Heritability: Offspring resemble parent's traits.

• Differential Fitness: Organisms with varying traits have different reproductive success.

Further Exploration

• Recommend exploring related courses:

  • BIOL 2101 (Molecules to Cells)

  • BIOL 300C (Evolution)

  • BIOL 302C (Genes to Genomes)

  • BIOL 419 (Astrobiology)

Vocabulary Review

Key Terms for Understanding

• Central dogma of biology: DNA -> RNA -> Protein

• Phenotype: Observable traits of an organism.

• Blending model of inheritance: Offspring traits blend between parents.

• Segregating model of inheritance: Offspring traits segregate from parents.

• Gene: Unit of heredity in organisms.

Levels of Biological Organization Review

• Choose five levels and describe their significance and examples.

Historical Events Review

Major Dates to Remember

• ~9,500 BP: Emergence of first cities.

• ~300,000 BP: Appearance of first Homo sapiens.

• ~65,500,000 BP: K-Pg extinction event.

• ~542,000,000 BP: Cambrian explosion.

• ~2,500,000,000 BP: First evidence of life.

Inheritance Models Discussion

• Understand blended traits in blending inheritance.

• Recognize segregated traits in segregating inheritance.

• Analyze expected offspring variety after 100 generations of random mating.