PPT 1

BSC1010C: General Biology 1 Study Notes

INTRODUCTION CHAPTER

LIFE AND SCIENTIFIC PRINCIPLES (Chapter 1 B2E)
MODULE 1 - WEEK 1

LEARNING OBJECTIVES

  • By the end of this section, you will be able to:

    • Identify and describe the properties of life.

    • Describe the levels of organization among living things.

    • Describe the 3 theories that form the framework for modern biological science.

    • Summarize the steps of the scientific method.

    • Compare inductive reasoning with deductive reasoning.

KEY THEMES IN BIOLOGY

  • What does it mean to say that something is alive?

    • Life is cellular.

    • Life evolves.

    • Life processes information.

  • These ideas predict the tree of life and structure biological thought.

WHAT IS BIOLOGY?

  • Definition: Biology is the study of life and living organisms.

    • Explores structure, function, growth, interactions of living organisms.

    • Encompasses evolution, from microscopic cells to global ecosystems.

    • Measurement: 1 micrometer (µm) = one-millionth (1/1,000,000) of a meter (m).

PROPERTIES OF LIFE

Distinct Characteristics Shared by Living Organisms:

  1. Order

    • Highly organized structures composed of one or more cells.

    • Arrangement from atoms to molecules, organelles, cells, tissues, organs, and systems.

  2. Response to Stimuli

    • Organisms react to environmental changes.

    • Examples include:

      • Plants growing towards light (phototropism).

      • Bacteria moving away from toxins.

    • Function enables adaptation and survival.

  3. Reproduction

    • Organisms reproduce to continue species, can be either:

      • Asexual (single parent) or sexual (two parents).

  4. Adaptation

    • Organs evolve traits suited for their environment through natural selection.

    • Enhances survival and reproductive success (e.g., stick insect, chameleon).

  5. Growth and Development

    • Organisms process hereditary information via genes.

    • Controlled by genetic instructions, involving cell division and differentiation.

    • Example: tadpole developing into a frog.

  6. Regulation/Homeostasis

    • Maintaining stable internal conditions (e.g., body temperature, blood glucose level).

    • Achieved through feedback mechanisms.

  7. Energy Processing

    • Organisms acquire and use energy for life's processes.

    • Metabolism: sum of all chemical reactions.

    • Categories: Autotrophs (producers) vs. Heterotrophs (consumers).

HIERARCHY OF BIOLOGICAL ORGANIZATION

Levels of Organization (in order from smallest to most complex):

  1. Atoms

  2. Molecules

  3. Macromolecules

  4. Organelles

  5. Cells

  6. Tissues

  7. Organs and organ systems

  8. Organisms

  9. Populations and communities

  10. Ecosystems

  11. Biosphere

Explanation of Each Level:

  1. Atoms: Smallest unit of an element retaining its properties.

  2. Molecules: Compounds of one or more atoms.

  3. Macromolecules: Large, complex molecules with biochemical functions.

  4. Organelles: Specialized compartments within cells performing specific functions.

  5. Cells: Basic units of life that exhibit all characteristics of living things.

  6. Tissues: Groups of similar cells performing a specific function.

  7. Organs: Structures made of various tissues working together.

  8. Organ Systems: Groups of organs functioning together.

  9. Organisms: Individual living entities.

  10. Populations: Individuals of the same species in a defined area.

  11. Communities: All populations interacting within an ecosystem.

  12. Ecosystem: Interaction of living and non-living components.

  13. Biosphere: The global sum of all ecosystems; includes land masses, water bodies, and atmosphere.

LINNAEUS’ TAXONOMIC SYSTEM OF CLASSIFICATION

  • In 1735, Carolus Linnaeus established a classification system for organisms.

  • Each organism given a unique two-part scientific name:

    • Genus: Group of closely related species.

    • Species: Individuals that can breed together and retain distinct characteristics.

  • Rules of Nomenclature:

    • Scientific names italicized, genus capitalized, species not capitalized (e.g., Homo sapiens).

TAXONOMY

  • Definition: The effort to name and classify organisms into a taxon (named group).

  • Most inclusive group: Domain.

    • Three domains include:

    • Bacteria

    • Archaea

    • Eukarya

  • Eukarya consists of 4 Kingdoms:

    • Protista (mostly single-celled Eukaryotes)

    • Fungi (fungus)

    • Plantae (plants)

    • Animalia (animals)

TAXONOMIC RANKS

  • Hierarchical groupings from broad to specific:

    • Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

    • Mnemonics: "King Philip Came Over For Good Soup".

Taxon Example:

  • Domain: Eukarya

  • Kingdom: Animalia

  • Phylum: Chordata

  • Class: Mammalia

  • Order: Carnivora

  • Family: Canidae

  • Genus: Vulpes

  • Species: Vulpes vulpes (Red fox).

THEORIES FORMING THE FRAMEWORK FOR MODERN BIOLOGICAL SCIENCE

  1. The Cell Theory

    • States that:

      • All organisms are made of cells.

      • All cells come from preexisting cells.

    • Proposed by Robert Hooke and Anton van Leeuwenhoek.

  2. Theory of Evolution

    • Proposed by Charles Darwin and Alfred Russel Wallace.

      • States that all species are related by common ancestry and characteristics can change through generations.

      • Descent with modification.

    • Natural Selection: Explains how evolution occurs.

  3. Chromosome Theory of Inheritance

    • Proposed by Walter Sutton and Theodor Boveri in 1902.

      • Genetic information is encoded in genes located on chromosomes.

      • Genes are segments of DNA responsible for traits.

      • DNA is the hereditary material.

THE SCIENTIFIC METHOD

  • Components of the scientific process include:

    • Discovery Science: Observations leading to generalizations.

    • Induction: Drawing general conclusions from many observations.

    • Hypothesis-Based Science: Formulating explanations based on observations.

    • Deduction: Testing specific predictions based on general principles.

    • Drives experimentation often framed as "If, then" statements.

STEPS OF SCIENTIFIC METHOD

  1. Make an observation.

  2. Ask a question.

  3. Formulate a hypothesis.

  4. Make a prediction based on the hypothesis.

  5. Conduct experiments to test the prediction.

  6. Analyze results.

  7. Report results or revisit hypotheses based on findings.

INDUCTIVE AND DEDUCTIVE REASONING

  • Inductive Reasoning: Generalizes conclusions from specific observations.

  • Deductive Reasoning: Uses general principles to forecast specific outcomes.

  • Clarifying the relationship, where inductive conclusions can inform deductive premises.

NOTE: Ensure to constantly refer back to this guide for detailed information about biological principles, theories, the scientific method, and their applications. The comprehensive information here aims to cover various aspects of General Biology 1 (BSC1010C) to facilitate understanding and retention of course materials.