Biology 112 Unit One Notes

Properties of Living Things

  • Order: Structured organization in biological systems.

  • Regulation: Homeostasis, maintaining internal stability.

  • Growth and Development: Organisms grow and mature over time.

  • Energy Utilization: Metabolism, conversion of energy for work.

  • Response to the Environment: Adaptation and reaction to changes.

  • Reproduction: Ability to reproduce and pass on genetic information.

  • Evolution: Adaptation over generations through natural selection.

Structural Organization of Life

  • Biosphere: Entire planet.

  • Ecosystem: Interactions between biotic and abiotic factors.

  • Community: All organisms in a specific area.

  • Population: Group of individuals of the same species.

  • Organism: Individual living entity.

  • Organ Systems: Groups of organs working together (e.g., digestive system).

  • Organs: Structures within organ systems (e.g., brain).

  • Tissues: Groups of similar cells (e.g., nervous tissue).

  • Cells: Smallest unit of life.

  • Molecules: Groups of atoms bonded together.

  • Atoms: Basic units of matter.

Prokaryotic vs. Eukaryotic Cells

  • Prokaryotic Cells: Lack a nucleus, do not have membrane-bound organelles.

  • Eukaryotic Cells: Have a nucleus, membrane-bound organelles, generally larger.

Classification of Life (Linnaean System)

  • Domain: Highest level of classification.

  • Kingdom: Major category (e.g., Animalia, Plantae).

  • Phylum/Division: Groups of related organisms.

  • Class, Order, Family, Genus, Species: More specific classifications.

Evolution and Natural Selection

  • Defined as inherited changes over time in populations.

  • Natural Selection: Mechanism behind evolution, favoring traits that improve survival.

Scientific Method

  • A structured approach to inquiry, including observation, hypothesis formulation, experimentation, and conclusion.

  • Hypotheses should be falsifiable and tested repeatedly.

Atomic Composition

  • Atoms consist of:

    • Protons: Positive charge.

    • Neutrons: No charge.

    • Electrons: Negative charge.

  • Molecules: Combinations of two or more atoms.

  • Compounds: Substances with distinct ratios of elements (e.g., H2O).

Chemical Bonds

  • Covalent Bonds: Atoms share electrons (can be polar or nonpolar).

  • Ionic Bonds: Electrons transferred between atoms, creating charged ions.

  • Hydrogen Bonds: Weak attractions between polar molecules (e.g., water).

Properties of Water

  • Cohesion and adhesion affect capillary action.

  • Water has high specific heat capacity and acts as a versatile solvent.

pH and Acidity

  • pH measures hydrogen ion concentration, impacting the acidity or basicity of a solution.

  • Buffers help maintain stable pH levels in biological systems.

Chemical Reactions

  • Involve the transformation of reactants into products (e.g., Na + Cl → NaCl).

Importance of Water

  • Essential for life; supports metabolic reactions, temperature moderation, and acts as a solvent for many biological substances.