Biology 105/106: Exam 1 Study Material

This document outlines key concepts for Biology 105/106 Exam 1, covering fundamental principles of science, life, cells, metabolism, and energy, along with essential lab topics.

Chapter 1: The Scientific Process

• Science as a Process:
  1. Observation: Noticing phenomena.
  2. Question: Forming a formal hypothesis.
  3. Hypothesis: A testable explanation for an observation.
  4. Experimentation: Testing the hypothesis.
  5. Data Analysis: Drawing conclusions from results.
  6. Communication: Sharing findings and restarting the process with new questions.
• Hypothesis vs. Prediction: Understand the distinction.
• Experiments:
  • Controls: Elements kept constant to ensure valid results.
  • Variables:
    • Independent Variable: The factor manipulated by the experimenter.
    • Dependent Variable: The factor measured or observed, which may change in response to the independent variable.
• Results Displayed by Graphs:
  • Bar Graphs: Used for categorical independent variables and measured dependent variables.
  • Histograms: Similar to bar graphs but used for continuous independent variables, showing counts or frequency for the dependent variable.
  • Line Graphs: Illustrate functional relationships (where X depends on Y). Remember: correlation does not imply causation!
• Scientific Theory: An explanation supported by multiple lines of evidence, with no evidence against it.
• Examples of Scientific Theories:
  • Cell Theory: States that all living organisms are made of cells.
  • Theory of General Relativity: Describes gravitation and spacetime.
  • Theory of Evolution by Natural Selection: Explains how organisms best adapted to their environment tend to survive and reproduce, passing on their traits.

Chapter 2: The Chemistry of Life

• Five Functional Traits of Life: All living organisms:
  1. Grow
  2. Reproduce
  3. Maintain Homeostasis
  4. Sense & Respond to Stimuli
  5. Obtain & Use Energy
• Matter and Molecules:
  • All matter is made of elements.
  • Elements combine to form molecules.
  • Molecules containing covalently bonded Carbon, Hydrogen, and Oxygen are considered organic.
• Four Types of Organic Molecules (Macromolecules): Life is composed of:
  • Lipids
  • Proteins
  • Carbohydrates
  • Nucleic Acids
• Organic Molecule Characteristics: Carbon-based backbone with at least one Carbon-Hydrogen bond (C, H, O, N are common elements).
• Macromolecules, Subunits, and Biological Uses:
  • Carbohydrates:
    • Subunits: Monosaccharides (simple sugars, e.g., glucose)
    • Biological Uses: Energy storage, structural support
    • Examples: Starch & glycogen (storage), cellulose (cell walls)
  • Lipids:
    • Subunits: Fatty acids, sterols (not true monomer-polymers; all lipids are hydrophobic)
    • Biological Uses: Energy storage, hormones, cell membranes
    • Examples: Triglycerides ("fats"), estrogen, phospholipids & cholesterol
  • Proteins:
    • Subunits: Amino acids
    • Biological Uses: Enzymes, cell membrane structures, cellular movement
    • Examples: Catalase, membrane channels & pores
  • Nucleic Acids:
    • Subunits: Nucleotides
    • Biological Uses: Information storage
    • Examples: DNA, RNA
• Cell Membrane Composition: Cells are primarily water, with phospholipids (mainly) and proteins (less numerous) forming a barrier between the intracellular and extracellular environments.

Chapter 3: Cell Structure and Function

• Cell Theory Revisited:
  • All living things are made of cells.
  • Cells arise from other cells.
• Basic Classification of Living Organisms by Cell Type:
  • Prokaryotic Cells: Lack membrane-bound organelles. They do contain ribosomes (for protein synthesis) and DNA. Example: Bacteria.
  • Eukaryotic Cells: Contain membrane-bound compartments called organelles. Examples: Animals, plants, fungi, protists.
• Key Organelles and Their Functions:
  • Nucleus: The "brain" or "memory bank"; stores genetic information (DNA).
  • Rough Endoplasmic Reticulum (RER): Houses ribosomes; involved in protein synthesis and modification.
  • Smooth Endoplasmic Reticulum (SER): Involved in lipid synthesis and detoxification.
  • Golgi Body (Apparatus): Packages molecules for movement within or out of the cell (like an "Amazon Warehouse").
  • Vesicle: Transport compartment (like "FedEx trucks").
  • Mitochondria: The "power plants"; convert energy from food into cellular energy (ATP).
  • Chloroplasts: (Autotrophic eukaryotes only) Convert electromagnetic energy (light) into chemical energy via photosynthesis.
  • Lysosomes: The "recycling centers"; break down old cellular parts.
  • Cell Wall: (Plants, bacteria, fungi, algae only; not animal cells or some protists) A rigid protective outer structure.
• Membrane Transport:
  • Diffusion: Movement of molecules from an area of high concentration to an area of low concentration.
  • Osmosis: A specific case of diffusion involving water molecules across a semi-permeable membrane (often cell membranes).
  • Solution: A mixture of one or more molecules within a liquid.
  • Solute: The molecules dissolved into a solution.
  • Solvent: The main liquid component of a solution.
  • Tonicity: The relative abundance of solutes within a solution, usually comparing two solutions.
    • Hypotonic: Having a lower solute concentration than another solution.
    • Hypertonic: Having a greater solute concentration relative to another solution.
    • In plant and bacterial cells, rigid cell walls prevent bursting due to water influx from osmosis, leading to turgor pressure in plants, which allows upright growth.

Chapter 4: Metabolism and Enzymes

• Enzyme Function in Metabolism: Enzymes act as catalysts, speeding up chemical reactions by lowering their activation energy.
• Instruction: Be able to write a hypothesis based on your observation of infographic 4.1 (Hunger Map) on page 77 of the textbook.

Chapter 5: Energy and Photosynthesis

• Commonality of Algae, Plants, and Cyanobacteria: All perform photosynthesis.
• Color Reflected by Plants: Plants reflect green light photons.
• Why Plants are Autotrophs: Plants are autotrophs because they capture sunlight energy through photosynthesis to build their own organic molecules.
• Energy Flow from Sun to Wolf (Conservation of Energy): Energy cannot be created or destroyed, only transformed. Sunlight energy is captured by plants (producers) through photosynthesis, converting it into chemical energy in organic molecules. Primary consumers (herbivores) obtain this energy by eating plants. Higher-level consumers, like a wolf, obtain energy by eating other animals. Carbon atoms, along with the stored energy, are transferred through the food chain and incorporated into the higher-level consumer's body.

Lab Topics

Scientific Method Lab 1

• Five Parts of the Scientific Method:
  1. Observation
  2. Hypothesis
  3. Experimentation/Observation
  4. Conclusion
  5. Scientific Theory
• Pill Bug (Roly Poly): A type of crustacean that lives on land.
• Biological Classification System: Understand the hierarchical categories from Kingdom to Species:
  1. Kingdom (Plantae, Animalia, Fungi, Protista, Eubacteria, Archaebacteria)
  2. Phylum
  3. Class
  4. Order
  5. Family
  6. Genus
  7. Species
• Binomial Nomenclature: Be able to explain the two-part naming system used to describe a particular organism (Genus species).

Microscopy Lab 2

• Key Terms:
  • Field of View: The 2-dimensional visual area seen through a microscope.
  • Depth of Field: The 3-dimensional "thickness" of the visual field that is in focus.
  • Plane of Focus: The 2-dimensional plane that is in sharp focus within the depth of field.
• Microscope Types:
  • Compound Microscope: Uses two magnification lenses (oculars and objectives). Know its components.
  • Dissecting / Stereoscopic Microscope: Uses one magnification lens (ocular) but provides two distinct viewing angles, offering a 3-D view. Know its components.
• Total Magnification: Ocular Magnification × Objective Magnification.
• Instruction: Be able to identify pictures or fixed slides of:
  • Amoeba (often appears irregular, like a "hand")
  • Euglena (contains chloroplasts, often elongated)
  • Volvox (spherical colony, like a "ball")
  • Elodea (plant cells, often rectangular)

Chemistry Lab 3

• Reagents and Their Uses:
  • Benedict's Reagent: Detects sugar.
  • Biuret Reagent: Detects protein.
  • Iodine Solution: Detects starch.
• Reaction Interpretation: Know what a negative reaction looks like compared to a positive reaction for each test.
• Monomers vs. Polymers: Understand the relationship.
• Four Types of Organic Molecules: (Refer to Chapter 2 for details) Proteins, Carbohydrates, Lipids, Nucleic Acids.

Cells & Diffusion Lab

• Distinguishing Cell Types:
  • Prokaryotes vs. Eukaryotes: Prokaryotes lack a true nucleus; eukaryotes possess a true nucleus.
  • Animal vs. Plant Cells: Plant cells typically have a cell wall and chloroplasts; animal cells do not.
• Cell Membrane Permeability: Understand how the cell membrane regulates molecule passage, often based on size (e.g., glucose is much smaller than starch).
• Types of Membrane Transport:
  • Simple Diffusion: Movement of small molecules from high concentration to low concentration, without energy use or transport proteins.
  • Facilitated Diffusion: Movement of molecules (often larger) from high concentration to low concentration, with the help of specific transport proteins, but without the use of energy.
  • Active Transport: Movement of molecules from low concentration to high concentration, requiring specific transport proteins and chemical energy (ATP) to pump molecules against their concentration gradient.
• Instruction: Know the function and appearance of most common cell organelles.
• Instruction: Understand osmosis thoroughly.

Key Terms and Concepts

Chapter 1 Terms

• Scientific method
• Control group
• Placebo
• Dependent variable
• Independent variable
• Hypothesis
• Observation
• Scientific theory
• Correlation
• Experiment

Chapter 2 Terms

• Matter
• Atom
• Proton
• Neutron
• Electron
• Molecule
• Organic
• Inorganic
• Cell
• Cell wall
• Cell membrane
• Carbohydrate
• Protein
• Lipid
• Amino acid
• Nucleic acid
• Phospholipid
• Hydrophilic
• Hydrophobic
• Monomer
• Polymer

Chapter 3 Terms

• Cell theory
• Prokaryote
• Eukaryote
• Cytoplasm
• Organelle
• Osmosis
• Mitochondria
• Chloroplast
• Golgi apparatus
• Endoplasmic reticulum (rough/smooth)
• Lysosome
• Nucleus
• Ribosome

Chapter 4 Terms

• Nutrients
• Macronutrients
• RUFT
• Essential amino acids
• Metabolism
• Enzyme
• Mineral
• Vitamin
• Catalyst

Chapter 5 Terms

• Fossil fuel
• Biofuel
• Energy
• Conservation of Energy
• Potential energy
• Photosynthesis
• Autotroph
• Heterotroph
• Photon
• Adenosine triphosphate (ATP)