BI 112 Exam Study Guide PDF

BI 112 Study Guide -- Exam \#1 (Textbook Chapters \#1 - 4) The best way to use this study guide to prepare for the exam is to study in two phases: Phase 1 (in the week leading up to the exam): for each question, review that topic in your course notes, chapter study guide and lecture slide deck....

BI 112 Study Guide -- Exam \#1 (Textbook Chapters \#1 - 4) The best way to use this study guide to prepare for the exam is to study in two phases: Phase 1 (in the week leading up to the exam): for each question, review that topic in your course notes, chapter study guide and lecture slide deck. Phase 2 (2-3 days before the exam): Write a short essay response to each question, supporting your answer with a drawing when appropriate. **Chapter 1: Introduction: Evolution and the Foundations of Biology** 1\. List and describe the five unifying themes of biology. - - - - - 2\. What is reductionism and why is it important in biology? How does systems biology complement this approach? **Reductionism- detailed understanding of part** and is important for **enabling discovery, aid target treatment and simplifies study**. **System biology- interaction and dynamics, together enhance biologist insight.** 3\. Diagram and describe the levels of biological organization (starting from atoms to organisms and from organisms to the biosphere). ### Atoms (smallest unit of matter) --------------------------------- Molecules organelles cells\` tissues organs organisms populations communities Ecosystems Biosphere (largest) 4\. Give a unique example of an emergent property in biology. **Flocking behavior in birds** 5\. Distinguish between eukaryotic and prokaryotic cells. **Eukaryotic- Nucleus+complex ( plants, animals)** **Prokaryotic- No nucleus+simpler and small (bacteria).** 6\. Define the following terms: DNA, genes, gene expression, genome, genomics, proteomics, and bioinformatics. **DNA**: Genetic material that carries information. **Genes**: DNA segments that code for proteins. **Gene Expression**: Process of turning genes into proteins. **Genome**: Complete set of an organism\'s genetic material. **Genomics**: Study of genomes and their functions. **Proteomics**: Study of proteins and their functions. **Bioinformatics**: Use of computers to analyze biological data. 7\. Describe how human activities have led to climate change. **Burning Fossil Fuels**: Releases CO₂ and greenhouse gases. **Deforestation**: Fewer trees mean more CO₂ in the air. **Agriculture**: Livestock and rice produce methane; fertilizers release nitrous oxide. **Industrial Processes**: Manufacturing emits greenhouse gases. **Waste Management**: Landfills create methane from waste. **Urbanization**: City growth increases energy use and emissions. 8\. Describe the classification system used by biologists today. In your description include the domains and the types of cells comprising each domain. Which kingdoms make up each domain? **Bacteria**: - - **Archaea**: - - **Eukarya**: - - 9\. List the key points of natural selection and define evolution. 1. 2. 3. 4. 5. 6. **Evolution- change in population over time through natural selection, leading to new species and adaptations.** 10\. Describe the scientific method. What is the difference between inductive and deductive reasoning? **Observation**: Identify a phenomenon. **Question**: Ask a question based on observations. **Hypothesis**: Propose a testable explanation. **Experiment**: Test the hypothesis through experiments. **Data Collection**: Gather and analyze data. **Conclusion**: Accept or reject the hypothesis. **Communication**: Share results with others. **Inductive Reasoning**: Specific observations → General conclusion (e.g., the sun rises every day, so it always will). **Deductive Reasoning**: General principle → Specific case (e.g., all humans are mortal; Socrates is human, so Socrates is mortal). 11\. Describe how scientific experiments are designed by giving an example of an experiment. In your description, correctly use and explain the following terms: observation, hypothesis, prediction, variables (dependent and independent), controlled (standardized) variables, control group, experimental or test group, and conclusion. 1. 2. 3. - - - **5. Control Group**: A group of plants that receives 6 hours of sunlight daily (baseline for comparison). **6. Experimental Group**: A group of plants that receives 12 hours of sunlight daily (the test group). 12\. What does the term theory mean to scientists? **theory** is a well-substantiated explanation of a natural phenomenon based on extensive evidence 1. 2. 3. 4. **Chapter 2: The Chemical Context of Life**. 1.Explain the importance of chemistry to the study of life. **Biological Molecules**: Explains the structure and function of proteins, carbohydrates, lipids, and nucleic acids. **Metabolism**: Helps understand how organisms obtain and use energy through chemical reactions. **Enzymes**: Describes how enzymes act as catalysts in biochemical reactions. **Cell Processes**: Fundamental to cellular functions like respiration and photosynthesis. **Environmental Impact**: Clarifies chemical interactions in ecosystems and pollution effects. **Medicine**: Aids in drug development and understanding diseases at the molecular level. **Chemistry = Life\'s Processes**: Molecules, metabolism, enzymes, cells, environment, and medicine. 2.What are the four elements that are most abundant in living organisms? **Carbon (C)**: The backbone of organic molecules; essential for life. **Hydrogen (H)**: Found in water and organic compounds; crucial for energy. **Oxygen (O)**: Vital for cellular respiration and found in water and organic molecules. **Nitrogen (N)**: A key component of amino acids and nucleic acids (DNA and RNA). **Carbon, Hydrogen, Oxygen, Nitrogen**: The building blocks of life 3.Know the symbols for the following elements: potassium, sodium, carbon, oxygen,hydrogen, calcium, nitrogen, sulfur, phosphorus, and chlorine. - - - - - - - - - - 4.Compare and contrast the terms elements, compounds, and atoms. - - - 5.Use a molecular formula to determine the number and types of atoms in that formula. Molecules formula: H2O - 6.Distinguish between electrons, neutrons and protons, atomic number and mass number. - - - - - 7.How can the atomic number and mass number of an atom be used to determine the number of protons, neutrons, and/or electrons? - - - 8.Define the term isotope and give an example of a biological application that uses radioactive isotopes. - - 9.What is an electron shell and how does it relate to an electron's potential energy? - - 10.What are valence electrons and how are they related to the bonding behavior of atoms? - - 11\. Describe, draw, and label a simplified model of an atom, such as carbon, hydrogen, nitrogen, oxygen, phosphorus, or sulfur given its atomic number and atomic mass. Atomic number Atomic mass ------------ --------------- ------------- Hydrogen 1 1 Carbon 6 12 Nitrogen 7 14 Oxygen 8 16 Phosphorus 15 31 Sulfur 16 32 12\. What is electronegativity and why is it important in determining the bonding behavior of an atom? - - - - 13\. Explain and draw an example of each of the four main types of bonds (ionic, nonpolar covalent, polar covalent, and hydrogen bonds). - [Ex:] Sodium Chloride ( NaCl).  - - Ex: Water (H2O) - Ex: Between water molecules  14.What is the relative strength of the four main bond types? - - - - - 15\. Compare and contrast cations and anions. **Feature** **Cations** **Anions** ----------------------- -------------------------------- --------------------------------- **Charge** Positive (+) Negative (−) **Formation** Formed by losing electrons Formed by gaining electrons **Example** Na⁺, Ca²⁺ Cl⁻, O²⁻ **Role in Compounds** Attracts anions in ionic bonds Attracts cations in ionic bonds 16\. Why are van der Waals interactions weak individually but powerful as a group? Feature Weak Individually Powerful as a Group ---------- ------------------------------ --------------------------------------- Strength Weak forces Strong overall effect Distance Very short range Can work larger distances Examples Dipole-dipole, London forces Stabilizing proteins, cell membranes Function Little impact alone Important for structure and stability 17\. Why do organisms need both strong and weak bonds? (Hint: Think about the advantages to possessing weak vs. strong bonds. For example, DNA contains weak hydrogen bonds between nitrogenous bases so that the molecule can be "unzipped" and replicated.) - 18\. Draw a simple chemical reaction, labeling the reactants and products. 19\. Diagram and explain the polarity of water molecules. -  20\. Explain the characteristics of water that result from hydrogen bonding including cohesion, adhesion, surface tension, specific heat, heat of vaporization, and density. **Cohesion**: Water molecules tend to stick to each other due to hydrogen bonding. This creates surface tension, allowing insects to walk on water and form droplets. **Adhesion**: Water molecules can also adhere to other surfaces. This property is crucial for capillary action, which helps water move through plant tissues. **Surface Tension**: The strong hydrogen bonds at the surface create a "skin" effect, making it resistant to being broken. This allows some objects, like small insects, to float on water. **Specific Heat**: Water has a high specific heat, meaning it can absorb a lot of heat without a significant increase in temperature. This helps stabilize environmental temperatures and maintain homeostasis in organisms. **Heat of Vaporization**: Water requires a lot of energy to evaporate due to its high heat of vaporization. This property is vital for cooling processes, such as sweating, which helps regulate body temperature. **Density**: Water is most dense at 4°C, and when it freezes, hydrogen bonding creates a lattice structure that makes ice less dense than liquid water. This allows ice to float, insulating aquatic ecosystems and protecting marine life in winter. 21.Why is water considered to be a good solvent? What substances might be considered solutes in an aqueous solution? - - 22.Distinguish between hydrophobic and hydrophilic interactions and give an example of each. - - 23.Explain pH. Define Acid and base.Give examples of some acids and bases. - - - 24.How are acids and bases capable of changing the hydrogen concentration of a solution? - - 25.Explain how buffers work using the example of the bicarbonate buffer system described in your text. - - - - - - **Chapter 3: Carbon and the Molecular Diversity of Life** 1\. What are organic compounds? - - 2\. Explain why carbon is such an important part of the structure of organic compounds. [**Tetravalence**:] Carbon has four valence electrons, allowing it to form four covalent bonds, leading to complex structures. **[Bonding Diversity]**: It can bond with various elements (H, O, N, S), creating a wide range of compounds. **[Chain and Ring Structures]**: Carbon can form long chains and rings, essential for macromolecules like proteins and nucleic acids. **[Stability]**: Strong carbon-carbon (C-C) and carbon-hydrogen (C-H) bonds provide structural integrity. **[Isomerism]**: Carbon can create isomers, contributing to the diversity and functionality of organic compounds. 3\. Compare and contrast the three different types of isomers. Type Definition Example -------------------- --------------------------------------------------------------------------- ---------------------------------------- Structural Isomers Differ in the connectivity of their atoms. Butane (n-butane vs. isobutane). Geometric Isomers Differ in spatial arrangement around a double bond or ring. Cis-2- butene vs.Trans-2-butene. Stereoisomers Same connectivity, different spatial arrangements (includes enantiomers). Lactic acid ( L-lactic vs. D- lactic). 4\. Name, recognize, and describe the basic structure of the seven major functional groups found in organic molecules and identify the chemical properties associated with each functional group ( figure 3.6). Functional group Chemical formula Structural formula Chemical properties ------------------ ------------------ -------------------- ------------------------------------------------------------------------------------------------------------ Hydroxyl OH Polar Methyl CH3 Nonpolar Carbonyl CO Polar Carboxyl COOH Charged, ionizes to release H+. Since this group release H+ ions into solution, they are considered acidic Amino NH2 Charged, accepts H+ ions so this group is basic Phosphate PO4 Charged, ionizes to release H+ ions so they are acidic Sulfhydryl SH Polar 5\. Distinguish between monomers and polymers. Make sure that you know which subunits compose each of the four biological macromolecules. - **Macromolecule** **Monomer** **Examples** ------------------- ----------------------- ------------------------------ Carbohydrates Monosaccharides Glucose, Fructose Proteins Amino acids Alanine, Glycine Nucleic Acids Nucleotides Adenine, Cytosine Lipids Fatty acid & Glycerol Triglycerides, Phospholipids 6\. Explain dehydration and hydrolysis reactions. Include in your explanation the role of water in these reactions. **Dehydration Reaction**: Joins monomers, releases water; forms polymers. **Hydrolysis Reaction**: Breaks down polymers, consumes water; forms monomers. 7\. What is the general formula for a carbohydrate? How do cells use carbohydrates? - Use of Carbohydrates cells includes : energy source, energy storage, structural support, Cell signaling, and building blocks. 8\. Differentiate between monosaccharides, disaccharides, and polysaccharides and describe their structures and functions. Type Structure Function Examples ----------------- --------------------------------------------------------- ------------------------------------------------ ---------------------------- Monosaccharides Single sugar units (3-7 carbon atoms). Primary energy source; building blocks. Glucose, Fructose Disaccharides Two monosaccharides linked by a glycosidic bond Quick energy source; transport form of sugars. Sucrose, Lactose Polysaccharides Long chains of monosaccharides (branched or unbranched) Energy storage and structural support. Starch glycogen, Cellulose 9\. Explain the differences between starch, glycogen, and cellulose. - - - 10\. Describe the structure and biological importance of lipids. **Fats**: Energy storage and insulation. **Phospholipids**: Cell membrane structure. **Steroids**: Hormonal regulation and signaling. **Waxes**: Protection and waterproofing. 11\. What makes lipids hydrophobic? - 12\. Explain the difference between a saturated fat and an unsaturated fat and how saturation affects their physical properties. **Saturation** affects the physical state: - - 13\. Describe the structure and function of phospholipids and steroids. **Phospholipids**: Form cell membranes; have hydrophilic heads and hydrophobic tails, creating a lipid bilayer. **Steroids**: Serve as hormones and stabilize cell membranes; characterized by a four-ring structure with various functional groups. 14\. Describe the structure of an amino acid. What is the significance of an amino acid's R group? ***-The structure of an amino acid consists of a central carbon, an amino group, a carboxyl group, a hydrogen atom, and a variable R group. The R group\'s significance lies in defining the amino acid\'s identity and properties, influencing protein structure, function, and interactions.*** 15\. How do the various R groups differ? (Figure 3.18) - 16\. What is the name of the bond that joins two amino acids? What kind of a bond is it? - 17\. What is meant by primary, secondary, tertiary, and quaternary protein structure? What types of bonds are involved in each level of structure? (Figure 3.22) - - - - 18\. Why is protein structure important? What role do chaperone proteins play in the process of folding? - - 19\. Explain what it means when we say that a protein is denatured. Identify some conditions under which denaturation can occur. - - 20\. List the different ways that cells can use various nucleotides. - 21\. What are the three main parts of a nucleotide? - 22\. Briefly describe the three-dimensional structure of DNA, making note of the kinds of bonds that hold its structure together. - 23\. To review macromolecules, identify the basic structural features of each of the four biological macromolecules, the monomers that make them up, and their related functions. - - - - - - - - - - - - - **Chapter 4: A Tour of the Cell** 1\. Identify the main concepts of cell theory. Which scientist is credited with the first observation of a cell? **All living organisms are composed of one or more cells.** **The cell is the basic unit of life.** **All cells arise from pre-existing cells.** - 2\. Compare and contrast the light microscope with the electron microscope. How else do cell biologists study cell structure and function? Light microscopes: visible light is passed through the specimen and then through glass lenses Electron microscopes: focuses a beam of electrons through the specimen or onto its surface. Another useful technique is Cell Fractionation: broken-up cells are placed in a tube that is spun in a centrifuge. 3\. What is a cell? - - 4\. What components are common to all cells? - - - - 5\. Compare and contrast prokaryotic cells and eukaryotic cells. Be thorough - make sure that you can distinguish between the two. **Prokaryotic Cells** **Eukaryotic Cells** ------------------------------- ------------------------------------------------ Lack of nucleus (no nucleus) Have nucleus Smaller (0.1-5.0 micrometers) Larger (10-100 micrometers) No membrane-bound organelles Have membrane-bound organelles Single DNA molecule Linear DNA Found in Bacteria and Archaea Found in plants, animals, fungi, and protists. 6\. Briefly describe the structure and function of the cell membrane (also called the plasma membrane). What is the cytoplasm of a cell and what is it made of? - - Cytoplasm is made of cytosol, organelles, and cytoskeleton is the gel-like substance within the cell membrane, excluding the nucleus in eukaryotic cells. 7\. Describe the structures and associated functions of the components of prokaryotic cells (keeping in mind that not all prokaryotic cells possess all possible structures). - - - - - - - - - - - - 8\. What are organelles? **Organelles are specialized structures within a cell that perform specific functions.** 9.Identify and describe the structure and function of the nucleus and the following components of the nucleus: nuclear envelope, nuclear pores, nuclear lamina, nucleolus, nucleoplasm, chromosomes, and chromatin. It might be helpful to draw this on a separate piece of paper, labeling the components as you go. (Figure 4.8) - - - - - - - - - - - - - - 10\. Identify and describe the structure and function of the following components of the endomembrane system: endoplasmic reticulum (smooth and rough), transport vesicles, Golgi apparatus, lysosomes, and vacuoles. ### **Endoplasmic Reticulum (ER)** - - - - - - ### **Transport Vesicles** - - ### **3. Golgi Apparatus** - - ### **4. Lysosomes** - - ### **5. Vacuoles** - - 11\. Identify and describe the structure and function of the mitochondria (including cristae, inner and outer membranes, matrix, and intermembrane space). (Figure 4.16) - - 12\. Explain why mitochondria are thought to have an endosymbiotic origin? What is the supporting evidence for this theory? - - - - - - These features support the theory that mitochondria originated from a symbiotic relationship. 13.Identify and describe the structure and essential function of chloroplasts. **Structure:** - - - - - **Function:** Chloroplasts perform photosynthesis, converting light energy into glucose and producing oxygen. They are essential for plant energy and oxygen supply on Earth. 14\. What is the role of peroxisomes within the cell? **Lipid Metabolism:** Break down fatty acids for energy. **Detoxification:** Convert harmful hydrogen peroxide into water and oxygen using catalase. **Biosynthesis:** Produce plasmalogens, important for cell membranes. **Regulation of ROS:** Manage reactive oxygen species to prevent cell damage. 15\. Describe the functions of the cytoskeleton. **Structural Support:** Maintains cell shape and integrity. **Cell Motility:** Enables cell movement and organelle transport. **Transport:** Moves materials within the cell. **Cell Division:** Organizes chromosomes during mitosis. **Cell Signaling:** Aids in responding to external signals. **Mechanical Resistance:** Provides stability against stress. 16.Compare the structure and function of microtubules (tubulin polymers), microfilaments (actin filaments), and intermediate filaments. **Microtubules** - - **Microfilaments** - - **Intermediate Filaments** - - 17\. Explain how the structure of cilia and flagella relates to their functions. **Structure:** - - **Function:** - - 18\. Name and give the functions of the cell junctions. (Figure 4.27) **Tight Junctions:** - **Adherens Junctions:** - **Desmosomes:** - **Gap Junctions:** - 19\. Describe the structure and function of plant cell walls. What other eukaryotic cells contain cell walls? **Structure:** - - - - - **Function:** - - - - Plant cell walls provide structure and protection, while other eukaryotic cells (fungi and algae) have walls made of different materials. 20\. Distinguish between the components of the extracellular matrix (ECM). -