Chapter 1 - 3 Multiple choice easy made up by chatgpt_now for quizgecko.docx

What is the primary component of cell membranes? a) Nucleic acids b) Proteins c) Carbohydrates d) Phospholipids e) Cholesterol Which process describes the synthesis of RNA from a DNA template? a) Replication b) Transcription c) Translation d) Reverse transcription e) Polymerization What structu...

What is the primary component of cell membranes? a) Nucleic acids b) Proteins c) Carbohydrates d) Phospholipids e) Cholesterol Which process describes the synthesis of RNA from a DNA template? a) Replication b) Transcription c) Translation d) Reverse transcription e) Polymerization What structure is responsible for protein synthesis in the cell? a) Golgi apparatus b) Endoplasmic reticulum c) Ribosome d) Mitochondrion e) Nucleus The theory that describes the origin of eukaryotic cells from prokaryotic organisms is known as: a) Symbiotic theory b) Evolutionary theory c) Endosymbiotic theory d) Prokaryotic theory e) Cellular theory Which organelle is primarily involved in the detoxification of drugs and poisons in liver cells? a) Lysosome b) Peroxisome c) Mitochondrion d) Smooth endoplasmic reticulum e) Rough endoplasmic reticulum Which type of protein structure is characterized by the sequence of amino acids? a) Primary structure b) Secondary structure c) Tertiary structure d) Quaternary structure e) Alpha-helix structure Which process is essential for the segregation of chromosomes during cell division? a) Transcription b) Translation c) Mitosis d) Meiosis e) Cytokinesis What molecule serves as the primary energy currency in cells? a) Glucose b) ATP (Adenosine triphosphate) c) NADH (Nicotinamide adenine dinucleotide) d) FADH2 (Flavin adenine dinucleotide) e) GTP (Guanosine triphosphate) Which process in eukaryotic gene expression allows for a single gene to code for multiple proteins? a) Gene duplication b) Transcriptional regulation c) Post-transcriptional modification d) Alternative splicing e) Repetitive DNA sequencing In DNA replication, which enzyme is responsible for unwinding the double helix? a) DNA polymerase b) Helicase c) Ligase d) Primase e) Topoisomerase Chapter 1: Introduction to Cells Which statement best describes a fundamental property of cells? a) Cells can only originate from existing cells. b) All cells have a nucleus. c) Cells do not maintain a distinct internal environment. d) Cells are generally of the same size and shape. e) All cells are visible to the naked eye. What is considered the basic unit of life? a) Organ b) Cell c) Tissue d) Molecule e) Atom The theory that all living things are composed of cells is known as the: a) Cellular theory. b) Organismal theory. c) Atomic theory. d) Evolutionary theory. e) Genetic theory. Which type of microscope would be best for studying the detailed structure of the surface of a cell? a) Light microscope b) Transmission electron microscope c) Scanning electron microscope d) Fluorescence microscope e) Phase-contrast microscope What is the primary role of DNA in cells? a) Energy production b) Cell movement c) Genetic information storage d) Catalyzing biochemical reactions e) Transport of nutrients Which of the following is a characteristic of prokaryotic cells? a) They contain membrane-bound organelles. b) They lack a defined nucleus. c) They are generally larger than eukaryotic cells. d) They have a complex internal structure. e) They are exclusively multicellular. In the context of cell theory, which statement is accurate? a) Cells are the smallest entities considered to be alive. b) All cells are similar in terms of metabolism. c) Cells arise spontaneously under certain conditions. d) All cells come from pre-existing non-cellular structures. e) Cellular organization is not essential for life processes. Which organelle is commonly referred to as the 'powerhouse of the cell'? a) Nucleus b) Endoplasmic reticulum c) Golgi apparatus d) Mitochondrion e) Lysosome Cellular membranes are primarily composed of: a) Proteins and nucleic acids. b) Carbohydrates and lipids. c) Phospholipids and proteins. d) Monosaccharides and polysaccharides. e) Amino acids and fatty acids. The fluid mosaic model describes the cell membrane as: a) A rigid structure with uniform composition. b) A dynamic structure with a mixture of lipids and proteins. c) An impermeable barrier to substances. d) Composed solely of proteins. e) Lacking in fluidity and flexibility. Chapter 1: Introduction to Cells (Continued) Which organelles are involved in the process of protein synthesis? a) Mitochondria and lysosomes b) Ribosomes and endoplasmic reticulum c) Golgi apparatus and peroxisomes d) Nucleus and vacuoles e) Chloroplasts and mitochondria What is the main function of the cytoskeleton in a cell? a) Energy production b) Storage of genetic information c) Structural support and movement d) Protein synthesis e) Digestion of cellular waste In which part of a eukaryotic cell is the DNA found? a) Cytoplasm b) Mitochondria c) Nucleus d) Endoplasmic reticulum e) Ribosomes What type of cells lack a membrane-bound nucleus? a) Eukaryotic cells b) Prokaryotic cells c) Animal cells d) Plant cells e) Fungal cells Which statement best describes viruses? a) Viruses are considered living organisms. b) Viruses possess both DNA and RNA. c) Viruses can replicate independently of a host cell. d) Viruses are cellular entities. e) Viruses require a host cell to replicate. The endosymbiotic theory is primarily associated with the origin of: a) Nuclei b) Mitochondria and chloroplasts c) Endoplasmic reticulum d) Ribosomes e) Golgi apparatus What is the primary barrier that separates the interior of the cell from the external environment? a) Cell wall b) Plasma membrane c) Cytoplasm d) Nucleus e) Extracellular matrix Which cell component is primarily responsible for breaking down worn-out cellular structures? a) Lysosomes b) Peroxisomes c) Ribosomes d) Mitochondria e) Endoplasmic reticulum Which process involves the movement of substances across the cell membrane against a concentration gradient? a) Passive transport b) Osmosis c) Diffusion d) Active transport e) Facilitated diffusion Photosynthesis primarily occurs in which type of cell? a) Animal cells b) Bacterial cells c) Plant cells d) Fungal cells e) Protozoan cells Chapter 1: Introduction to Cells Which cellular structure is involved in the modification, sorting, and packaging of proteins? a) Golgi apparatus b) Lysosome c) Mitochondrion d) Nucleus e) Ribosome What is the primary role of the smooth endoplasmic reticulum? a) Protein synthesis b) Lipid synthesis and detoxification c) Energy production d) DNA replication e) Intracellular transport Which component is responsible for the selective permeability of the cell membrane? a) Carbohydrates b) Cholesterol c) Phospholipids d) Proteins e) Nucleic acids Cellular respiration, a process that generates ATP, primarily takes place in the: a) Nucleus b) Cytoplasm c) Endoplasmic reticulum d) Mitochondria e) Golgi apparatus The process by which a cell engulfs a solid particle is known as: a) Exocytosis b) Endocytosis c) Phagocytosis d) Pinocytosis e) Osmosis Which type of cell junctions allow for direct communication between adjacent animal cells? a) Tight junctions b) Desmosomes c) Gap junctions d) Adherens junctions e) Hemidesmosomes Which molecule serves as the 'genetic blueprint' in living organisms? a) RNA b) DNA c) ATP d) Protein e) Lipid In a cell, ribosomal RNA (rRNA) is primarily found in the: a) Nucleus b) Cytoplasm c) Ribosomes d) Mitochondria e) Endoplasmic reticulum Which process describes the movement of water across a semi-permeable membrane? a) Osmosis b) Diffusion c) Active transport d) Facilitated diffusion e) Filtration The cell theory states that: a) Only multicellular organisms are composed of cells. b) Cells can arise spontaneously. c) All living things are made of cells and cell products. d) Cells are not the basic unit of life. e) Cells do not contribute to the structure and function of living things. Chapter 2: Chemical Components of Cells Which element is a primary component of all organic molecules? a) Oxygen b) Carbon c) Nitrogen d) Hydrogen e) Phosphorus What type of bond is formed when two atoms share electrons? a) Ionic bond b) Covalent bond c) Hydrogen bond d) Van der Waals bond e) Metallic bond What property of water makes it an excellent solvent in biological systems? a) Its high boiling point b) Its ability to form hydrogen bonds c) Its nonpolar nature d) Its low specific heat e) Its gaseous state at room temperature Which molecule is the primary source of energy in cellular metabolism? a) Glucose b) ATP (Adenosine triphosphate) c) Fatty acid d) Amino acid e) Glycerol Amino acids are the building blocks of: a) Carbohydrates b) Nucleic acids c) Proteins d) Lipids e) Vitamins Which type of lipid is a major component of cell membranes? a) Steroids b) Triglycerides c) Phospholipids d) Waxes e) Fatty acids Nucleotides are composed of: a) A sugar, a nitrogenous base, and a phosphate group b) Amino acids and a phosphate group c) Fatty acids and glycerol d) A sugar and a nitrogenous base e) A phosphate group and a fatty acid Enzymes, which catalyze chemical reactions in the cell, are typically: a) Lipids b) Carbohydrates c) Nucleic acids d) Proteins e) Vitamins What type of reaction involves the removal of water to form a bond between two molecules? a) Hydrolysis reaction b) Dehydration synthesis c) Oxidation reaction d) Reduction reaction e) Isomerization reaction Which organic molecule is primarily used for storing genetic information? a) RNA b) DNA c) ATP d) Protein e) Carbohydrate Which property of carbon allows it to form a wide variety of structures, including chains and rings? a) Its ability to form four covalent bonds b) Its electronegativity c) Its ionic bonding capability d) Its gaseous state at room temperature e) Its radioactivity What is the primary function of carbohydrates in cells? a) Energy storage and structural support b) Catalyzing chemical reactions c) Storing genetic information d) Signaling between cells e) Transporting oxygen What type of bond is formed between amino acids in a protein? a) Glycosidic bond b) Peptide bond c) Hydrogen bond d) Phosphodiester bond e) Ionic bond Which is not a nitrogenous base found in DNA? a) Adenine b) Guanine c) Cytosine d) Uracil e) Thymine Cholesterol, a type of lipid, plays an important role in: a) Cell membrane fluidity b) Energy storage c) Protein synthesis d) DNA replication e) Enzyme activation The primary structure of a protein is determined by: a) Hydrogen bonding between amino acids b) The sequence of amino acids c) The folding into alpha helices and beta sheets d) The interaction with other protein molecules e) The presence of disulfide bonds Which type of macromolecule is primarily responsible for catalyzing biochemical reactions in the cell? a) Proteins b) Carbohydrates c) Lipids d) Nucleic acids e) Vitamins Which structure is characteristic of a nucleotide? a) A fatty acid chain b) An amino acid sequence c) A sugar, a nitrogenous base, and a phosphate group d) A glycerol backbone and three fatty acids e) A ribose sugar and a nitrogenous base What is the role of ribosomal RNA (rRNA) in the cell? a) Storing genetic information b) Transporting amino acids c) Catalyzing peptide bond formation d) Acting as a primary energy carrier e) Providing structural support to the cell membrane Which cellular process primarily involves carbohydrates? a) DNA replication b) Protein synthesis c) Cellular respiration d) Signal transduction e) Cell wall synthesis Chapter 2: Chemical Components Saturated fatty acids are characterized by: a) Double bonds between carbon atoms. b) A straight chain structure. c) Being liquid at room temperature. d) The presence of a phosphate group. e) An amino group at one end. Which component is not found in nucleotides? a) Ribose sugar b) Nitrogenous base c) Phosphate group d) Fatty acid e) Purine or pyrimidine base What is the primary function of enzymes in biological reactions? a) To store energy b) To provide structural support c) To speed up chemical reactions d) To transport molecules across membranes e) To serve as genetic material The alpha-helix and beta-sheet are examples of which level of protein structure? a) Primary structure b) Secondary structure c) Tertiary structure d) Quaternary structure e) Supersecondary structure Which type of RNA carries the genetic code from DNA to the ribosome? a) Messenger RNA (mRNA) b) Transfer RNA (tRNA) c) Ribosomal RNA (rRNA) d) MicroRNA (miRNA) e) Small nuclear RNA (snRNA) What is the main function of the polysaccharide cellulose in plants? a) Energy storage b) Structural support c) Signaling d) Catalysis e) Genetic information storage In a water molecule, the oxygen and hydrogen atoms are held together by: a) Ionic bonds b) Covalent bonds c) Hydrogen bonds d) Van der Waals interactions e) Metallic bonds Which process describes the synthesis of a new protein molecule? a) Transcription b) Translation c) Replication d) Metabolism e) Glycolysis Phospholipids are important components of: a) The cell nucleus b) Ribosomes c) The cell membrane d) Mitochondria e) Chloroplasts What is the role of cholesterol in the cell membrane? a) Acts as a transporter for ions b) Serves as the primary structural component c) Provides rigidity to the membrane d) Modulates membrane fluidity e) Functions as a signaling molecul Chapter 2: Chemical Components of Cells What type of molecule is primarily responsible for the storage and expression of genetic information? a) Proteins b) Lipids c) Carbohydrates d) Nucleic acids e) Steroids Which type of chemical bond is crucial for maintaining the secondary structure of proteins? a) Peptide bonds b) Glycosidic bonds c) Hydrogen bonds d) Disulfide bridges e) Ionic bonds Steroids are a type of lipid characterized by: a) A four-ring structure b) Long fatty acid chains c) Phosphate groups d) Amino groups e) Glycerol backbone What is the primary role of RNA molecules in cells? a) Energy storage b) Structural support c) Catalyzing biochemical reactions d) Playing a role in gene expression and protein synthesis e) Providing a barrier to the external environment Which molecule is not typically found in the plasma membrane of a cell? a) Phospholipid b) Cholesterol c) Glycoprotein d) Ribonucleic acid (RNA) e) Integral protein In what form are carbohydrates typically stored in animal cells? a) Starch b) Cellulose c) Glycogen d) Chitin e) Sucrose The primary structure of a protein is determined by: a) Hydrogen bonding between amino acids b) The sequence of amino acids c) The overall 3D shape of the molecule d) Interactions between side chains (R groups) e) The presence of disulfide bridges Enzymes are biological catalysts that: a) Decrease the activation energy of reactions b) Increase the activation energy of reactions c) Consume energy to initiate reactions d) Alter the equilibrium of reactions e) Are consumed during the reaction Water's high specific heat is mainly a consequence of the: a) Mobility of water molecules b) Large size of water molecules c) Nonpolar nature of water d) Hydrogen bonding between water molecules e) High density of water An example of a monosaccharide is: a) Starch b) Cellulose c) Glycogen d) Glucose e) Sucrose The formation of a dipeptide from two amino acids involves: a) A hydrolysis reaction b) The formation of a hydrogen bond c) A dehydration synthesis reaction d) The breaking of a peptide bond e) An ionic bond formation Lipids differ from other macromolecules because they: a) Are predominantly hydrophilic b) Are made of amino acids c) Are not polymers d) Contain only carbon and hydrogen e) Are made of nucleotides A nucleoside differs from a nucleotide in that the nucleoside lacks: a) A nitrogenous base b) A phosphate group c) A sugar molecule d) A hydroxyl group e) Carbon atoms The tertiary structure of a protein is important because it: a) Determines the protein's specificity and function b) Is the simplest form of protein structure c) Consists only of alpha helices or beta sheets d) Determines the sequence of amino acids e) Is maintained solely by peptide bonds Which biological molecule is composed of amino acid subunits? a) Protein b) Nucleic acid c) Lipid d) Carbohydrate e) Vitamin The amphipathic nature of phospholipids refers to: a) Their ability to dissolve in water and oil equally b) Having both hydrophilic and hydrophobic regions c) The presence of both positive and negative charges d) The ability to form micelles and bilayers e) Their role in energy storage Which process is not directly involved in protein synthesis? a) Transcription b) Translation c) Replication d) Ribosome assembly e) tRNA charging What is the role of ribosomal RNA (rRNA) in the cell? a) Storing genetic information b) Transporting amino acids c) Catalyzing peptide bond formation d) Acting as a primary energy carrier e) Providing structural support to the cell membrane Which cellular process primarily involves carbohydrates? a) DNA replication b) Protein synthesis c) Cellular respiration d) Signal transduction e) Cell wall synthesis The cell theory states that: a) Only multicellular organisms are composed of cells. b) Cells can arise spontaneously. c) All living things are made of cells and cell products. d) Cells are not the basic unit of life. e) Cells do not contribute to the structure and function of living things Chapter 3: Energy, Catalysis, and Biosynthesis What is the primary form of energy used by cells? a) Glucose b) ATP (Adenosine triphosphate) c) Fatty acids d) GTP (Guanosine triphosphate) e) NADH (Nicotinamide adenine dinucleotide) An enzyme functions to: a) Store genetic information b) Catalyze biochemical reactions c) Provide structural support d) Transport substances across membranes e) Store energy Photosynthesis primarily occurs in which organelle? a) Mitochondria b) Chloroplast c) Nucleus d) Ribosome e) Endoplasmic reticulum What is the main role of chlorophyll in photosynthesis? a) Absorbing light energy b) Producing oxygen c) Synthesizing glucose d) Breaking down carbon dioxide e) Storing energy What molecule is the final electron acceptor in the electron transport chain of aerobic respiration? a) Oxygen b) Carbon dioxide c) ATP d) Glucose e) Water Which process converts glucose into pyruvate with the production of ATP? a) Photosynthesis b) Krebs cycle c) Glycolysis d) Electron transport chain e) Fermentation What is the primary function of the Krebs cycle? a) Producing oxygen b) Generating ATP c) Synthesizing proteins d) Breaking down glucose e) Releasing carbon dioxide In which part of the cell does glycolysis occur? a) Nucleus b) Mitochondria c) Cytoplasm d) Chloroplast e) Endoplasmic reticulum The process of converting light energy into chemical energy during photosynthesis takes place in: a) Thylakoids b) Stroma c) Granum d) Cristae e) Matrix Anaerobic respiration differs from aerobic respiration in that it: a) Uses oxygen as the final electron acceptor b) Occurs in the presence of oxygen c) Does not use an electron transport chain d) Produces more ATP than aerobic respiration e) Does not require oxygen Which molecule acts as the primary electron donor in photosynthesis? a) Carbon dioxide b) Water c) Oxygen d) Glucose e) ATP ATP synthase plays a critical role in cellular respiration by: a) Synthesizing ATP b) Breaking down glucose c) Transferring electrons d) Producing oxygen e) Absorbing light energy The process of fixing carbon dioxide into organic compounds is known as: a) Glycolysis b) Fermentation c) Calvin cycle d) Krebs cycle e) Photolysis Which molecule is used by cells as a cofactor for enzymes? a) Glucose b) DNA c) RNA d) ATP e) NAD+ (Nicotinamide adenine dinucleotide) The term 'metabolism' refers to: a) The synthesis of macromolecules b) The breakdown of nutrients c) All chemical reactions in a cell d) Only energy-producing reactions e) Only energy-consuming reactions Chapter 3: Energy, Catalysis, and Biosynthesis What is the primary role of NADH in cellular respiration? a) Storing genetic information b) Providing structure to the cell membrane c) Transporting electrons in the electron transport chain d) Acting as an enzyme in glycolysis e) Directly synthesizing ATP Which molecule is a common energy currency in the cell? a) Glucose b) ATP (Adenosine triphosphate) c) Fatty acid d) Amino acid e) Glycerol During photosynthesis, the oxygen released comes from: a) Carbon dioxide b) Water c) Glucose d) ATP e) NADPH In the absence of oxygen, some cells can obtain energy by: a) Glycolysis followed by aerobic respiration b) Glycolysis followed by fermentation c) The Krebs cycle only d) The electron transport chain only e) Photophosphorylation Which compound is not involved in the Calvin cycle? a) Ribulose-1,5-bisphosphate b) 3-phosphoglycerate c) Glucose-6-phosphate d) Glycerate-3-phosphate e) Glyceraldehyde-3-phosphate The process of oxidative phosphorylation is associated with: a) The synthesis of ATP using energy from redox reactions b) The direct transfer of phosphate to ADP from a substrate c) The breakdown of glucose to pyruvate d) The synthesis of proteins from amino acids e) The splitting of water during photosynthesis Which organelle is the site of aerobic respiration in eukaryotic cells? a) Nucleus b) Mitochondria c) Chloroplast d) Golgi apparatus e) Endoplasmic reticulum Anabolism refers to: a) The breakdown of complex molecules into simpler ones b) The consumption of energy to build complex molecules c) The release of energy by breaking down complex molecules d) The process of photosynthesis e) The process of cellular respiration Which molecule serves as a primary electron donor in photosynthesis? a) Carbon dioxide b) Water c) Glucose d) Oxygen e) ATP What is the significance of enzyme catalysts in biological systems? a) They are consumed in chemical reactions b) They decrease the activation energy of reactions c) They change the equilibrium of reactions d) They increase the activation energy of reactions e) They prevent reactions from occurring Catabolic pathways: a) Are involved in the synthesis of cellular components b) Typically consume energy c) Break down complex molecules into simpler ones d) Only occur in the absence of oxygen e) Are not involved in energy production The energy released by the hydrolysis of ATP is used for: a) Storing genetic information b) Building complex molecules c) Catalyzing biochemical reactions d) Transporting substances across cell membranes e) All of the above In cellular respiration, the final electron acceptor in the electron transport chain is: a) Oxygen b) Water c) Glucose d) ATP e) Carbon dioxide Which process is not part of aerobic respiration? a) Glycolysis b) Krebs cycle c) Electron transport chain d) Lactic acid fermentation e) Oxidative phosphorylation What role do vitamins play in the cell? a) Structural components of membranes b) Storage of genetic information c) Coenzymes or precursors for coenzymes d) Primary energy source e) Catalysts for DNA replication Chapter 3: Energy, Catalysis, and Biosynthesis Which enzyme is responsible for carbon fixation in the Calvin cycle? a) Rubisco (Ribulose-1,5-bisphosphate carboxylase/oxygenase) b) ATP synthase c) Hexokinase d) Cytochrome c oxidase e) PEP carboxylase The principle that energy cannot be created or destroyed, but can only be transformed from one form to another, is known as: a) The first law of thermodynamics b) The second law of thermodynamics c) The law of conservation of mass d) The law of conservation of energy e) The law of entropy In photosynthesis, light energy is converted into: a) Kinetic energy b) Thermal energy c) Mechanical energy d) Chemical energy e) Nuclear energy Which molecule acts as a primary carrier of electrons during photosynthesis? a) NADP+ (Nicotinamide adenine dinucleotide phosphate) b) ATP c) FAD (Flavin adenine dinucleotide) d) NAD+ (Nicotinamide adenine dinucleotide) e) Coenzyme Q What is the primary function of the electron transport chain in mitochondria? a) Synthesizing glucose b) Producing ATP c) Breaking down fatty acids d) Converting oxygen to carbon dioxide e) Transporting proteins The conversion of glucose to two molecules of pyruvate during glycolysis results in the net gain of: a) 2 ATP and 2 NADH b) 4 ATP and 2 NADH c) 2 ATP and 4 NADH d) 4 ATP and 4 NADH e) 6 ATP and 2 NADH Which compound is a byproduct of anaerobic respiration in muscle cells? a) Ethanol b) Lactic acid c) Acetic acid d) Carbon dioxide e) Oxygen What is the role of light in photosynthesis? a) To produce ATP and NADPH b) To break down carbon dioxide c) To synthesize water from oxygen d) To provide energy for the Calvin cycle e) To generate heat energy Substrate-level phosphorylation occurs in: a) Glycolysis b) Krebs cycle c) Electron transport chain d) Both a and b e) Both b and c Which process is primarily responsible for the oxygenation of Earth's atmosphere? a) Cellular respiration b) Photosynthesis c) Fermentation d) Nitrogen fixation e) Fossil fuel combustion The main purpose of fermentation is to: a) Produce ATP in the absence of oxygen b) Regenerate NAD+ for glycolysis c) Break down glucose completely d) Produce lactic acid or ethanol e) Generate carbon dioxide In the Calvin cycle, 3-phosphoglycerate is converted into: a) Ribulose-1,5-bisphosphate b) Glycerate-3-phosphate c) Glyceraldehyde-3-phosphate d) Glucose-6-phosphate e) Fructose-1,6-bisphosphate What is the primary function of ATP in cellular processes? a) To serve as a genetic material b) To provide energy for cellular activities c) To act as a structural component of membranes d) To catalyze biochemical reactions e) To store long-term energy Enzyme specificity refers to the: a) Ability of an enzyme to catalyze multiple reactions b) Speed at which an enzyme catalyzes a reaction c) Ability of an enzyme to bind to a particular substrate d) Amount of energy required to activate an enzyme e) Location of an enzyme within a cell What is the relationship between an enzyme and its substrate? a) The substrate binds to the enzyme's active site b) The enzyme degrades the substrate into smaller molecules c) The enzyme provides energy to the substrate d) The substrate inhibits the action of the enzyme e) The enzyme and substrate repel each other Which statement accurately describes the second law of thermodynamics? a) Energy can be transformed from one form to another b) Energy cannot be created or destroyed c) In every energy transfer, some energy becomes unavailable to do work d) Energy transfers are always 100% efficient e) Total energy in a closed system remains constant Catabolism and anabolism are: a) Unrelated metabolic processes b) The same type of metabolic process c) Respectively, energy-releasing and energy-consuming processes d) Both energy-consuming processes e) Both processes that occur only in prokaryotes What is the role of an enzyme's active site? a) To store energy b) To bind the substrate and lower the activation energy c) To synthesize ATP d) To provide structural support e) To transport molecules An exergonic reaction is one that: a) Requires an input of energy b) Releases energy c) Is in equilibrium d) Occurs spontaneously without enzymes e) Involves the synthesis of complex molecules The ultimate source of energy for most life on Earth is: a) Oxygen b) Glucose c) The sun d) ATP e) Water Chapter 3: Energy, Catalysis, and Biosynthesis What is a cofactor? a) A protein that assists in DNA replication b) A carbohydrate that provides energy for cell processes c) A non-protein chemical compound that assists enzyme function d) A lipid that forms part of the cell membrane e) A type of RNA involved in protein synthesis Activation energy is: a) The energy required to start a reaction b) The energy released during a reaction c) The energy stored in ATP d) The energy absorbed from sunlight in photosynthesis e) The energy required to stop a reaction Which molecule is produced during the light reactions of photosynthesis and used in the Calvin cycle? a) Carbon dioxide b) Oxygen c) ATP d) Glucose e) Water What is the primary purpose of the light reactions in photosynthesis? a) To produce oxygen b) To convert ATP to ADP c) To synthesize glucose d) To generate ATP and NADPH e) To absorb carbon dioxide In the context of metabolism, anabolic pathways: a) Break down complex molecules into simpler ones b) Typically release energy c) Involve the synthesis of complex molecules d) Do not require energy input e) Are only active in prokaryotic cells Which term describes the sum of all chemical reactions within a living organism? a) Catabolism b) Anabolism c) Metabolism d) Catalysis e) Bioenergetics The process by which green plants and some other organisms use sunlight to synthesize foods is called: a) Fermentation b) Cellular respiration c) Photosynthesis d) Glycolysis e) Oxidative phosphorylation Which compound is the principal electron donor in redox reactions? a) Water b) Oxygen c) NADH d) ATP e) Carbon dioxide In which cellular location does the Calvin cycle take place? a) Mitochondrial matrix b) Cytoplasm c) Chloroplast stroma d) Thylakoid membrane e) Endoplasmic reticulum What is the primary function of the electron transport chain in chloroplasts? a) Synthesizing glucose b) Producing ATP c) Breaking down fatty acids d) Converting oxygen to carbon dioxide e) Transporting proteins