MCAT Basics (from MedSchoolCoach)

Mastering the concept of sociological groups can unlock a deeper understanding of how we interact and influence each other. On top of that, social interactions and group dynamics form the backbone of the Psych/Soc section of the MCAT, so mastering this topic is key to a good score.  In this episode, host Sam Smith breaks down the essential topic of sociological groups. You’ll gain a comprehensive understanding of the different types of groups, the dynamics within organizations, bureaucracy, and social networks, and key concepts like groupthink, group polarization, and social loafing. We also explore how these concepts apply to real-world examples, from business partnerships to historical events like the Salem witch trials.  Visit medschoolcoach.com for more help with the MCAT. Jump into the conversation: 00:00 Intro 02:09 Types of social groups and social networks 08:06 Organizations and bureaucracy 10:17 Normative organizations 16:16 Group interactions and dynamics 20:08 Difference between group think and group polarization 27:57 Deindividuation, aka the ‘mob mentality’ 31:57 Cultural groups and assimilation 34:22 MCAT Advice of the Day

In this episode, we explore key topics in genetics, including how sex-linked and autosomal traits are inherited. We'll break down inheritance patterns using real-world examples, like X-linked recessive diseases, and walk through Punnett square problems to show how these traits are passed down. We also cover the regulation of gene expression, focusing on epigenetic changes such as DNA methylation and how genetic imprinting impacts which genes are expressed. You'll gain insight into transcriptional and post-transcriptional control mechanisms in prokaryotes and eukaryotes, along with the processes of DNA repair that maintain genetic stability. Finally, we discuss important genetic lab techniques, such as PCR, blotting methods, and fluorescence in situ hybridization (FISH), and how they are used in gene analysis and diagnostics. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:49)  Inheritance patterns (04:47) Solving X-linked inheritance problems using color blindness (06:37) Overview of autosomal dominant and recessive traits (08:08) Monohybrid and dihybrid crosses (10:40) How epigenetic changes affect gene expression (18:46) Transcriptional and translational control in prokaryotic operons (23:03) Enhancers, silencers, and chromatin remodeling (27:23) Post-transcriptional modifications (31:52) DNA repair mechanisms (40:14) Polymerase Chain Reaction (44:06) What different blotting techniques are used for (49:28) The FISH technique (52:01) MCAT Advice of the Day

In this episode, we cover the foundational concepts of genetics, focusing on chromosomes, mitosis, meiosis, and inheritance patterns—important topics for the MCAT Bio/Biochem section. We’ll discuss how Gregor Mendel’s laws of segregation, independent assortment, and dominance influence inheritance and how Charles Darwin’s theory of natural selection relates to modern genetics. The episode includes an overview of chromosome structure, the differences between X and Y chromosomes, and the effects of chromosomal mutations like deletions, duplications, and translocations. Mitosis and meiosis are also explained, with an emphasis on their roles in cell division and genetic diversity. Additionally, we explore genetic concepts such as codominance, incomplete dominance, genetic leakage, and how factors like penetrance and expressivity influence gene expression. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Introduction to Genetics and Chromosomes (01:41) Background on genetics: Key figures and their contributions (Mendel, Darwin) (03:37) Mendel’s Laws: Segregation, independent assortment, and dominance (05:50) Charles Darwin: Evolution and natural selection in genetics (09:43) Chromosomes and DNA: Discovery and role in inheritance (11:29) Chromosome Numbers and Structure: Ploidy, chromatids, and human chromosomes (14:06) X and Y Chromosomes: Sex determination and sex-linked traits (18:34) Chromosomal Mutations: Duplication, deletion, inversion, translocation (22:00) Mitosis: Stages and the production of identical daughter cells (28:16) Meiosis: Gamete formation and genetic diversity (32:40) Centrosome, Centromere, and Centriole: Roles in cell division (33:50) Genes and Phenotypes: Alleles, genotypes, and their effect on traits (38:28) Dominant and Recessive Alleles: How traits are determined (40:37) Genetic Leakage, Penetrance, and Expressivity: Gene flow, expression likelihood, and variability (42:47) MCAT Advice of the Day

In this episode, we explore enzyme kinetics and inhibition, key concepts for the MCAT Bio/Biochem section. We’ll cover how enzymes accelerate biological reactions by lowering activation energy and introduce two models for enzyme-substrate interaction: the lock-and-key model and the induced fit model. You'll learn how to apply the Michaelis-Menten equation, focusing on factors like Km and Vmax to understand enzyme efficiency and substrate binding. We’ll also break down the different types of enzyme inhibition—competitive, non-competitive, and uncompetitive—and their effects on enzyme activity. Finally, we discuss the six major types of enzymes and their roles in biological processes, with examples like ligases, isomerases, and hydrolases. Visit MedSchoolCoach.com for more help with the MCAT.   Jump into the conversation: (00:00) Introduction to enzyme kinetics and inhibition (01:58) Definition of enzymes and their role (03:50) Enzyme models: lock and key vs. induced fit (06:28) Michaelis-Menten Equation (10:53) Association and dissociation constants (12:34) Kcat and catalytic efficiency (14:43) Assumptions of Michaelis-Menten (18:23) Lineweaver-Burk Plot: linearized Michaelis-Menten Equation (21:09) Enzyme inhibition: reversible vs. irreversible (22:14) Competitive inhibition: Km and Vmax (24:46) Non-competitive inhibition: Effects on Km and Vmax (27:20) Irreversible inhibition (29:13) Allosteric inhibition (31:26) Homotropic and feedback inhibition (37:40) Common biological enzymes: dehydrogenase, synthetase, and kinase (43:44) MCAT Advice of the Day

In this episode, we’ll learn the intricate world of biomolecule structure, naming, and function. We'll explore the structural nuances between glucose and fructose and unravel the complexities of glycosidic linkages in sucrose. We'll also examine the vital roles of fatty acids, the composition of triglycerides and phospholipids, and their impact on cell membrane architecture and fluidity. Plus, we discuss cholesterol's bidirectional regulation of membrane stability and the contrasting roles of LDL and HDL in cardiovascular health. We’ll dive into the essential structures and functions of steroids and nucleotides, as well as the fundamentals of DNA and RNA structure and the importance of ATP. We'll also look at the unique properties of sphingolipids, glycerophospholipids, and signaling molecules like eicosanoids. So, tune in as we break down these critical biomolecules that form the foundation of life and are essential knowledge for the MCAT exam. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:03) Overview of Biomolecule Structure and Importance (02:37) Steroid Structure and Function (06:36) Nucleotide Structure and Function (12:02) DNA Structure and Bonding (16:30) Carbohydrate Structure (19:53) Disaccharides and Polysaccharides (24:47) Fatty Acids and Phospholipids (28:57) Cholesterol and Its Role in Membrane Fluidity (31:27) Sphingolipids and Their Functions (33:02) Eicosanoids: Signaling Molecules (38:12) Heme Groups and Their Functions (41:12) Molecule Entry into Cells (44:12) MCAT Advice of the Day

In this episode, we're diving deep into the nuanced aspects of metabolism that are essential yet less prominently featured on the MCAT. We'll cover gluconeogenesis, the pentose phosphate pathway, and ketone body generation—topics that, while subtle, play a crucial role in your comprehensive understanding of biochemistry.  We'll explore how your body manages glucose levels, the functions of NADPH, how glycogen is synthesized and broken down, and the metabolic adaptations during periods of low glucose.  Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:54) Pentose phosphate pathway overview (02:42) Functions of NADPH in the body (03:35) Difference between NADPH and NADH (04:34) Key points to know about the pentose phosphate pathway (07:01) Insulin and glucagon: hormonal regulation of blood glucose (09:00) Effects of insulin & glucagon on the body (10:48) Glycogen synthesis & breakdown (15:51) Glycogen debranching enzyme and breakdown of branched chains (18:49) Bypassing irreversible steps in glycolysis during gluconeogenesis (21:19) Regulation of gluconeogenesis (22:25) Ketogenic amino acids and their role in ketone body formation (24:04) MCAT advice of the day: reading journal articles

In this episode, Sam Smith covers the intricacies of metabolism, focusing on glycolysis, the Krebs cycle, and the electron transport chain.  First, the podcast explores the process of glycolysis, breaking down the key enzymes, intermediates, and regulation points. Next is the citric acid cycle, examining its regulation, energy production, and the roles of specific enzymes and intermediates. Lastly, we look at the electron transport chain and discuss how electrons are transferred through the five complexes, creating a proton gradient that drives ATP synthase to produce ATP.  Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (03:15) Ten steps of glycolysis: Intermediate names and enzymes (08:01) Simplified glycolysis process: Breaking down key steps (12:30) Glycolysis regulation: Allosteric regulation of enzymes (21:13) Mnemonics for Krebs cycle intermediates (25:52) Regulation of the Krebs cycle: ATP, calcium, and more (30:26) Electron transport chain: Overview and key steps (34:35) ATP synthase (33:00) Reduction potentials in the electron transport chain (37:31) Synopsis of metabolism (40:34) MCAT Advice of the Day  

Acids and bases are foundational topics in chemistry, crucial for understanding various biological and chemical systems you'll encounter in the MCAT. In this episode, host Sam Smith discusses the selection and use of indicators in titrations to the pH at the equivalence point and the importance of buffers in maintaining physiological pH levels. You'll learn about the Henderson-Hasselbalch equation, the blood buffer system, and how to tackle common problems involving acids and bases. Plus, we'll break down strong and weak acids and the significance of their dissociation constants. This episode also shares tips on calculating pH, using ICE tables for weak acid problems, and converting between pH, pOH, and ion concentrations. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (02:16) Basic definitions of acids and bases (11:33) Calculating pH (24:55) Titrations (35:26) Buffers (41:16) Blood buffer system (45:25) MCAT advice of the day

A foundational topic for the MCAT is the nervous system, appearing in several exam sections and impacting everything from neurotransmission to brain structure. In this episode, Sam Smith walks us through the nervous system, covering its major components and functions. From the organization of the central and peripheral nervous systems to neurotransmitters and brain structures, Sam provides clear explanations to help you understand key topics like the autonomic nervous system's fight-or-flight response, brain imaging techniques, and more.  Visit medschoolcoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:03) How the central and peripheral nervous systems are organized (02:33) Autonomic and somatic systems (03:22) Sympathetic and parasympathetic branches (04:12) How the brain is structured: forebrain, midbrain, and hindbrain (11:44) How brain imaging techniques (CT, MRI, EEG, fMRI, PET) are used (14:06) How neurons are structured and how they transmit signals (16:00) How action potentials work and how ion channels play a role (20:30) How myelin sheaths speed up signals (25:00) How language processing happens in Broca's and Wernicke's areas (28:00) Neurological disorders (43:45) The structures of the limbic system (47:25) The structures of the brain related to addiction    

Amino acids are the building blocks of life and an essential topic for the MCAT. In this episode, host Sam Smith takes us through the key concepts of amino acids, including their structures, naming conventions, and roles in protein formation. We’ll cover the differences between hydrophobic and hydrophilic amino acids, how to memorize single-letter abbreviations, and the importance of charged amino acids in physiological conditions. Additionally, Sam touches on mutations and how they can affect protein folding and enzyme function. Visit medschoolcoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:47) Amino acids naming conventions and abbreviations (04:49) Hydrophobic vs. hydrophilic amino acids (05:39) Charged and uncharged amino acids (10:14) Explanation of mutation notation (11:53) Mutations affecting the substrate pocket of enzymes (13:15) Mutations impacting enzyme functionality (15:58) Role of amino acids in protein tertiary structure (17:15) Salt bridges and protein stability (20:47) Quiz

One of the body's key survival mechanisms is gluconeogenesis, a vital metabolic process, and the body's clever way of making glucose when supplies are low. On this episode of the MCAT Basics podcast, guest host Alex Starks walks through the process of gluconeogenesis. He explains how the body generates glucose when levels drop. Highlighting the liver's role, Alex explains how amino acids, lactate, and glycerol are converted into glucose. The episode also touches on the energy demands of the process and why muscle cells aren't involved in gluconeogenesis.  Visit medschoolcoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (02:15) Overview of glucose metabolism and glycogen storage (03:37) The liver’s role in maintaining blood glucose levels (05:11) Glucogenic amino acids and their role in glucose production (06:06) Conversion of alanine and glutamine to pyruvate (06:53) Lactate and the Cori cycle (07:34) Glycerol from triglycerides entering gluconeogenesis (08:27) The first bypass reaction: Pyruvate to oxaloacetate (09:55) The role of mitochondria and the malate-aspartate shuttle (11:00) Phosphoenolpyruvate formation and energy requirements (12:16) Steps of gluconeogenesis and ATP consumption (13:38) The second bypass reaction: Fructose 1,6-bisphosphate to fructose 6-phosphate (14:16) The third bypass reaction: Glucose 6-phosphate to glucose (15:31) Gluconeogenesis regulation and the role of glucagon (17:10) Quiz  

The electron transport chain is a fundamental pathway in biochemistry, critical for understanding the energy production that powers cellular function. In this episode, guest host Alex Starks breaks down the intricate process of the electron transport chain (ETC). Building on previous discussions of glucose metabolism, Alex walks through the components that play key roles in the movement of electrons through complexes within the inner mitochondrial membrane. We also cover the functions of coenzyme Q and cytochrome c, as well as oxygen’s critical role in completing the process.  Visit medschoolcoach.com for more help with the MCAT.   Jump into the conversation: (00:00) Intro (02:11) Recap of glycolysis, pyruvate, and the Krebs cycle (03:02) Location of the TCA cycle and ETC in the mitochondria (04:22) Overview of NADH and FADH2 production (05:38) Complex I: NADH dehydrogenase and coenzyme Q (08:00) Complex II: Succinate dehydrogenase and FADH2 (11:15) Complex III: Cytochrome c reductase and the role of proton pumping (14:32) Complex IV: Cytochrome c oxidase and oxygen (18:14) The role of ATP synthase (21:47) Total ATP yield from aerobic respiration (26:00) How the electron chain is disrupted (30:20) Uncouplers and their metabolic effects (35:16) Quiz  

One of the most fundamental biochemical processes is the Krebs cycle. This metabolic pathway plays a critical role in both the Chem Phys and Bio/Biochem sections of the MCAT, so understanding it is key. In this episode, our guest host, Alex Starks, walks us through the transformation of pyruvate into acetyl CoA via the Pyruvate Dehydrogenase Complex (PDC). We’ll explore how thioester bonds help transfer energy within the cycle, how acetyl CoA combines with oxaloacetate to form citrate, the difference between enzymes like synthetases and synthases, and how GTP is produced. We’ll also make connections to the electron transport chain and discuss how the TCA cycle influences blood pH through CO2 production. Visit medschoolcoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:05) Recap of glycolysis and pyruvate (02:45) Pyruvate dehydrogenase complex (PDC) (03:40) Role of acetyl CoA in the Krebs cycle (05:37) How citrate is formed  (07:17) How isocitrate is formed (10:00) How alpha-ketoglutarate is formed (13:42) How  succinate and GTP are formed (16:28) How succinate, fumarate and oxaloacetate are formed (18:23) Fumarate converted to malate (21:53) Recap of the Krebs cycle and ATP yield (25:00) Regulation of the Krebs cycle (26:16) Quiz  

In this episode, guest host Alex Starks introduces the Metabolism series by examining glycolysis, a fundamental biochemical pathway for energy production. The discussion covers glucose digestion, the role of insulin and glucose transporters, and the step-by-step breakdown of glucose within cells. Alex also offers a detailed explanation of how glucose is processed to generate energy and outlines the key reactions involved. This episode provides a thorough overview of glycolysis offers valuable study strategies for mastering this topic on the MCAT. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:08) Overview of metabolism and starting the series (02:41) Digestion and absorption of glucose into the bloodstream (04:10) The liver’s role in glucose transport and GLUT2 (05:05) The role of insulin in glucose uptake by muscles and fat cells (07:48) Trapping glucose in the cell with glucose phosphorylation (09:32) Glycolysis Step-by-step breakdown of glycolysis (17:41) NADH and ATP production during glycolysis (22:30) Pyruvate and NADH fates in anaerobic and aerobic respiration (25:12) Quiz: Metabolism quiz and study tips for the MCAT

In this episode, we focus on biosignaling and cover how cells communicate through systems like voltage-gated and ligand-gated ion channels, using real-world examples such as neuronal signaling and muscle contraction. We also break down the role of enzyme-linked receptors, specifically receptor tyrosine kinases (RTKs), and explore how these pathways are involved in cell growth and cancer. Additionally, we take a detailed look at G-protein coupled receptors (GPCRs) and their role in activating secondary messenger systems like cyclic AMP (cAMP). Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (00:32) Overview of Biosignaling (01:05) Introduction to Biosignaling and its Importance (01:49) Stimulus-Response Concept: Fight or flight, glucose homeostasis, transcription regulation (02:34) Voltage-Gated Ion Channels: Activated by changes in membrane potential (03:29) Action Potential: Sodium channels and signal propagation (05:01) Ligand-Gated Ion Channels: Role in neuron-to-neuron signaling (06:01) Muscle Contraction: Acetylcholine's role in skeletal muscle contraction (07:29) Misconception on Calcium: Sodium initiates muscle cell depolarization, not calcium (08:33) Enzyme-Linked Receptors: Focus on receptor tyrosine kinases (RTKs) (09:39) RTKs and Cancer: How RTK signaling pathways are linked to cancer (12:00) G-Protein Coupled Receptors (GPCR): Structure and function of GPCRs (14:43) Adenylate Cyclase and cAMP: Role of GTP in activating adenylate cyclase and producing cAMP (18:10) Quiz Question 1: Ion specificity in potassium channels (22:54) Quiz Question 2: Hypertension treatment and G-protein pathways (25:00) Biosignaling as the foundation for cellular responses  

In this episode, guest host Alex Starks dives into Gas-Phase Concepts for the MCAT. He breaks down the physical properties of gases, explores the ideal gas law, and unpacks the ABCD laws of gases. Alex also covers key conditions that influence molecular collisions in gases and highlights the most important takeaways to help you excel in this section of the exam. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro: Med School Coach promotion and podcast introduction (02:01) Physical properties of gases (06:03) The ideal gas laws (09:40) Conditions that promote molecular collisions in gases (10:34) The ABCD gas law (13:02) The Van der Waals equation (14:33) Gas laws quiz (16:29) Key takeaways  

In this episode, we focus on the lymphatic system, a crucial topic for the Bio/Biochem section of the MCAT. We'll cover the structure of the lymphatic system, including lymphatic vessels, lymph nodes, and major organs such as the bone marrow and thymus. You'll also learn about the system’s primary functions: returning fluid to the blood, supporting the immune system, and absorbing fats and fat-soluble nutrients. Hosts Sam Smith and Alex Starks break down how the lymphatic system plays a vital role in immunity, nutrient absorption, and fluid balance. By the end of this episode, you'll gain a deeper understanding of the lymphatic system's anatomy and physiology, helping you prepare for MCAT-related questions. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro: Med School Coach MCAT Tutoring Promotion (01:01) Episode Introduction: Lymphatic System Overview (01:07) Co-Host Introduction: Sam Smith and Alex Starks (01:19) Episode Outline: Structure and Functions of the Lymphatic System (02:39) Structure of the Lymphatic System: Vessels, Nodes, and Organs (04:06) Lymph: Composition and Role in the Body (04:44) Lymphatic Vessels and Their Role in Transport (06:50) Primary and Secondary Lymphoid Organs: Bone Marrow, Thymus, and Lymph Nodes (09:10) Bone Marrow and B-Cell Maturation (09:45) Thymus and T-Cell Maturation

In this episode, we dive into psychological disorders, a crucial topic for the Psych/Soc section of the MCAT. We’ll start by defining what a psychological disorder is, highlighting key concepts like significant stress and deviant behavior, and discussing how they’re classified using the DSM-5. You'll learn about various categories of disorders, including anxiety disorders, obsessive-compulsive disorders, trauma and stressor-related disorders, and more. We’ll explore the biopsychosocial and biomedical approaches to understanding these conditions, providing insight into the biological, psychological, and social factors that contribute to mental health issues. By the end of this episode, you'll have a comprehensive understanding of the different types of psychological disorders and how they are categorized and treated, helping you tackle related questions on the MCAT. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro: Med School Coach promotion and podcast introduction (01:03) Overview of Psychological Disorders: Episode topics and structure (02:13) Defining Psychological Disorders: Significant stress and deviant behavior (05:29) Biopsychosocial vs. Biomedical Approaches: Holistic vs. traditional perspectives (09:18) DSM-5 Classification of Psychological Disorders: Overview of main categories (10:37) Anxiety Disorders: Fear and anxiety beyond normal levels (16:43) Obsessive-Compulsive Disorder: Obsessions and compulsions explained (18:20) Trauma and Stressor-Related Disorders: PTSD and related disorders (19:19) Somatic Symptom Disorders: Physical symptoms causing mental distress (22:01) Bipolar and Related Disorders: Mood swings and differentiating Bipolar I and II

In this episode, we cover the respiratory system, an important topic for the MCAT Bio/Biochem section. We'll go over the anatomy of the respiratory system, highlighting key structures such as the lungs, bronchi, bronchioles, and alveoli, and explain how they contribute to respiratory functions. You'll also learn about the main roles of the respiratory system, including gas exchange, thermoregulation, particle filtration, and maintaining blood pH. We’ll break down the mechanics of breathing, including the role of the diaphragm and intercostal muscles, and how pressure changes drive air into and out of the lungs. We also cover the importance of pulmonary surfactant in preventing alveolar collapse and how partial pressures influence gas movement. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:02) Overview: Functions of the respiratory system (01:28) Main Functions: Gas exchange, thermal regulation, particle filtration, pH control (02:20) Upper Respiratory Tract: Nose, nasal cavity, sinuses, larynx, trachea (05:00) Lower Respiratory Tract: Lungs, bronchi, bronchioles, and alveoli (09:28) Airflow Pathway: How air travels through the respiratory system (10:23) Gas Exchange: Oxygenation and CO2 removal (11:27) Breathing Mechanics: Diaphragm and intercostal muscles (13:04) Pressure Differentials: How pressure changes drive airflow (15:01) Surface Tension in Alveoli: Importance of pulmonary surfactant (18:17) Lung Compliance and Elasticity: How lung tissue stretches and returns to shape (21:48) Gas Exchange Process: Partial pressures of oxygen and carbon dioxide (24:59) Partial Pressure Explained: Role in moving gases during respiration (30:31) Thermoregulation: Maintaining body temperature through respiration (35:59) Particle Filtration: Nasal hairs and mucous cilia system (39:44) pH Regulation: How breathing controls blood pH (41:18) Respiratory Control: Involuntary and voluntary mechanisms, brainstem functions

In this episode, we focus on DNA mutations and repair, a key topic for the Bio/Biochem section of the MCAT. We'll cover the different types of mutations, including point mutations, insertions, and deletions, and explain how they occur due to replication errors or environmental factors like UV radiation. You'll also learn about the repair mechanisms that fix these genetic changes, such as direct reversal, mismatch repair, and base excision repair. We’ll also discuss how double-strand breaks are addressed through homologous recombination and non-homologous end joining. By the end of this episode, you'll gain a thorough understanding of how mutations happen and the processes the body uses to repair them, helping you prepare for related MCAT questions. Visit MedSchoolCoach.com for more help with the MCAT. Jump into the conversation: (00:00) Intro (01:07) Overview of DNA Mutations and Repair (01:45) What is a Mutation? (02:30) Mutations During DNA Replication (03:29) DNA Polymerase Slippage: Causes duplication of repeated sequences in DNA (06:15) Mutations Before or After Replication: Caused by mutagens like radiation or chemicals (07:19) Mutagens vs. Carcinogens: Differences between agents that cause mutations and those that cause cancer (09:56) Types of Mutations: Overview of point mutations, insertions, and deletions (12:00) Frameshift Mutations: How insertions or deletions shift the reading frame (29:50) Chromosomal Mutations: Inversions and translocations (35:35) DNA Repair Mechanisms: Introduction to replication repair, mutation repair, and break repair (36:51) Proofreading by DNA Polymerase: Repairing replication errors (39:20) Direct Reversal DNA Repair: Enzymes directly fix damaged DNA (40:41) Mismatch Repair: Fixing base mismatches and insertion-deletion loops (43:25) Base Excision Repair: Correcting single-base mutations (46:03) Nucleotide Excision Repair: Fixing bulky DNA damage like pyrimidine dimers (47:56) Interstrand Cross-Link Repair: Repairing DNA strands covalently cross-linked together (50:27) Single-Strand Break Repair: Ligating broken DNA strands back together (51:16) Double-Strand Break Repair: Homologous recombination and non-homologous end joining (54:13) Summary of DNA repair mechanisms