MCAT Basics (from MedSchoolCoach)

Explore the intricate world of metabolism, focusing on gluconeogenesis and the pentose phosphate pathway. Discover how your body maintains glucose levels through hormonal regulation by insulin and glucagon. Learn about the vital role of NADPH in anabolic reactions and how glycogen is synthesized and broken down. Delve into the formation of ketone bodies from ketogenic amino acids, crucial during fasting. Plus, get essential MCAT study tips to enhance analytical skills and understanding of these biochemical pathways.

Dive into the intricate world of biomolecules, starting with the structural differences between glucose and fructose. Unravel the complexities of glycosidic linkages and learn how fatty acids shape cell membrane architecture. Discover cholesterol's crucial role in membrane stability and the contrasting impacts of LDL and HDL on heart health. Explore the essential functions of steroids and nucleotides, along with the foundational structures of DNA and RNA. Finally, uncover the unique properties of sphingolipids and signaling molecules like eicosanoids.

Dive into the fascinating world of enzymes and their critical role in biological reactions. Explore how enzymes work as catalysts by lowering activation energy and learn about the lock-and-key and induced fit models. Master the Michaelis-Menten equation, which reveals insights on enzyme efficiency and substrate binding. Delve into different types of enzyme inhibition, such as competitive and non-competitive, and understand their effects on activity. Finally, uncover the six major types of enzymes and their biological functions with real-world examples.

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

Dive into the fascinating world of metabolism with a detailed exploration of glycolysis, the Krebs cycle, and the electron transport chain. Unravel the key enzymes and regulation points in glycolysis. Discover how the citric acid cycle drives energy production and the roles of pivotal intermediates. Gain insights into the electron transport chain's function and the creation of ATP through proton gradients. Mnemonics and practical tips for mastering these concepts make it a must-listen for anyone prepping for the MCAT.

Dive into the fascinating world of acids and bases, where foundational chemistry meets biology. Discover the role of indicators in titrations and the critical nature of buffers in keeping our body's pH in check. Learn how to calculate pH, differentiate between strong and weak acids, and utilize ICE tables for problem-solving. The podcast also explores the blood buffer system's function in homeostasis and offers essential strategies for mastering these concepts for the MCAT.

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