Biosignaling

MCAT Basics (from MedSchoolCoach)

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).

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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