Human Anatomy & Physiology Introduction PDF

0. Introduction Course Human Anatomy & Physiology Status Complete Materials 0. Introduction to Physiology - Slides Textbook Chapter 1 Date...

0. Introduction Course Human Anatomy & Physiology Status Complete Materials 0. Introduction to Physiology - Slides Textbook Chapter 1 Date @August 27, 2024 Important Themes in A&P Biological Hierarchy Hierarch Organization Levels of the Body Homeostasis The Regulatory Mechanism Negative Feedback Mechanism Components Thermoregulation/Temperature Homeostasis Glucose Homeostasis High blood glucose Low blood glucose Response of Effecters to Chemical Signals Type I Diabetes 0. Introduction 1  Type II Diabetes Examples of Negative Feedback Mechanisms Positive Feedback Mechanisms Anatomy is the study of structure Physiology is the study of function ana / TOM / y : process of physi / o / LOG / y : study of cutting up nature ana: up, toward, apart ic, ical, y: pertaining to TOM: cut Physi : nature y: action, process, or LOG: study condition Important Themes in A&P Complementarity of structure and function or form reflects function. Order: living things have a precise, recognizable structure Energy: life requires energy Hierarchal organization: Living things form a hierarch. Homeostasis: the existence of a constant stable internal environment distinct from the changing external environment Biological Hierarchy The study of life extends from the microscopic scale of molecules and cells to the global scale of an entire living planet and beyond. 0. Introduction 2  Hierarch Organization Hierarch: is a structure built of many levels, a sequence from simple to complex Each level: depends on the level below it is formed from building blocks from the level below exhibits an emergent property or new property not seen or predicted in level below great diversity within but only few become building blocks for the next level Building block: is a component used in a variety of, but precise ways to form a more complex structures Emergent property: is a new property that appears at a level. Examples: life is emergent property of cells. Thinking is emergent property of the brain. Levels of the Body The levels from smallest to largest are: 0. Introduction 3  Chemical: includes atoms, molecules, macromolecules, organelles. Atoms: smallest units of matter that combine to form more complex molecules Cell: is the structural and functional unit of life or is the smallest living unit. Function: depends on Organism: the total of all levels that specialization or stucture of work together to promote life and cell (organelles and proteins) involves the coordination of organ Tissue: a group of similar cells that systems perform the same function Organs: discrete structures composed of 2 or more tissues that perform a specific function Systems: different organs that work together to accomplish a common purpose Homeostasis Homeostasis: the existence of a constant stable internal environment distinct from the changing external environment Property of cells and organisms exhibited by living things Loss of or imbalance results in disease Is achieved by negative feedback mechanisms (regulatory mechanism) The Regulatory Mechanism 0. Introduction 4  Regulatory Mechanism: is a response to a stimulus Stimulus: is a detected change in a variable Response: is the activity that occurs as a result of a stimulus Two types: Negative feedback: the response corrects the stimulus is how homeostasis is achieved Positive feedback: amplifies the stimulus Negative Feedback Mechanism Components Receptor (sensor): detects a change in the environment Afferent Path: carries info (sensory) to control center Control center: receives info, decides based on a set point range and sends a command (motor info) Efferent path: carries command to effector Effector: performs the response and is a muscle or gland Thermoregulation/Temperature Homeostasis 0. Introduction 5  Stimulus: rise in temperature Stimulus: fall in temperature Receptor: in skin Receptor: in skin Afferent path: nerve fibers Afferent path: nerve fibers Control center: brain Control center: brain Efferent path: nerve fibers Efferent path: nerve fibers Effector: sweat glands & blood Effector: muscle contraction & vessels dilation to skin blood vessel constriction to skin Response: decrease in body temperature Response: increase in body temperature Glucose Homeostasis Glucose levels in blood fluctuated throughout the day increasing after a meal decreasing between meals Set point is 90 mg /100 ml Antagonistic actions of insulin and glucagon maintain homeostasis 0. Introduction 6  High blood glucose Stimulus: High blood glucose Receptor & Control Center: Glucose transporter in cell membrane of beta cells of pancreas detect & trigger secretion of insulin (chemical signal) Afferent Path: None Efferent Path: Insulin (chemical Low blood glucose signal) picked up by blood and Stimulus: Low blood glucose travels to target cells Receptor & Control Center: Alpha Effectors: Mainly in liver, muscle cells of the pancreas act as and adipose tissue (contain receptor and control center receptor for chemical signal) secreting glucagon (chemical Response: Glucose levels fall signal) because cells take up glucose and Afferent Path: None stores it or burns it to form energy Efferent Path: Glucagon is picked to make other cell products up by blood and travels to target cells 0. Introduction 7  glucose transporter is Effectors: Mainly in liver (contain activated receptor for chemical signal) i.e. transporter stored in Response: liver cells release vesicles fuses with cell glucose increasing blood glucose membrane resulting in cells levels taking in more glucose liver converts glycogen into increase cell respiration results glucose (glycogenolysis) in more energy for anabolic If no glycogen: glucose is reactions formed from protein (using i.e. fat storage, protein skeletal muscle) synthesis i.e. gluconeogenesis liver converts glucose into glycogen (glycogenesis) i.e. storage form of glucose Response of Effecters to Chemical Signals Insulin: Removal of glucose from Glucagon: Release of glucose into blood or increase uptake of blood from cells glucose via glucose transporter Cells produce glucose: Increase use of glucose by 1. break down of glycogen into cells: glucose 1. ATP formation (cellular 2. Formation of glucose from respiration) proteins (gluconeogenesis) 2. anabolic reactions: fat and protein synthesis that use up ATP 3. store glucose (glycogen synthesis) Type I Diabetes Type II Diabetes 0. Introduction 8  Due to loss of beta cells, no insulin Due to weight gain and insulin is produced and requires resistance replacement Symptoms: Symptoms: Constant high blood glucose Polyphagia (hunger) and levels stress cells weight loss (cells are starving have enough energy (i.e. so use up all reserves). Cells glucose/ATP) cannot use glucose so instead use proteins (muscle wasting) cannot use more so down and fat regulate or remove glucose transporters High blood glucose levels and Polyglycourea: high blood do not respond to insulin glucose levels are toxic so (insulin resistance) glucose is dumped into urine Pancreas responds by Polydipsia: thirsty because secreting more insulin because glucose is an osmoticum blood glucose levels remain pulling water out of blood into high urine With time pancreas wears out Polyurea: frequent urination producing insulin sporadically or not at all Ketourea: Ketones appear in urine (byproduct of a Lifestyle disease metabolism dominated by fat) Examples of Negative Feedback Mechanisms Stimulus Glucose Pain Temp Receptor Pancreas Pain Receptors Temp Receptors A. Path N/A Nerve Fiber Nerve Fiber Control Center Pancreas Spinal Cord Hypothalamus E. Path Bloodstream Nerve Fiber Nerve Fiber, Hormone Effector Muscles, Liver Muscles Muscles, Gland 0. Introduction 9  Heat Loss or Glucose Uptake or Response Withdrawl Production Release (shivering/sweating) Positive Feedback Mechanisms Positive Feedback Mechanism: Rare mechanisms that amplify a response Once started must go to completion Examples: blood clotting, labour 0. Introduction 10