Anatomy &Physiology I

Transcription

1 Collin College BIOL 2401 Anatomy &Physiology I Why Study Anatomy & Physiology?! You are Entering a medically-related profession.! Planning a career in a biological field.! The course is a requirement for your future career. 1

2 Advantages of this course?! The demand for people educated in Biology and Health Related Aspects is increasing.! Why?! Ageing population with varieties of illnesses! More active population and corresponding injuries! Increased need for skilled personnel capable of handling more complex instrumentation! Ageing nursing population! Today, fully 75% of all hospital vacancies are for nurses.! More than 40% of the current nursing workforce is over 50 years old Advantages of this course? 2

3 Advantages of this course?! Technological advances and Industry look to make health care available to every household.! Home health monitoring is starting to take off = big business Advantages of this course?! This course is a step in preparing people for such future careers such as Nursing, Dental Hygiene, Kinesiotherapy, graduate school,..! The other advantage is.. 3

4 Advantages of this course? YOU OWN A HUMAN BODY! What to Expect for this Course?! This is a 5 weeks course. But it will cover a normal 16 weeks content! You cannot afford to snooze or take a day off.! A science class generally requires 3 hrs study time outside of class for each hour in class.! Example : each day you are in class ~ 5hrs you thus need to study 15 hrs after class. 4

5 How to Study Anatomy & Physiology? That s why you have Fridays off, to catch up with study time! Actively Study each day! (reading is not studying) Create a daily study routine and stick to it. Keep an organized note book, write summaries of what you learned and what you do not understand The best way to memorize it to write and re-write; there is a certain connection between using a pen and your cerebral memory banks Learn the anatomy/physiology terminology now; if a term in unclear, look up its meaning. How to Study Anatomy & Physiology? MINDS ARE LIKE PARACHUTES.. THEY WORK BEST WHEN OPEN! " Don t be afraid to learn and absorb knowledge! " Learning implies studying and correcting your mistakes! " Studying does not mean blindly memorizing it requires memorization, understanding and being able to think outside the box " A negative attitude is lost energy.. 5

6 How to Study Anatomy & Physiology? The workplace requires people who can think, solve problems and remain up to date with new developments! According to a study by Robert Half and CareerBuilder.com, 44 percent of resumes presented to hiring managers are submitted by unqualified applicants. The 2009 EDGE Report also found that 47 percent of hiring managers cited under qualified applicants as their most common hiring challenge. About 61 percent of the hiring managers said they are willing to pay for qualified candidates and would negotiate higher compensation if that meant getting the right person for the job. Collin College Create a daily and weekend study plan and 6

7 Concepts of Anatomy & Physiology Anatomy # The study of structure # Topics include # Gross Anatomy # Microscopic Anatomy/Histology # Developmental Anatomy # Radiographic Anatomy Gross Anatomy 7

8 RadioGraphic Anatomy RadioGraphic Anatomy 8

9 Micro Anatomy Concepts of Anatomy & Physiology Physiology # The study of function. # Physiology strives to understand how the body works and how organs integrate. # Includes molecular and cellular events (cell physiology), organ physiology, patho - physiology The essence of physiology is to reveal the dynamics of organismal life! 9

10 Anatomy Physiology In ALL fields, the study of function is impossible without knowledge of the structure of the parts involved. Function requires knowledge of structure Structure provides clues to function Anatomy Physiology 10

11 Anatomy Physiology Anatomy and Physiology can be studied separately. HOWEVER one can only come to a complete and integral understanding of a biological system by studying both branches together. Function cannot be completely separated from structural aspects nor do structures stand isolated without function. Themes in Physiology # Many phenomena of life can be described in terms of chemical and physical laws # The smallest unit of life is the cell # Certain fundamental features of cell function are shared by virtually all cells # The body s various coordinated functions results from the precise control and integration of specific cellular activities 11

12 Themes in Physiology # Simple examples of applied physical laws Δ Force Δ Voltage Flow = Current = Resistance Resistance Δ = difference in Blood flow = Air flow = Δ Blood Pressure Arterial Resistance Δ Air pressure Bronchiole Resistance Understanding A&P Requires knowledge of Cell biology Includes Cell Chemistry and Metabolism # Atoms, molecules, ions, ph # Carbohydrates, Lipids, Proteins, Nucleic Acids # Enzyme actions, metabolic pathways # Protein Synthesis # Membrane structure and dynamics # Gene Expression and Regulation 12

13 Understanding Patho-Physiology Patho-physiology refers to diseased physiology abnormalities in the physiology. It requires knowledge of normal physiology and additional factors such as nutrition, genetics, immunology,.. Most abnormal events can be traced back to cellular events since the cell is the basic unit of life and the starting point for differentiation in tissues, organs and organ systems There is thus a certain hierarchy and organization in organisms. Hierarchy of the Body Chemical/Molecular Cellular Organism Tissue Organ Organ System 13

14 Levels of Structural Organization 2 Smooth muscle cell Cellular level Cells are made up of molecules. Molecules Atoms 1 Chemical level Atoms combine to form molecules. 3 Tissue level Tissues consist of similar types of cells. 4 Smooth muscle tissue Epithelial tissue Smooth muscle tissue Connective tissue Organ level Organs are made up of different types of tissues. Cardiovascular system Heart Blood vessel (organ) Blood vessels 5 Organ system level Organ systems consist of different organs that work together closely. 6 Organismal level The human organism is made up of many organ systems. Figure 1.1 Organ Systems of the Human Body # The human body can be divided into 11 organ system # These organ system are composed of several kinds of cells, tissues and organs. # Each organ system has its own specialized function. # All organ system work interdependently and are interconnected. # All organ system work interdependently and are interconnected. 14

15 Integumentary System Integumentary Forms the external body covering Organ Systems Composed of the skin, sweat glands, oil glands, hair, and nails Protects deep tissues from injury and synthesizes vitamin D Nervous Composed of the brain, spinal column, and nerves Is the fast-acting control system of the body Responds to stimuli by activating muscles and glands Organ Systems Skeletal Composed of bone, cartilage, and ligaments Protects and supports body organs Provides the framework for muscles Site of blood cell formation Stores minerals Muscular Composed of muscles and tendons Allows manipulation of the environment, locomotion, and facial expression Maintains posture and produces heat 15

16 Endocrine System Composed of all the cells and glands that secrete hormones. Hormones are are transported by the blood and have effects on certain target tissues. They regulate a variety of functions such as growth, metabolism, reproduction, electrolyte balance, CardioVascular System Composed of the heart and blood vessels The heart pumps blood The blood vessels transport blood throughout the body Important for transport of gases, nutrients, waste products, defense mechanisms,. 16

17 Organ Systems Lymphatic/Immune Composed of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels Picks up fluid leaked from blood vessels and returns it to blood Disposes of debris in the lymphatic stream Houses white blood cells involved with immunity Respiratory Composed of the nasal cavity, pharynx, trachea, bronchi, and lungs Keeps blood supplied with oxygen and removes carbon dioxide Digestive Organ Systems Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, and liver Breaks down food into absorbable units that enter the blood Eliminates indigestible foodstuffs as feces Urinary Composed of kidneys, ureters, urinary bladder, and urethra Eliminates nitrogenous wastes from the body Regulates water, electrolyte, and ph balance of the blood 17

18 Reproductive System Male Composed of prostate gland, penis, testes, scrotum, and ductus deferens Main function is the production of offspring Testes produce sperm and male sex hormones Ducts and glands deliver sperm to the female reproductive tract Female Composed of mammary glands, ovaries, uterine tubes, uterus, and vagina Main function is the production of offspring Ovaries produce eggs and female sex hormones Remaining structures serve as sites for fertilization and development of the fetus Mammary glands produce milk to nourish the newborn Maintaining Life The specific organization of the body, depends on specific conditions of several environmental factors such that cells, tissues, organs can work and integrate successfully with each other: Examples include : # Nutrients # Oxygen # Water # Temperature # Atmospheric Pressure And why? 18

19 Homeostasis Because the cells that make up the body require a stable internal environment in order to function properly! # Walter Canon, an American Physiologists, introduced the concept of Homeostasis in # Homeostasis (stability of the internal world) is the overall process in which the body s internal environment remains within certain physiological limits despite drastic outside changes Homeostasis So what is that internal world, environment of the body that needs to be controlled? It is the fluid that surrounds the cells! 19

20 Where are the Body Fluids Located? Total body water in humans ( and most animals ) is located in different compartments. For a 70 kg person, this calculates out to # extra-cellular fluid (ECF) o plasma (fluid in blood vessels): ~ 3 liters o interstitial fluid (in-between the cells) : ~ 11 liters # intra-cellular fluid (ICF) : ~ 28 liters Total water content ~ =42 Liters Distribution of Body Fluids A 70 kg person has thus about 42 kg of water. Or 60 % of body weight is water content. Note : females have more water content than males 11 L 3 L 28 L 20

21 Distribution of Body Fluids Cell membrane Homeostasis and Cell Membranes Barrier between plasma and Interstitial Fluid are the walls of the smallest blood vessels that supply the cells ( the capillaries). These capillaries are very permeable to fluids and smaller molecules but restrict passage of blood cells and proteins. Plasma and Interstitial Fluid thus tend to have similar composition with respect to ions and smaller molecules! 21

22 Homeostasis and Cell Membranes The Cell membrane however provides a selective permeable barrier between Interstitial Fluid and Intra-Cellular Fluid and thus functions as a gate keeper. It determines what goes in and out of the cell. Optimal functioning of a cell depends on optimal conditions of the environment that surrounds the cell, e.g., the ECF The state of the ECF ( e.g. the plasma ) determines the state of the ICF! Electrolyte Distribution is distinct Due to the characteristics of the cell membrane, fluids inside and outside the cell have distinct different chemical composition with respect to cations and anions! What can you tell about the distribution between Sodium and potassium? Between Chloride and proteins? 22

23 Electrolyte Distribution The unequal distribution of the electrolytes between extracellular and intracellular compartments is essential for the function and well being of cell. It should be of no surprise then to learn that the control and maintenance of these unequal distributions is one of the major homeostatic processes constantly at work in order to keep the body in a happy state of being! What organ is of major importance in this control of electrolytes within the extracellular fluid? What is the purpose of doing a blood analysis? Examples of Other Homeostatic values Normal Range Lethal range Potassium mmol/l < 1.0 or > 15 Oxygen mm Hg < 10 CO mm Hg > 80 ph < 6.9 or > 8.0 Body Temp. 37 C > 44 Glucose mg/dl < 20 23

24 Homeostasis What happens if homeostasis is disrupted? # Loss of cellular organization and function # Results in diseased state ( = sickness) If this disruption spirals out of control? # Loss of tissue, organ organization and function # Organ system failure death! Control Mechanisms Disruption of Homeostasis leads to an unstable internal environment and results in disease or even death if not corrected. We are constantly challenged by stress stimuli that create an imbalance in the internal environment. The body has many Control mechanisms and regulatory devices that oppose the forces of stress and bring the internal environment back into balance. Such systems are known as feedback systems. 24

25 Elements of a Feedback system Receptor Afferent pathway Integrating Center Efferent pathway Effector Types of Feedback Systems o Negative Feedback " the response reverses the action of the original stimulus " the variable returns to the ideal, normal value o Positive Feedback " the response causes an increase in the action of the original stimulus " the variable keeps moving away from its previous value 25

26 Negative Feedback System Response Parameter (such as Blood Pressure) Stimulus Stimulus normal range Response Time Negative Feedback System Example : Room Temperature Regulation 26

27 Negative Feedback System Human Example : Body Temperature Regulation Negative Feedback System Example : Blood Glucose Regulation Insulin release Glucagon release 27

28 Positive Feedback System Response Response Response Parameter Stimulus normal range Time In Positive feedback, the system moves away from homeostasis and normal range is lost. However, it speeds up the process. Example : Blood clotting Positive Feedback System 28

29 Activation of Feedback Systems Two major organ systems are constantly at work to monitor deviations from homeostasis and to control the disruptions via feedback systems. Nervous system Acts via neurons Fast acting Short lasting Endocrine System Acts via hormones Slow acting Long lasting However, all body systems come into play when it comes to homeostasis. (why for example would the skeletal system come into play to maintain daily homeostasis?) Activation of Feedback Systems Keep in mind that homeostasis is a state of equilibrium where opposing forces are at work but kept in balance. It is a Dynamic equilibrium the body requires constant and continual adaptation. It is the essence of Physiology : physiological systems work to restore balance and physiology tries to unravel and understand the mechanisms at work. Failure in homeostasis results in disease or death. Failure to understand the mechanisms at work results in bad medicine. 29

30 Bad Medicine: trepenation In ancient times, it was believed that piercing the head would not only cure migraines and epileptic seizures, but could also be used on mentally ill people to allow the bad spirits to escape. Bad Medicine: mercury to the rescue For centuries people believed that Mercury could treat pretty much anything and everything. Mercury is actually extremely toxic and its use most likely helped to accelerate the homeostatic imbalance. In medieval times, it was also used to fight STDs. There was thus a silver lining in its use : the "cure" usually resulted in one less person with syphilis in the world. 30