Unit 1 introduction to physiology
Transcript of Unit 1 introduction to physiology
![Page 1: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/1.jpg)
Unit 1: Introduction to Physiology
NRS237 Principles of PhysiologyDr. Moattar Raza Rizvi
![Page 2: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/2.jpg)
• Physiology is the science of studying the functional activities and its mechanisms in biological body.
• For example: why can heart automatically beat?• Physiology derived from two Greek words –
physis = nature; logos = study
What is Physiology?
![Page 3: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/3.jpg)
• Aristotle emphasized the relationship between structure and function
• Galen was the first to perform experiments to understand the function of the body; so known to be father of physiology
• The first “physiologist” of the world, in the modern sense, was William Harvey. In the 17th century William Harvey first describes the circulatory system and its interaction with the body
• Claude Bernard (1813-1878) propounded the concept of milieu interieur or internal environment and established physiology as the scientific basis of medicine.
• THE FATHER OF MODERN PHYSIOLOGY IS THE FRENCH PHYSIOLOGIST CLAUDE BERNARD
The History of Physiology
![Page 4: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/4.jpg)
• Physiology can be divided into viral physiology, bacterial physiology, cellular physiology, plant physiology, human physiology, and many more subdivisions.
• Human physiology is the science of studying the rule of physiological functions in human body.
Field of Physiology
![Page 5: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/5.jpg)
Teleological:•What is purpose or function? •Why does something exist? •Why does it need to be done?
Mechanistic:•What are processes involved?•How does something work?
Function and Process: Teleological vs. Mechanistic Approach to Science
![Page 6: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/6.jpg)
Distinguish between Process & FunctionProcess
• How do we breathe?
• How does blood flow?
• How do RBCs transport O2?
• Why do we breathe?
• Why does blood flow?
• Why do RBC transport O2?
Integrate both for complete picture!
Function
![Page 7: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/7.jpg)
Levels of Structural Organization
![Page 8: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/8.jpg)
Cell Structure and Function
![Page 9: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/9.jpg)
Cell Structure and Function
![Page 10: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/10.jpg)
Cell Structure and Function
Power house of cell
![Page 11: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/11.jpg)
Levels of Structural Organization
![Page 12: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/12.jpg)
Key Themes in Physiology:
1. Homeostasis• Body systems work together (Integration of
function) • Internal vs. external failure of homeostasis
2.Communication and movement across cell membranes • Vital to integration & homeostasis • Cells communicate with other cells, tissues &
organs
![Page 13: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/13.jpg)
Organ System
Integumentary System
DEFINITION The integument (skin) and structures derived from it (hair, nails, and oil sweat glands).
FUNCTIONS Protects the body, regulates body temperature, eliminates wastes, and receives certain stimuli (tactile, temperature, and pain).
![Page 14: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/14.jpg)
Organ SystemDEFINITION Bones, cartilage, and ligaments (which steady the bones at the joints).
FUNCTIONS Provides body support and protection, permits movement and leverage, produces blood cells (hematopoiesis), and stores minerals.
![Page 15: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/15.jpg)
Organ SystemDEFINITION Skeletal muscles of the body and their tendinous attachments.
FUNCTIONS Effects body movements, maintains posture, and produces body heat.
![Page 16: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/16.jpg)
Organ SystemDEFINITION Consists of the lymphatic vessels, lymph nodes, and other lymphatic organs.
FUNCTIONS Removes foreign substances from the blood and lymph, combats disease, maintains tissue fluid balance, and absorbs dietary fats from the digestive tract.
Returns tissue fluids to the heart
![Page 17: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/17.jpg)
Organ System
DEFINITION The body organs concerned with movement of respiratory gases (O2 and CO2) to andfrom the pulmonary blood (the blood within the lungs).
FUNCTIONS Supplies oxygen to the blood and eliminates carbon dioxide; also helps to regulate acid–base balance.
Pharynx is part of digestive and respiratory system
![Page 18: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/18.jpg)
Organ SystemDEFINITION The body organs that render ingested foods absorbable.
FUNCTIONS Mechanically and chemically breaks down foods for cellular use and eliminates undigested wastes.
![Page 19: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/19.jpg)
Organ SystemDEFINITION Brain, spinal cord, nerves, and sensory organs such as the eye and the ear.
FUNCTIONS Detects and responds to changes in internal and external environments, enables reasoning and memory, and regulates body activities.
![Page 20: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/20.jpg)
Organ SystemDEFINITION The hormone-producing glands.•Hypothalamus•Pineal gland•Pituitary gland•Thyroid •Parathyroid •Thymus•Adrenal gland•Pancreas•Ovaries•Testes
FUNCTIONS Controls and integrates body functions via hormones secreted into the bloodstream.
![Page 21: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/21.jpg)
Organ SystemDEFINITION The heart and the vessels that carry blood or blood constituents (lymph) through the body.
FUNCTIONS Transports respiratory gases, nutrients, wastes, and hormones; protects against disease and fluid loss; helps regulate body temperature and acid–base balance.
![Page 22: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/22.jpg)
Organ SystemDEFINITION The organs that operate to remove wastes from the blood and to eliminate urine from the body.
FUNCTIONS Removes various wastes from the blood; regulates the chemical composition, volume, and electrolyte balance of the blood; helps maintain the acid–base balance of the body.
![Page 23: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/23.jpg)
Organ System
DEFINITION The body organs that produce, store, and transport reproductive cells (gametes, or sperm and ova).FUNCTIONS Reproduce the organism, produce sex hormones.
![Page 24: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/24.jpg)
Digestive system Takes in nutrients, breaks them down, and eliminates unabsorbed matter (feces)
Respiratory systemTakes in oxygen and eliminates carbon dioxide
Food O2 CO2
Cardiovascular systemVia the blood, distributes oxygen and nutrients to all body cells and delivers wastes and carbon dioxide to disposal organs
Interstitial fluid
Nutrients
Urinary systemEliminates nitrogenouswastes andexcess ions
Nutrients and wastes pass between blood and cells via the interstitial fluid
Integumentary system Protects the body as a whole from the external environment
Blood
Heart
Feces Urine
CO2
O2
•All cells depend on organ systems to meet their survival needs.
Organ systems work cooperatively to perform necessary life functions
Organ Systems Interrelationships
![Page 25: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/25.jpg)
• In average young adult male:
Body composition
Body composition % of body weight
Protein, & related substances 18%
Fat 15%
Mineral 7%
Water 60%
Body Fluids
![Page 26: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/26.jpg)
• Water content in body is divided into 2 compartments:
1. Extracellular fluid (ECF): (internal environment or the milieu intérieur)
- fluid outside the cells. 1/3 volume of fluids in body ( 33% of total body water). - contains ions & nutrients needed for cellular life.
Extracellular fluid is further divided into A. Interstitial Fluid: Fluid between the cellsB. Plasma: Fluid portion of blood
2. Intracellular fluid (ICF): - fluid inside the cells. 2/3 volume of fluids in body ( 67% of total body water).
Body Fluids
![Page 27: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/27.jpg)
Fluid Compartments 60% of body weight
Extracellular fluid
( 1/3) 33% of TBW
20% of body wt
Intracellular fluid
( 2/3) 67% of TBW
40% of body wt
Interstitial fluid
75% of ECF 15% of body
wt
Plasma 25% of ECF 5% of body
wt
Transcellular fluidCSF
Intraocular
PleuralPeritonea
lPericardia
lSynovialDigestive secretion
s
Fluid Compartments
![Page 28: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/28.jpg)
Body Fluid Compartments
![Page 29: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/29.jpg)
Q. Calculate TBW for a 70 kg man.
TBW = 60% of body weight TBW = 60% X 70 = 42 L of water
• 28 liters intracellular fluid (ICF) – (2/3rd)• 14 liters extracellular fluid (ECF)- (1/3rd)
-3 liters plasma-11 liters interstitial fluid (ISF)
Example: How to calculate total body water (TBW)?
![Page 30: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/30.jpg)
ECFCations:Na+ (142mmol/L)K+ (4.2)Mg2+ (0.8)
Anions:Cl- (108)HCO3
- (24)
Nutrients:
O2, glucose, fatty acids, &
amino acids.
Wastes:
CO2, Urea, uric acid,
excess water, & ions.
ICFCations: Na+ (14)K+ (140)Mg2+ (20)
Anions:Cl- (4)HCO3
- (10)Phosphate ions
Nutrients: High concentrations of proteins.
Differences between ECF & ICF
![Page 31: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/31.jpg)
How Substances Enter and Leave the Cell
![Page 32: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/32.jpg)
How Substances Enter and Leave the Cell
![Page 33: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/33.jpg)
Passive Transport Processes (No cellular energy expended)
Passive transport: Don’t use career protein
![Page 34: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/34.jpg)
Diffusion is movement driven by concentration differences
![Page 35: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/35.jpg)
Diffusion is movement driven by concentration differences
![Page 36: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/36.jpg)
Passive Transport Processes (No cellular energy expended)
Osmosis: Passive transport: Don’t use career protein
![Page 37: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/37.jpg)
Active Transport Processes (Require ATP or other energy sources)
Active transport: Use career protein
Na+ K- pumps 3 Na+ out and 2K+ inside the cell
![Page 38: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/38.jpg)
Active Transport Processes (Require ATP or other energy sources)
![Page 39: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/39.jpg)
Active Transport Processes (Require ATP or other energy sources)
Form vesicle
![Page 40: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/40.jpg)
Homeostasis
Homeostasis homeo-, the same) is the existence and maintenance of a relatively constant environment within the body despite fluctuations in either the external environment or the internal environment.
Walter Cannon coined the term "homeostasis" (1929)
![Page 41: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/41.jpg)
Homeostatic Regulation
This process of adjustment (called homeostatic regulation) involves:1.a receptor (which receives information about a change in the environment),2.a control center (which receives and processes information from the receptor), and3.an effector (which responds to signals from the control center by either opposing or enhancing the stimulus).
1. Receptor2. Afferent Pathway3. Integrating or control center4. Efferent Pathway5. Effector
![Page 42: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/42.jpg)
Feedback
The signal sent by the effector is called feedback; feedback can be either negative or positive.•Negative feedback: when the effector opposes the stimulus (such as a dropping temperature) and reverses the direction of change (causing the temperature to rise). Example: Decrease in Blood Glucose and Blood pressure•Positive feedback: when the effector reinforces the stimulus (such as uterine contractions during childbirth, which trigger the release of the hormone oxytocin) and amplifies the direction of change (causing even greater contractions and further release of oxytocin). Example: Blood clotting, protein digestion, a temperature of 100.2F causes further increase
![Page 43: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/43.jpg)
Negative Feedback Control of Car Speed
![Page 44: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/44.jpg)
Negative Feedback – Temp RegulationResponse to Heat Stress1.Thermoreceptors in skin detect a rise in body temperature2.Nervous system in brain sends message to hypothalamus3.Hypothalamus response:
Sweating: Sweat glands to initiate sweating – evaporation of sweat cools bodyVasodilation: Blood vessels to dilate – more blood glows to skin, which has been cooled by evaporation
![Page 45: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/45.jpg)
Negative Feedback – Temp Regulation
Effector
Effector
Regulator center
![Page 46: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/46.jpg)
Negative Feedback – Temp Regulation1.Thermoreceptors in the skin send a message to
the hypothalamus2.Hypothalamus response:– Vasoconstriction: Constricts smooth muscle of
arterioles – blood flow is limited, heat loss from skin is reduced
– Piloerection: Constricts smooth muscle around hair follicles, causing hair to stand on end – erect hair traps warm air next to skin
– shivering : Skeletal muscles to initiate rhythmic contractions (10 – 20x per minute)
![Page 47: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/47.jpg)
Negative Feedback – Temp Regulation
Regulator center
Effector
Effector
![Page 48: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/48.jpg)
Positive Feedback during childbirth
![Page 49: Unit 1 introduction to physiology](https://reader035.fdocuments.us/reader035/viewer/2022081505/589ad88d1a28abc93a8b699b/html5/thumbnails/49.jpg)
Carry Home Message1.Negative Feedback: Example
1.Decrease in blood glucose2.Decrease in blood pressure
2.Positive Feedback: Example1.Clotting2.Protein digestion3.A temperature of 100.2 0F causes further increase