RESPIRATION -MWANAMISI.POWER POINT PRESENTATION

RESPIRATION

1. RESPIRATION OVERVIEW The respiratory system is a vital biological system responsible for exchanging gases (oxygen and carbon dioxide) between the body and the environment. It includes the lungs and airways (trachea, bronchi, bronchioles), as well as structures like the diaphragm and chest wall. The primary function of the respiratory system is to deliver oxygen to the blood, which then distributes it throughout the body, while also removing carbon dioxide, a waste product of cellular respiration

2. RESPIRATORY ORGANS The primary respiratory organs are the lungs, but the entire respiratory system includes the nose, mouth, pharynx (throat), larynx (voice box), trachea (windpipe), and bronchi, all working together to facilitate gas exchange and respiration

3. RESPIRATORY ORGANS Nose and Mouth: These are the entry points for air, with the nose also playing a role in warming, moistening, and filtering the air. Pharynx (Throat): This common pathway for both air and food helps move air down towards the lungs. Larynx (Voice Box): Contains vocal cords, and helps regulate airflow and produce sound. Trachea (Windpipe): A tube that carries air from the larynx to the bronchi. Bronchi: These tubes branch into smaller airways (bronchioles) that lead to the lungs. Lungs: The main organs of the respiratory system, where gas exchange (oxygen in, carbon dioxide out) occurs between the air and blood. Diaphragm: A muscle that helps with breathing by expanding and contracting the chest cavity

4. RESPIRATORY ORGANS

5. MECHANISM OF BREATHING Breathing, or respiration, is a two-step process: inspiration (inhaling) and expiration (exhaling). Inspiration involves the diaphragm and external intercostal muscles contracting, expanding the chest cavity and drawing air into the lungs. Expiration is typically passive, involving the relaxation of these muscles, which reduces the chest cavity volume and forces air out

6. MECHANISM OF BREATHING Inspiration (Inhalation): Diaphragm Contraction: The diaphragm, a sheet-like muscle beneath the lungs, contracts and moves downward, increasing the space in the chest cavity. Intercostal Muscle Contraction: The external intercostal muscles between the ribs contract, pulling the rib cage upwards and outwards, further expanding the chest cavity. Pressure Change: The expansion of the chest cavity lowers the pressure inside, creating a pressure gradient that draws air into the lungs from the outside. Airflow: Air flows from the nose or mouth down the trachea (windpipe), through the bronchial tubes, and into the alveoli (tiny air sacs) in the lungs.

7. MECHANISM OF BREATHING Expiration (Exhalation): Diaphragm Relaxation: The diaphragm relaxes, returning to its dome shape and reducing the space in the chest cavity. Intercostal Muscle Relaxation: The intercostal muscles relax, causing the rib cage to return to its resting position. Pressure Change: The reduced chest cavity volume increases the pressure inside, pushing air out of the lungs. Airflow: Air flows out of the lungs through the bronchial tubes, trachea, and out of the nose or mouth

8. CONTROL OF EXTERNAL RESPIRATION External respiration, the exchange of gases between the lungs and the bloodstream, is primarily controlled by neural and chemical signals originating from the brainstem and other areas. The respiratory center , located in the medulla oblongata and pons, integrates inputs from various sources to regulate breathing rate and depth

9. CONTROL OF EXTERNAL RESPIRATION Neural Control: Respiratory Center : The respiratory center , composed of several neuronal groups in the medulla and pons, receives signals from chemoreceptors and higher brain centers . Medulla: The medulla contains the dorsal respiratory group (DRG) and ventral respiratory group (VRG). The DRG primarily controls inspiration, while the VRG stimulates expiration and controls the rate and depth of breathing. Pons: The pontine respiratory group (PRG) helps regulate the transition between inspiration and expiration. Higher Brain Centers : Higher brain centers , such as the cerebral cortex, allow for voluntary control of breathing

10. CONTROL OF EXTERNAL RESPIRATION Chemical Control: Chemoreceptors: Chemoreceptors monitor blood levels of oxygen, carbon dioxide, and pH. Peripheral Chemoreceptors: Located in the carotid and aortic bodies, these receptors detect changes in oxygen and carbon dioxide levels in arterial blood. Central Chemoreceptors: Located in the medulla, these receptors respond to changes in carbon dioxide levels in the cerebrospinal fluid. CO2 and Oxygen Levels: Increased CO2 ( hypercapnia ) or decreased oxygen (hypoxia) stimulates the respiratory center to increase ventilation. pH: Changes in blood pH, often caused by alterations in CO2 levels, can also affect respiratory rate and depth

11. CONTROL OF EXTERNAL RESPIRATION Additional Factors: Upper Airway Receptors: Stimulation of receptors in the upper airways can trigger reflexes that affect breathing. Motor Neurons: The respiratory center sends signals through motor neurons to the respiratory muscles, such as the diaphragm and intercostal muscles, to control breathing. Autonomic Nervous System: The autonomic nervous system, particularly the sympathetic and parasympathetic branches, can influence breathing rate and depth

12. GAS EXCHANGE Gas exchange is the process where oxygen enters the blood and carbon dioxide exits, driven by diffusion across a surface, like the lungs. This exchange occurs in the lungs between the alveoli and capillaries, with oxygen moving from the alveoli to the blood and carbon dioxide moving from the blood to the alveoli.

13. GAS EXCHANGE Key aspects of gas exchange: Diffusion: Gases move from areas of higher concentration to areas of lower concentration. Surface Area: Large surface areas, like those in the lungs, facilitate efficient gas exchange. Thin Walls: Thin walls, like those of the alveoli, allow for easy diffusion of gases. Ventilation and Perfusion: In the lungs, ventilation (air movement) and perfusion (blood flow) are crucial for gas exchange. Partial Pressure Gradients: Differences in partial pressure between the alveoli and blood drive the diffusion of gases

14. GAS EXCHANGE Tissues: Gas exchange also occurs in the tissues, where oxygen is released from red blood cells and carbon dioxide is taken up by the blood. External vs. Internal Respiration: External respiration (gas exchange in the lungs) is distinct from internal respiration (gas exchange in the tissues).

15. GAS EXCHANGE

16. GAS TRANSPORT In the respiratory system, gas transport involves the movement of gases like oxygen and carbon dioxide between the lungs, blood, and tissues.

17. GAS TRANSPORT 1. Respiratory Gas Transport: Ventilation: Involves the movement of air into and out of the lungs. Gas Exchange: Oxygen moves from the lungs to the bloodstream, while carbon dioxide moves from the blood to the lungs. Convection and Diffusion: Gas transport in the lungs utilizes convection (bulk flow) and diffusion (movement of molecules). Circulatory System: The circulatory system (heart and blood vessels) supports gas transport by delivering oxygen to tissues and removing carbon dioxide.

18. MEASURING FUNCTION Measuring respiratory function involves assessing how well the lungs and airways work, including their ability to exchange gases and move air efficiently. Common methods include spirometry , lung volume tests, gas diffusion studies, and exercise stress tests. Spirometry is a basic test that measures the amount of air you can breathe in and out, as well as how fast you can exhale

19. MEASURING FUNCTION 1. Spirometry : This test measures how much air you can breathe in and out of your lungs, as well as how quickly you can exhale. A spirometer is a device that measures the flow of air through the lungs. It helps identify and monitor conditions like asthma, COPD, and other lung diseases. Common measurements include forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and the ratio of FEV1/FVC.

20. MEASURING FUNCTION 2. Lung Volume Tests ( Plethysmography ): These tests measure the total amount of air your lungs can hold and the amount of air left after you exhale as completely as possible. Body plethysmography , a type of lung volume test, is often considered the most accurate way to measure lung volumes. 3. Gas Diffusion Tests: These tests measure the efficiency of gas exchange between the lungs and the bloodstream, specifically the transfer of oxygen and carbon dioxide. One example is measuring the diffusing capacity of the respiratory membrane (DLCO), which assesses the transfer of carbon monoxide from the lungs to the blood

21. MEASURING FUNCTION 4. Exercise Stress Tests : These tests evaluate how exercise affects lung function by measuring how the heart and lungs respond to physical activity. A cardiopulmonary exercise test (CPET) measures various parameters during exercise, such as oxygen consumption, carbon dioxide production, and heart rate. 5. Other Tests: Pulse oximetry : Measures oxygen saturation in the blood, providing a quick assessment of oxygen levels. Arterial blood gas: Measures the levels of oxygen, carbon dioxide, and pH in the blood, offering a more in-depth view of respiratory function. Exhaled nitric oxide: Measures the amount of nitric oxide in your breath, which can indicate airway inflammation, especially in asthma. Flow-volume loops: These are graphs that visualize airflow during forced breathing maneuvers , helping to diagnose and monitor lung diseases.

22. URINARY SYSTEM The urinary system, also known as the renal system, is responsible for filtering waste and excess fluid from the blood, producing urine, and eliminating it from the body. It consists of the kidneys, ureters, bladder, and urethra.

23. URINARY SYSTEM Key Components: Kidneys: The main organs of the urinary system, responsible for filtering blood and producing urine. Ureters: Tubes that carry urine from the kidneys to the bladder. Bladder: A temporary reservoir for urine, collecting it until it's time to urinate. Urethra: The tube that carries urine from the bladder to the outside of the body

24. URINARY SYSTEM Functions: Filtration: The kidneys filter blood, removing waste products and excess fluid. Urine Production: The filtered waste and fluid become urine. Transport: The ureters transport the urine to the bladder. Storage: The bladder stores the urine temporarily. Elimination: The urethra carries urine out of the body

25. URINARY SYSTEM

26. ORGANS Key organs and their functions: Kidneys: These bean-shaped organs are located on either side of the spine, below the rib cage. They filter blood, removing waste and excess fluid to produce urine. Ureters: These thin tubes carry urine from the kidneys to the bladder. Bladder: This hollow, expandable organ stores urine until it's time to urinate. Urethra: This tube carries urine from the bladder out of the body

27. URINE FORMATION Urine formation is a three-step process: filtration, reabsorption, and secretion, all occurring within the kidneys. The kidneys filter blood, remove waste products like urea, and then reabsorb necessary substances back into the bloodstream

28. URINE FORMATION 1. Filtration: Blood enters the kidneys and flows through the glomerulus, where a filtration membrane separates water and small solutes from the blood. This filtered fluid, called filtrate, then moves into the renal tubules. 2. Reabsorption: As the filtrate travels through the renal tubules, essential substances like water, glucose, amino acids, and electrolytes are reabsorbed back into the bloodstream, leaving the unwanted substances behind.

29. URINE FORMATION 3. Secretion: The renal tubules also selectively remove excess ions, toxins, and other wastes from the blood and secrete them into the filtrate. 4. Concentration: The remaining filtrate, now urine, is then further concentrated as it moves through the collecting ducts, where the concentration of urine can be adjusted based on the body's hydration status.

30. KIDNEY FUNCTION CONTROL Kidney function is controlled through a combination of neural and hormonal mechanisms, alongside factors like blood flow and filtration rates. The kidneys filter the blood, remove waste, and regulate blood pressure, electrolyte balance, and red blood cell production.

31. KIDNEY FUNCTION CONTROL 1. Neural Control: Renal Sensory Nerves: These nerves, located in the renal pelvic wall, play a role in regulating renal blood flow and sodium excretion. Sympathetic Nervous System: Increased sympathetic activity reduces renal blood flow and sodium excretion, and increases renin secretion.

32. KIDNEY FUNCTION CONTROL 2. Hormonal Control: Renin-Angiotensin System (RAS): Renin, produced by the kidneys, activates the RAS, leading to vasoconstriction, increased blood pressure, and sodium reabsorption. Antidiuretic Hormone (ADH): Released by the hypothalamus, ADH increases water reabsorption in the kidneys, helping to regulate blood volume and pressure. Erythropoietin (EPO): EPO, produced by the kidneys, stimulates red blood cell production in the bone marrow, helping to maintain oxygen levels.

33. KIDNEY FUNCTION CONTROL 3. Blood Flow and Filtration: Renal Blood Flow: The kidneys receive a large amount of blood, and a decrease in blood flow can negatively impact kidney function. Glomerular Filtration Rate (GFR): GFR is the rate at which fluid is filtered through the glomeruli, the tiny filters in the kidneys. A healthy GFR indicates proper kidney function.

34. KIDNEY FUNCTION CONTROL 4. Other Factors: Diet: A healthy diet, low in sodium and processed foods, can help support kidney health. Hydration: Staying hydrated is crucial for kidney function, as it helps flush out waste and maintain proper fluid balance.

35. KIDNEY FUNCTION CONTROL Exercise: Regular exercise can help improve cardiovascular health and support overall kidney function. Medications: Certain medications, like NSAIDs, can negatively impact kidney function, and should be used with caution or under the guidance of a medical professional. Chronic Conditions: Conditions like diabetes and high blood pressure can lead to kidney damage.

36. BODY FLUIDS REGULATION Body fluid regulation involves mechanisms to maintain a stable internal environment, including water balance and electrolyte levels. The kidneys, nervous system, and hormones play crucial roles in regulating fluid volume, osmolality, and electrolyte concentration.

37. BODY FLUIDS REGULATION 1. Key Players in Regulation: Kidneys: Primarily responsible for regulating fluid volume, osmolality, and electrolyte concentrations through glomerular filtration, tubular reabsorption, and tubular secretion. Nervous System: The hypothalamus, particularly the osmoreceptors , senses changes in plasma osmolality and triggers the release of antidiuretic hormone (ADH). Hormones: ADH (also known as vasopressin) increases water reabsorption in the kidneys, while aldosterone regulates sodium and potassium balance.

38. BODY FLUIDS REGULATION 2. Mechanisms of Regulation: Thirst: As fluid is lost and sodium levels increase in the bloodstream, thirst is triggered to promote fluid intake. ADH: When plasma osmolality increases, ADH is released, causing the kidneys to retain water, increasing blood volume and lowering osmolality. Renin-Angiotensin-Aldosterone System (RAAS): This system is activated when blood pressure drops or sodium levels decrease, leading to increased sodium and water retention. Natriuretic Peptides: These hormones, released from the heart, promote sodium and water excretion, opposing the effects of RAAS.

39. BODY FLUIDS REGULATION 3. Fluid Compartments: Intracellular Fluid (ICF): Fluid within cells, making up a larger portion of the body's water. Extracellular Fluid (ECF): Fluid outside of cells, further divided into plasma (fluid in blood) and interstitial fluid (fluid between cells). Transcellular Fluid: Specialized fluids like cerebrospinal fluid, synovial fluid, and fluid in the GI tract. 4. Importance of Regulation: Maintaining Plasma Volume: Essential for adequate tissue perfusion and blood pressure. Regulating Plasma Osmolality: Critical for maintaining cell volume and function, as changes in osmolality can cause cell shrinkage or swelling, potentially leading to neurological damage or death. Electrolyte Balance: Maintaining proper electrolyte concentrations is vital for nerve and muscle function, as well as other physiological processes

40. BODY FLUIDS REGULATION 5. Clinical Considerations: Dehydration: Excessive fluid loss can lead to low blood volume, reduced blood pressure, and impaired kidney function. Fluid Overload: Excessive fluid intake or retention can cause edema (swelling), high blood pressure, and potential cardiac complications. Electrolyte Imbalances: Can result from various conditions, such as kidney disease, medications, or gastrointestinal issues, and can lead to serious health problems

41. URINE ELIMINATION WATER AND ELECTROLYTES BODY FLUID DISTRIBUTION Body fluids are distributed in two main compartments: intracellular fluid (ICF) within cells and extracellular fluid (ECF) outside cells. ICF makes up about two-thirds of total body water, while ECF makes up about one-third

42. BODY FLUID DISTRIBUTION Intracellular Fluid (ICF): The fluid within the cells, encompassing the cytoplasm. Makes up approximately two-thirds of total body water (about 28 liters in a 70 kg adult male). Contains a high concentration of potassium, phosphate, and magnesium, and a low concentration of sodium and chloride

43. BODY FLUID DISTRIBUTION Extracellular Fluid (ECF): The fluid outside the cells, including interstitial fluid, plasma, and transcellular fluid. Makes up about one-third of total body water (about 14 liters in a 70 kg adult male). ECF is further divided into: Interstitial fluid: Fluid in the spaces between cells. Plasma: The fluid portion of blood. Transcellular fluid: Specialized fluids like cerebrospinal fluid, synovial fluid, and urine. Contains a high concentration of sodium and chloride, and a low concentration of potassium

44. BODY FLUID DISTRIBUTION Other Key Points: Total Body Water (TBW): The sum of ICF and ECF, typically around 60% of total body weight in adults, with slight variations based on factors like age, gender, and body fat. Fluid Movement: Water moves between compartments by osmosis, moving from areas of higher water concentration to areas of lower water concentration. Fluid Balance: The body tightly regulates fluid balance to maintain osmotic equilibrium and overall health. Electrolytes: Electrolytes like sodium, potassium, and chloride play a crucial role in fluid balance and are distributed differently between ICF and ECF

45. FLUID AND ELECTROLYTES BALANCE ACID BASE BALANCE