Anatomy and Physiology: Eyes and Vision PDF

# ANATOMY AND PHYSIOLOGY ## TOPIC: EYES AND VISION ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## EYES AND VISION - Retina = receptive layer of the eye that converts light energy to neural impulses. - Optic nerve - Brain - Occipital lobe: interpreted as sight - Pupil = A...

# ANATOMY AND PHYSIOLOGY ## TOPIC: EYES AND VISION ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## EYES AND VISION - Retina = receptive layer of the eye that converts light energy to neural impulses. - Optic nerve - Brain - Occipital lobe: interpreted as sight - Pupil = A black-looking aperture, that allows light to enter the eye - dark due to the absorbing pigments in the retina). - Iris = A colored circular muscle that gives the eye color. This circular muscle controls the size of the pupil - Cornea = A transparent external surface, This is the first and most powerful lens of the optical system of the eye and allows, together with the crystalline lens, the production of a sharp image at the retinal photoreceptor level. - Sclera = The "white of the eye", = forms part of the supporting wall of the eyeball, continuous with the cornea. ### Three layers: - **The external layer** 1. sclera 2. cornea. - **The intermediate layer** 1. iris 2. ciliary body 3. choroid). - **The internal layer/sensory part** 1. retina. ### Three chambers of fluid: - **A. anterior chamber** (between cornea and iris), aqueous humor - **G. posterior chamber** (between iris, zonule fibers and lens) aqueous humor - **C. vitreous chamber** (between the lens and the retina). vitreous humor. (more viscous) **Accommodation** = changes the shape of the lens that allows the formation of sharp image on the retina. - **fovea centralis:** Finest detail. Point of Keenest vision **Aqueous humor:** fluid in the front and rear chambers of the eye. It is a clear, watery fluid that flows between and nourishes the lens and the cornea; it is secreted by the ciliary processes. **Central vision:** fine, sharp, straight-ahead vision **Choroid:** a thin vascular layer between the sclera and the retina. - **supplies blood to the retina and conducts arteries and nerves to other structures in the eye.** **Ciliary body:** a thin vascular (blood vessel-filled) middle layer of the eye. **Conjunctiva:** A thin, clear, moist membrane that coats a. palpebral area; the inner surfaces of skin b. bulbar area; outer surface and muscle that can be closed over the eyeball or opened at will. **Lacrimal gland:** A small almond-shaped structure that produces tears and is located just above the upper, outer corner of the eye. **Lens:** The transparent structure inside the eye that focuses light rays onto the retina. **Macula:** a small spot where vision is keenest in the retina. **Lacrimal gland:** A small almond-shaped structure that produces tears and is located just above the upper, outer corner of the eye. **Optic nerve:** connects the eye to the brain. - **The optic nerve carries the impulses formed by the retina and dispatches the image to the brain for interpretation.** **Orbital area:** pertaining to the orbit, the bony cavity that contains the eyeball. - Suspensory Ligaments - RODS - CONES - Macula - Fovea centralis **Near Vision or Near Point**= the minimum distance an object can be seen at focus. **CONVERGENCE:** the ability of the eye to focus brought about by the elasticity of the lens. **BINOCULAR OR STEREOSCOPIC VISION**= perception of depth **Visual Acuity**= the smallest print at which a client could read the lines without errors. **ASTIGMATISM**= the cornea or lens are not perfectly smooth. - **Ophthalmoscopy:** - + diopter = Hyperopia = far sightedness - diopter = myopia = near sightedness - **o Normal Emmetropia** - **CONSENSUAL LIGHT REFLEX** - **COLOR BLINDNESS** - **ISHIHARA TEST PLATES** - **RHODOPSIN:** = Photosensitive pigments of the eye. - **Positive After image**= seeing a colored image against a dark background - **Negative after Image**= seeing a dark image against a colored background # ANATOMY AND PHYSIOLOGY ## EARS AND HEARING ## EARS, HEARING AND BALANCE ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## Outer ear 1. **pinna** - also known as the auricle -external ear part - made up of cartilage and soft tissue. - helps in maintaining a particular ear shape - remains pliable. - like a funnel that collects the sound vibration 2. **external auditory meatus.** ### External auditory meatus - is also called the ear canal. - extends from the pinna to the tympanic membrane. - Skin and hair cover the outer ear canal. - (+) cerumen gland or the wax gland is present in this area. ### Eardrum - is a very sensitive organ. - Transferred to the inner ear for further - vibrates according to the frequency and the amplitude of sounds that strike it. ### Middle ear - begins at the end of the tympanic membrane. - (+) three tiny bones (ossicles) - Ossicles connect the eardrum to the inner ear. - Sound waves >>> pinna >>> eardrum >>> ossicles move >>> convertion into mechanical vibration. - Middle ear is present in the mastoid section of the temporal bone ### Eustachian tube - runs from the middle ear front wall to the back of the nose and nasopharynx - provide ventilation and access to the external air and balance the air pressure on the both sides of the eardrum. ## Inner ear - (+) sensory organs that help in hearing and maintaining balance. ### Cochlea = involved in the function of hearing - snail-like bony structure filled with endolymph and perilymph - inside is the Organ of Corti - It has hair cells and nerve receptors, required for hearing. - the actual organ that helps sin hearing functions as a sound wave interpreter and converter. ### Ears maintain balance of the body. - Semicircular help in balancing 1. utricle 2. saccule ### The three tiny bones forming the ossicles 1. malleus also known as the hammer is connected to the eardrum on one side or the anvil on the other side, 3. stapes. = stirrup connected to the stapes - The sound waves converted into mechanical energy are transferred through this ossicular chain. There is an in and out movement at the stirrup base known as the stapes footplate, that matches the incoming sound waves. The beginning of the inner ear is marked by the oval window that fits in the stapes footplate. >> The sound waves converted into mechanical energy are transferred through this ossicular chain. ### Inner ear is marked by the oval window that fits in the stapes footplate. ### Vestibular system - sense of equilibrium - vestibular. present in the inner ear. - fluids present in the cochlea are present in the vestibular. **Note :**Many other systems like vision, muscle response, help the vestibular system in performing its balancing function - semicircular canals 1. utricle 2. saccule - angle to each other. - These planes each have a specific function that deals with movement, that is, up and down, side to side and tilting from one side to the other side. - (+) sensory hair cells - activated by the movement of the endolymph fluid. - When the head tilts to one side, the sensory hair cells send a nerve impulse to the brain with the help of acoustic nerve. ## HEARING TESTS - **TICKING STOP WATCH TEST** - **AUDIOMETER** = determines the threshold for hearing for standard frequencies. ### Two Kinds Of Hearing loss 1. **Conduction deafness** = involves the outer or middle ear where mechanical vibrations in the external environment do not reach the cochlea Ex: Blockage, Perforated T.M. 2. **Sensorineural deafness** - Present in Cochlear damage - Vestibulocochlear damage - Problems in the auditory centers of the temporal lobe of the brain ### Tuning Fork Test - **WEBER'S TEST** - **LATERALIZATION OF SOUND** ### Interpretation - Normal no lateralization - **Conductive** = Louder on the defective ear - **sensorineural** = Louder on the ear without hearing loss ### RINNE'S TEST - from mastoid to external ear - (normal) air conduction is GREATER than bone Conduction - Bone conduction is greater than air conduction = Conductive hearing loss ### BARANY's Test - visual response to the changes in dynamic balance - as the head is turned to left or right, the direction of the movement of the eyes are opposite. - **Nystagmus:** twiching of the eyes. ## END OF LECTURE # ANATOMY AND PHYSIOLOGY ## TOPIC: RESPIRATORY SYSTEM ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## RESPIRATORY SYSTEM - **Atmosphere oxygen** - **Lungs** - **circulatory system** - **individual cells of the body** - **carbon dioxide** (metabolic waste product) - released from the intercellular environment - travels via the blood - **Lungs** - exhalation. ### Ventilation - Breathing = "pulmonaryventilation" - Pulmonary means related to the lungs ### Two phases - **Inspiration (inhalation) - air in** - **Expiration (exhalation) - air out** ### Pulmonary ventilation - Air moves in and out of lungs ### External respiration (LUNGS) - **O2 (oxygen) in air diffuses into blood** - **CO2 (carbon dioxide) in blood diffuses into air** ### Internal respiration (TISSUES) - **O2 in blood diffuses into tissues** - **CO2 waste in tissues diffuses into blood** **Note:** - Blood is the transporting fluid ### Purpose of Breathing: 1. Oxygen (O2) is used by the cells 2. Oxygen needed in conversion of glucose to cellular energy (ATP) ### What is the waste product of respiration? Carbon dioxide ### Conducting zone - **Respiratory passages (Tubes) Ex.** - **Bronchus.>** - Filters, humidifies and warms air - **Respiratory Zone** - **of gas exchange (Inside the Lungs)** - **Composed of** - **Respiratory bronchioles, Alveolar ducts, Alveolar sacs** ### End-point of respiratory tree - **Structures that contain air-exchange chambers are called alveoli** - **Respiratory bronchioles lead into alveolar ducts: walls consist of alveoli** - **Ducts lead into terminal clusters called alveolar sacs** ### Nasus or nose - **nasal cartilages** - **external nares (nostrils)** - **nasal septum.** - **The nasal septum separates the nasal cavities** - **composition:** - **NOSE** - 1. perpendicular plate of the ethmoid bone, - 2. vomer, - 3. septal cartilage. - **Moistens and warms air** - **Filters air** - **Resonating chamber for speech** - **Olfactory receptors** ### Nasal cavity - **NARES** - **Nasal septum divides nasal cavity in midline** - **Nose is connected to the pharynx through a nasal aperture known as CHOANAE** - **The floor or base of the nasal cavity is the roof of the mouth called the PALATE:** - **Anterior Palate is hard palate** - **Posterior Palate is soft** ### External nares = (+) guard hairs. - **nasal vestibule** = the region of the nose just posterior to the external nares - **lined with stratified squamous epithelium.** - **nasal cavity = Behind the vestibule** - **= lined with a mucous membrane** ### Function of mucous membrane - moistens air entering the respiratory system - traps dust particles - overlays a superficial venous plexus that warms the air. - **The membrane consists of connective tissue and respiratory epithelium,** ### Respiratory epithelium - **- composed of pseudostratified ciliated columnar epithelium with goblet cells.** - **nasal conchae** - **=three protrusions in the lateral walls of the cavity have that push into the nasal cavity** - **=reclaims moisture as air exits from respiratory system** - **=affects the air swirl into the cavity and come into contact with the mucous membrane** - **Internal nares, or choanae** - **- opening at the back of nasal cavity that leads to pharynx** ## Pharynx - **3 parts: naso-, oro-, and laryngopharynx** - **Oro-nasal cavity** - **Open into nasal cavity** - **Uvula doesn't go into airway** - **Posterior to nasal cavity** - **food passes through for food located airway so food goes to the nose** - **Pharynx is a passageway for food and air** - **Oropharynx and the upper most ** ## Pharynx - **1. Nasopharynx:** the upper nasopharynx is directly posterior to the nasal cavity, and Eustachian tubes. - **2. Orophanyx** - a. auditory, - b. food, and - c. liquid air. - **3. Laryngopharynx:** The most inferior portion of the pharynx which conducts food and air through the larynx. ## Larynx - **"voice box" for sound production** - **continues with trachea (windpipe)** - **consists of nine hyaline cartilages** - **- produces vocalization (speech)** - **1. Vocal Processes of (number) cricoid, inferiorly on each side** - **Switch mechanism to route air and food into proper opening** - **NOTE: During swallowing** - **Open during ** ### Innervation of larynx - **Recurrent laryngeal nerves of Vagus** - **Damage to one: hoarseness** - **Damage to both: can only whisper** - **Three cartilages attach to the posterior end of the vocal folds (true vocal cords)** 1. Thyroid cartilage 2. Cricoid cartilage 3. Arytenoid cartilage - **Corniculate and cuneiform cartilages.** - **Behind thyroid cartilage and above cricoid: 3 pairs of small cartilages** 1. Arytenoid: anchor the vocal cords 2. Corniculate 3. Cuneiform ## Epiglottis - the most superior cartilage in the larynx - cartilage in the larynx - composed of elastic cartilage. - covers the opening of the larynx during swallowing which is known as the glottis. - This cause a reflex called cough reflex - **Epiglottis = During swallowing, larynx is pulled superiorly** - **Epiglottis tips inferiorly to cover and seal laryngeal inlet** - **Keeps food out of lower respiratory tract** - **Glottis is the space between the vocal cords** - **Laryngeal muscles control length and size of opening by moving arytenoid cartilages** - **Sound is produced by the vibration of vocal cords as air is exhaled** ## Trachea and bronchi - **Also known as "windpipe" (straight tube)** ### Tracheal cartilages - **cartilagenous rings that keeps the lumen of the tracheaopen** - **Divides in thorax into two main (primary) bronchi** - **16-20 C-shaped rings of hyaline cartilage** - **Carina the center point at the most inferior portion of the trachea** ### Carina - **= Ridge on internal aspect of last tracheal cartilage** - **Point where trachea branches (when alive and standing (T7)** ### Mucosa highly sensitive to irritants: cough reflex ## Main or primary bronchi - two tubes from the trachea, which enters the lung - Each lung receives air from a primary bronchi - contain hyaline cartilage and are lined with respiratory epithelium. - divide into the lobar or secondary bronchi - segmental or tertiary bronchi. ## Tracheobronchial tree. - structure showing the extensive branching of the bronchi. - Right lung: 3 lobes - Upper lobe, Middle lobe, Lower lobe - Left lung: 2 lobes - Upper lobe, Lower lobe ### Bronchial tree bifurcation - Right main bronchus (more susceptible to aspiration) - Left main bronchus - cardiac notch - an indention occupied by the heart ## Lungs and Pleura - **Location: is located in the pleural cavities on each side of the mediastinum** ### Membranes: 1. parietal pleura = outer membrane on the chest cavity wall 2. visceral pleura = membrane on the surface of the lungs ### Pleural cavity - slit-like potential space filled with pleural fluid - **bronchi** - **bronchioles** - (small respiratory tubules with smooth muscle on their walls). - **respiratory bronchioles** ### Alveoli - **= alveoli - small structures that are attached to the walls of respiratory bronchioles** - **= alveolar ducts - passageways which branches to the alveoli.** - **are air sacs in the lungs that exchange oxygen and carbon dioxide with the blood capillaries of the lungs,** - **alveolar sacs = collective term for Alveoli that are clustered around an alveolar duct.** ### Autonomic stimulation for: Smooth muscle : - **Sympathetic relaxation** - ("bronchodilation") - **Parasympathetic constriction** - ("bronchoconstriction") ### Type I pneumocytes - **make up about 90% of the alveoli** - **composed of simple squamous epithelium like the capillaries that surround the alveoli.** - **note:** The division of the lung into many small sacs tremendously increases the surface area of the lung. - **This increase is vital for the rapid and extensive diffusion of oxygen across the respiratory membranes.** - **Oxygen moves across the respiratory membrane,** ### Components of the respiratory membrane, - **a. alveolus** - **b. capillary epithelium** - **c. basement membrane** ### type II pnuemocytes (septal cells) - **they decrease the surface tension of the lung by secreting surfactant.** - **Emphysema a disease caused by Breakdown of the alveoli.** ### Blood supply - **Lungs get their own blood supply from bronchial arteries and veins** - **>>pulmonary plexus on lung root contains sympathetic, parasympathetic and visceral sensory fibers** ## MUSCLES FOR RESPIRATION ### INSPIRATION - **During inspiration, the dome shaped diaphragm flattens as it contracts** - **This increases the height of the thoracic cavity** - **The external intercostalmuscles contract to raise the ribs** - **This increases the circumference of the thoracic cavity** ### EXPIRATION - **=passive process** - **Inspiratory muscles relax** - **Rib cage drops under force of gravity** - **Relaxing diaphragm moves superiorly (up)** - **Elastic fibers in lung recoil** - **Volumes of thorax and lungs decrease simultaneously, increasing the pressure** - **Air is forced out** ## END OF LECTURE : # ANATOMY AND PHYSIOLOGY ## TOPIC: CARDIOVASCULAR SYSTEM ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## CARDIOVASCULAR SYSTEM: - **The functions of the cardiovascular system are:** 1. to deliver oxygen and nutrients 2. To remove carbon dioxide and other waste products ### Mediastinum - **location of the heart.** - **deep in the thorax between the lungs.** - **contains the heart, the coverings of the heart (pericardia) and other structures** ### Heart is a four-chambered pump with two atria and two ventricles. - **end, = has a pointed end, or apex, and a blunt end, or base.** - **= composed of two large inferior ventricles and two smaller and superior atria.** - **The left ventricle is larger than the right ventricle.** - **atrioventricular sulcus, or groove.= At the junction of the right atrium and the right ventricle.** - **Superior vena cave and inferior vena cava = two vessels that also return blood to the right atrium.** - **Pulmonary veins- carry blood from the lungs to the left atrium.** - **Right ventricle = is much thinner-walled than the left ventricle.** ### PERICARDIUM= Encases the heart & protects it from trauma & infection - Parietal endocardium - Visceral pericardium - Pericardial fluid ## ANATOMY & PHYSIOLOGY ## HEART & LAYERS - **Located at the left side of the mediastinum** - **3 major layers of the heart:** ### Epicardium or serous pericardium - outer most layer - composed of epithelial and connective tissue. ### Myocardium - middle layer/contracting unit - the is the thickest of the three layers. - mostly made of cardiac muscle. ### Endocardium - inner layer of the heart wall. - This is a serous membrane and consists of endothelium (simple squamous epithelium) and connective tissue. ### Fibrous pericardium- tough outer connective tissue sheath encloses the heart. - **Parietal pericardium** - is the inner lining of the fibrous pericardium. - **Serous pericardium** - reduces the friction between outer surface of the heart and the parietal pericardium - **pericardial cavity** = space between serous pericardium (visceral) and parietal pericardium. - **heart-arteries**= layer closest to the heart - **heart-arterioles**= capillaries ### HEART - CHAMBERS - **ventricles** = *capillaries.* - **consists of two upper atria & two lower ventricles** - **consists of two atria** - **chamber of the heart** - **PREVENT BACKFLOW** - **Atrioventricular valve** ### Heart Right - **Right atrium** - de-oxygenated blood from the superior & inferior vena cava then pumps to the pulmonary artery - **Right ventricle ** - receives blood from the right atrium. ### Heart Left - **Left atrium** - receives oxygenated blood from the lungs via the 4 pulmonary venous - **Left ventricle- largest of the chambers, pumps oxygenated blood to the aorta** ### Atrioventricular valve - Closes at the beginning of the ventricular contraction & prevents blood from flowing back into the atria from the ventricles - They open when the ventricle relaxes ### Semilunar valves = prevent the blood from flowing back into the ventricles during relaxation - They open during ventricular contraction & closes when the ventricles relax ### Bicuspid/Mitral valve- - left side - **Tricuspid valve-** - right side ### Pulmonic semilunar valve- right ventricle & pulmonary artery ### Aortic semilunar valve- left ventricle & aorta ### Interventricular septum - **forms a wall between the two ventricular chambers:** - **Right atrium =** the wall ist thin - **sept the interartrial septum the location name of the medial wall.** - **The medial wall of the atrium is known as fossa ovalis = A thin oval depression in the atrial wall.** - **foramen ovale = fossa ovale in fetal hearts** ### Right atrioventricular valve, or tricuspid valve - prevents the return flow of blood from the right ventricle into the right atrium during ventricular contraction. - **chordae tendineae** = thin, tough threadlike / cords that are attached to larger papillary muscles, which are extensions from the wall of the ventricle. - **Trabeculaecarneae** -a small extension of the right ventricle wall. ## REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ### Pulmonary semilunar valve - **appears as three small cusps between the right ventricle and the pulmonary trunk and keeps blood from flowing backwards from the pulmonary trunk into the right ventricle during ventricular relaxation.** ### pulmonary veins - **carry oxygenated blood from the lungs into the left atrium.** ### Bicuspid valve / mitral valve / left atrioventricular valve - **two large cusps between the left atrium and left ventricle** ### Aortic semilunar valves - **prevents the flow of blood from the aorta into the left ventricle.** - **Blood from the left ventricle moves into the aorta and subsequently to the rest of the body.** ## CARDIAC CONDUCTION CYCLE - **Sinoatrial node - also known as pacemaker of the heart, has an intrinsic rate of 60-100 bpm** - **Atrioventricular node - intrinsic rate of 40-60 bpm** ### Conduction system of the heart - Heart contracts as a unit - Atrial and ventricular syncytia help conduct electrical signals through the heart - Sinoatrial (S-A) node is continuous with atrial syncytium - S-A node cells can initiate impulses on their own; activity is rhythmic ### Electrocardiogram (ECG) can trace conduction of electrical signals through the heart ### Regulation of the cardiac cycle - **Parasympathetic:** from medulla oblongata (vagus nerve) - **Nerve branches to S-A and A-V nodes, and secretes acetylcholine (slows rate)** - **Sympathetic nervous system** - **secretes norepinephrine** - **increases force of contractions** ### Medulla oblongata: cardiac control. - maintains balance between the two ### CONDUCTION SYSTEM OF THE HEART - **Sinus Node: Primary Pacemaker of the Heart** - **Bundle of His/ atrioventricular bundle** - specialized muscle fibers in the septum - **Purkinje fibers - where the impulse terminates, resulting to contraction** ### CORONARY BLOOD SUPPLY - **Right and left coronary arteries branch off of aorta** - **Branch into smaller vessels** - **sinus, and back to the right atrium** ### The heart and associated great vessels - **Leaves left ventricle** - **Aorta** ### Pulmonary arteries - **Leave right ventricle** ### Vena cava - **Enters right atrium** - **Pulmonary veins (four)** - **Enter left atrium** ### Blood in the heart chambers does not nourish the myocardium ### The heart has its own nourishing circulatory system - **Coronary arteries** - **Cardiac veins** - **Blood empties into the right atrium via the coronary sinus** ### General circulatory pattern: - **Arteries- vessels that carries blood from the heart** - **Veins- vessels that returns blood to the heart** ### Coronary arteries - **carries blood to from the heart, but they carry the blood to the heart muscle.** - **Cardiac vein- takes the blood from the heart back to the heart for recirculation.** ## CORONARY ARTERIES - **Supplies the capillaries of muscle** - **Right coronary artery:** - Right atrium & ventricle - Posterior septal wall - **Left coronary artery:** - left ventricle posterior - Anterior descending - Left ventricle - Left anterior septum - Apex of the left ventricle - Circumflex artery - Left atrium - Lateral & posterior surfaces of the left ventricle ## DEFINITION OF TERMS: - **Systole** = Contraction of the chambers of the heart. - **Diastole** = Relaxation of the chambers of the heart. - **Baroreceptors** = detect changes in blood pressure - **Rising pressure stretches receptors** - **vagus nerve parasympathetic system** - **Increased temperature >> increases heart rate** - **lons and heart rate:** - **excess potassium decreases it** - **excess calcium increases it** ## REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## Blood pressure - Blood flow is generally equal to cardiac output - Blood flow affected by pressure and resistance - **Blood pressure:** the force that is exerted by blood against blood vessel walls - **Resistance depends on:** - **A. size of blood vessel** - **B. thickness (viscosity) of blood** - **Blood pressure is highest in large arteries** - **will rise and fall as heart pumps** - **highest with ventricular systole** - **lowest with ventricular diastole** - **Pulse pressure is the difference between the two (systolic and diastolic)** - **Resistance is highest in capillaries** ## ILLUSTRATION: - **Control of blood pressure:** - **Regulation of cardiac output** - **contraction strength** - **heart rate** - **venous return** - **ILLUSTRATION:** - **skeletal muscles** - **breathing rate** - **Long term regulation of blood flow (hormones)** - **case: If blood pressure is too low:** - **ADH (antidiuretic hormone) promotes water retention** - **Angiotensin 1 TO 2 by Renin II** - **Stimulation by sympathetic nervous system** ## REVIEWER: - **G.C.E. REBADULLA OD., MD.,RN.,RM** ## DYSRHYTHΜΙΑ ## ELECTRICAL CONDUCTIVITY OF THE HEART - **SYSTOLE: contractions of the heart muscle** - **Atrial systole and ventricular systole** - **DIASTOLE: Relaxation of the heart chambers** - **Atrial and Ventricula diastole** ## ECG: - **Electrical functioning:** - **SA Node or pacemaker** - **AV node** - **Atrioventricular bundle of his** - **Right and left bundle branches** - **PURKINJE FIBERS** - **P WAVE: deflection wave that represent atrial depolarization** - **PQ interval: Time between the beginning of atrial depolarization and the beginning of Ventricular depolarization** - **QRS complex: Represent ventricular depolarization** - **ST Segment. Depolarization.** - **T WAVE: ventricular repolarization** - **Note: Atrial repolarization is masked by a large QRS complex.** ### NORMAL HEART RYTHM - **Cardiovascular System** - **Normal Electrocardiogram** - **Electrical System of the Heart** - **Dysrythmias** - **The AV Node** - **Sinus Node: Primary Pacemaker of the Heart** ## ILLUSTRATION : - **Blood Vessels** ## ILLUSTRATION : -**Arteries and arterioles** -carry blood away from heart - **Capillaries** -site of exchange - return blood to heart - **Venules, veins** - **Endothelium- prevents platelet aggregation** - **secretes substances that control diameter of blood vessel. (INTIMA)** - **Tunica media- smooth muscle and connective tissue. Innervated by sympathetic nerves (vasoconstriction)** - **(Missing in smallest arteries)** - **Tunica externa - connective tissue; is vascularized** ### Three layers (tunics) 1. **Tunic intima** 2. **Tunic media** 3. **Tunic externa** - **Controlled by sympathetic nervous system** - **Mostly fibrous connective tissue** - **Capillary beds consist of two types of vessels** - **Vascular shunt - directly connects an arteriole to a venule** - **True capillaries - exchange vessels** - **Oxygen and nutrients cross to cells** - **Carbon dioxide and metabolic waste products cross into blood** - **Blood is forced through arteries and arterioles** - **vessel walls are too thick for blood components to pass through** - **In capillaries, oxygen and nutrients move out by diffusion; CO2 in (via lipid membrane, channels, etc.)** **NOTES: ** - **Walls of arteries are the thickest** - **Lumens of veins are larger** - **Skeletal muscle "milks" blood in veins toward the heart** - **Walls of capillaries are only one cell layer thick to allow for exchanges between blood and tissue** ### Returning blood to the heart - **Venules are continuous with capillaries; take in some returned fluid (rest is retained by tissues or returned to blood via lymphatic system)** - **Veins have thinner walls; less muscle; but can hold much more blood** - **Many veins in limbs have valves to prevent backflow ** - **(Varicose veins arise when pressure on valves is prolonged)** # ANATOMY AND PHYSIOLOGY ## URINARY SYSTEM ### REVIEWER: G. CLYDE E. REBADULLA. OD.MD.RN.RM.MAP.PGCE ## The Urinary System - **Paired kidneys** - **A ureter for each kidney** - **Urinary bladder** - **Urethra** ### Main Functions of Urinary System - **For Filtration** - **Toxins** - **Metabolic wastes** ### Excretion of nitrogenous wastes from blood - **Urea, Uric acid, Creatinine** - **Regulate the balance of water and electrolytes, and bases** - **BP regulation** - **Production of Erythropoitin** ### LOCATION: retroperitoneal, Superior lumbar of posterior abdominal wall ### SHAPE: - convex: lateral surface - concave: Medial surface - Hilum: Point of entry of blood vessels, ureters and nerves. - **Adrenal glands: Jocated superiorly.** ### Note for: renal pelvis - **Cortex** - **Medulla** - **major and minor calyx** - **Renal pyramid ** ### Two regions - **Cortex: outer** - **Medulla: inner** ### Lobes of the kidney - **Pyramid and cortical tissue surrounding it** - **5-11 per kidney** ### Renal pelvis = Expanded, funnel shaped, - **superior part of ureter** - ***Calyces Collect urine from papilla of Pyramids** - **Minor calyces >>> major calyces >>> pelvis** ### The Arteries - **Aorta** - **Right and left renal arteries** - **Segmental arteries(5)** - **Lobar arteries** - **Interlobar arteries** - **Arcuate arteries (at the junction of medulla and cortex)** - **Cortical arteries** - **Glomerular arterioles** - **Uriniferous tubule is the main structural and functional unit** ### Two major parts 1. **NEPHRON - urine-forming** 2. **A collecting duct which concentrates urine by removing water from it** ### Nephron - **Uriniferous tubule anatomical unit for forming urine.** - **Renal corpuscle (in cortex)** - **Glomerulus (tuft of capillaries)** - **Glomerular (Bowman's) capsule** - **Tubular section (process the filtrate)** - **Proximal convoluted tubule** - **Loop of Henle** - **Distal convoluted tubule** - **Collecting duct** ### 3 main mechanism: - **Filtration** - **a. Fluid is squeezed out of the glomerular capillary bed** - **Resorption** - **b. Most nutrients, water ad essential ions are returned to the blood of the peritubular capillaries** - **Secretion** - **Moves additional undesirable molecules into tubule from blood of peritubular capillaries** ### Nephron - **Renal corpuscle: only in cortex** - **Tuft of capillaries called glomerulus** - **Surrounded by cup-shaped, hollow glomerular (Bowman's) capsule** ### Proximal convoluted tubule - **Confined to renal cortex** - **Resorption of water, ions and solutes** ### Loop of Henle - **Descending limb** - **Thin segment** - **Thick ascending limb** ### Distal convoluted tubule - **Confined to the renal cortex** - **Simple cuboidal epithelium** - **Selective secretion and resorption of ions** ### Collecting Duct - **Each receives urine from several nephrons** - **Run straight through cortex into the deep medulla** - **At papilla