Test #2 Flashcards
Def: Cardiac Output
The amount of blood pumped by heart per minute
Def: Stroke Volume
Blood pumped during each heartbeat (ml/beat)
Def: Cardiac Reserve
Difference between cardiac output at rest and maximum cardiac output during exercise
Def: Heart Rate
Number of times heart meats per minute (beats/min)
What is the equation for calculating cardiac output
CO=HRxSV
Def: Intrinsic Regulation
Results from normal functional characteristics, not on neural or hormonal regulation
Def: Extrinsic Regulation
Involves neural and hormonal control
What 3 factors regulate stroke volume
preload, afterload, contractility
Def: Preload
The amount of stretch of the ventricular walls before contraction
Frank-starling law of the heart
The greater the preload, the greater the force of contraction because stretching of the sarcomeres optimizes the overlap into a range for the highest pumping. Increased EDV= increased stretch on the walls=optimized overlap of actin and myosin = increased force of contraction = increased stroke volume
Def: Venous Return
Amount of blood returning to the heart from systemic circulation, which determines EDV. Can be affected by skeletal muscle contractions known as muscle pump
How does muscle pumping work
Skeletal muscles squeeze area of the veins to actively pump the blood toward the heart
Def: Afterload
The pressure the contracting ventricles must produce to overcome the pressure in the aorta and move blood into the aorta
Def: Contractility
The forcefulness of contraction of the ventricle muscle fibers, which is controlled by inotropic agents
Def: Inotropic Agents
Substances which increase or decrease contractility of the ventricle muscle fibers
Def: Positive Inotropic Agents
open Ca2+ channels of the cardiac accelerator nerves which release the neurotransmitter norepinephrine and the hormone epinephrine from the adrenal medulla
Def: Negative Inotropic Agents
Drugs such as calcium channel blockers and beta blockers (decrease oxygen demand)
Factors which regulate HR (7)
Autonomic nervous system, hormones, ions, age (increases but max decreases), gender (females higher at rest), physical fitness (decreased at rest), temperature (increase in temp increases HR)
Parasympathetic Nerve Stimulation Control of Heart Rate
Vagus nerve decreases heart rate. Neurotransmitter acetylcholine hyperpolarizes the heart causeing more K+ channels to open
Sympathetic Nerve Stimulation Control of Heart Rate
Cardiac accelerator nerves increase heart rate. NE released at the SA/Av nodes opens more Ca2+ channels
Hormonal Control of Hearth Rate
Epinephrin and NE are release from the adrenal medulla. Acts slower but last longer. Acts as a backup system
Effects of blood pressure
Baroreceptors monitor blood pressure in the internal carotid arteries and aorta, sensory information goes to centers in the medulla oblongata
Effects of pH, Carbon dioxide and oxygen
Chemoreceptors detect pH and CO2 changes in the medulla oblongata through the CSF, and chemoreceptors monitor O2 in the carotid and aortic bodies
Effects of extracellular ion concentration
excess or reduced extracellular K+ decreases heart rate
Effect of body temperature
Heart Rate increases when temperature increases, HR decreases when body temperature decrease
Baroreceptor and Chemoreceptor reflex
- sensory neurons: Baroreceptors and chemoreceptors, 2. parasympathetic nervous system: Vagus nerve which innervates SA Node and dreceases HR 3. Sympathetic Nervous System: cardiac nerves which increase HR and myocardium contractility 4. SNS acts through the adrenal medulla to release epinephrine and NE
Functions of Blood
Transportation of gases, nutrients and waste products, transportation of processed molecules, transportation of regulatory molecules, regulation of pH and osmosis, maintenance of body temperature, protection against foreign substances and clot formation
Composition of Blood
55% plasma, 45% formed elements
Def: Plasma
The liquid portion of the blood which contains 91% water, 7% proteins and 2% other solutes
Proteins in Plasma
Albumins 58%, Globulins 38% and Fibrinogen 4%
Albumins
Most abundant protien in blood plasma, maintains osmotic pressure and transports fatty acids, bilirubin and thyroid hormones
Globulins
Antibodies and transportation of lipids, iron and hormones (mainly sex hormones)
Fibrinogen
Responsible for blood clotting
Formed elements
Comprised of 95% red blood cells (erythrocytes), 5% white blood cells (leukocytes) and platelets
Red Blood Cells (Erythrocytes
Biconcave discs with no nucleaus or mitochondria. Contain hemoglobin to transport oxygen and carbon dioxide. converts CO2 and H2O to carbonic acid for bicarbonate buffer
White Blood cells (Leukocytes)
Protect body against microorganisms and remove dead cells and debris. Comprised of Granulocytes which are large granules that have multi-lobed nuclei and Agranulocytes which are small granules and have non-lobed nuclei
Platelets
Cell fragments that form platelet plugs and release chemicals for blood clotting, have surface glycoproteins which allow for adhesion to other molecules
Precursor Cell to Red Blood Cell
Proerythroblast
Precursor cell to granulocytes
Myeloblast
Precursor cell to lymphocytes
Lymphoblasts
precursor cell to monocytes
monoblasts
precursor cell to platelets
Megakaryoblasts
Components of RBC
1/3 hemoglobin and 2/3 lipids, ATP and carbonic anhydrase
Transport Functions of RBC
Oxygen (98.5% bound to hemoglobin), Carbon Dioxide (23% bound to hemoglobin, 70% bicarbonate) and H+ which is generated from carbonic anhydrase reaction
Hemoglobin
made up of four globin molecules with four heme molecules each with an iron atom
Oxyhemoglobin
Hemoglobin when transporting oxygen
deoxyhemoglobin
Hemoglobin with no oxygen bound
Carbaminohemoglobin
Hemoglobin transporting carbon dioxide
Erythropoiesis
The production of red blood cells, takes about 4 days, RBCs last about 120 days, stimulated by erythropoietin
RBC Recycling
- Natural degeneration of RBC’s 2. separation of components: Globin: recycled into amino acids, Heme: iron removed and recycles and the rest converted into bilirubin
WBC Movements
Ameboid (Arm like movement against walls), Diapedesis (Cells become thin, elongated and move wither between or through endothelial cells of capillaries), Chemotaxis (Attraction to and movement towards foreign materials or damaged cells)
Types of Granulocytes
Neutrophils, eosinophils and basophils
Types of Agranulocytes
lymphocytes and monocytes
Neutrophils
60-70% of WBCs, nuclei have 2-5 lobes, 10-12h circulation or 1-2 d tissues, phagocytize bacteria and foreign matter, secrete lysozyme (an enzyme that metabolizes bacteria)
Eosinophils
2-4% of WBCs, nuclei have 2 lobes, active in allergic reactions, destroy inflammatory chemicals like histamine, release chemicals that help destroy worms
Basophils
0.5-1% of WBCs, inflammation and allergic response of tissues, produces histamine and produces heparin which inhibits blood clotting
Lymphocytes
20-25% of WBCs, smallest, produced in red bone marrow, proliferates in lymphatic tissue, produces antibodies to destroy bacteria containing viruses and tumor cells
Monocytes
3-8% of WBCs, largest, become macrophages after 3 days, phagocytic cells which ingest bacteria, dead cells and cell fragments, increases with chronic infection
Platelet plugs
- platelet adhesion, 2. platelet release reaction, 3. platelet aggregation
Functions of the circulatory system
Carry blood, exchange nutrients, waste products and gases, transport of hormones, components of the immune system, molecules required for coagulation, enzymes, nutrients, gases and waste products, regulate blood pressure, and directs blood flow
Types of blood vessels
Arteries, capillaries and veins
Types of arteries
Elastic (Great vessels leaving heart and direct branches off of them), Muscular ( Thick smooth muscle walls involved in vasoconstriction and vasodilation) and arterioles (smallest levels of arteries and have smooth muscle walls)
Def: Capillaries
Site of exchange with tissues, microscopic vessels that usually connect arterioles and venules, thin walls for exchange
Def: Veins
Thinner walls than arteries, contain less elastic tissue and fewer smooth muscle cells
Types of veins
Venules (smallest and drain from capillaries), small veins and medium and large veins
Layers of the general blood vessel
Tunica intima (tunic interna): innermost layer, adjacent to lumen, Tunica media: middle layer, smooth muslce and elastic fibers, Tunica adventitia (tunica externa): Outermost layer, adjacent to surrounding tissue
Elastic Arteries
Larger diameter, more elastic fibers, less smooth muscles, function as pressure reservoirs, tunica media is the largest, elastic layer merges in intima and media
Muscular Arteries
Medium Diameter, more smooth muscle, fewer elastic fibers, distributes blood to various parts of the body, adventitia is the thickest
Arterioles
Transports blood from small arteries to capillaries, smallest arteries where the three tunics can be differentiated, capable of vasoconstriction and dilation, terminal end called metarteriole
Precapillary Sphincters
Last muscle fibers, blocks blood flow to areas of capillary bed
Thoroughfare Channel
main channel straight through capillary bed
Continuous Capillaries
No gaps between endothelial cells, less permeable to large molecules than other capillary types (eg. muscle or nervous tissue)
Fenestrated Capillaries
Have pores, endothelial cells have numerous fenestrae, which are areas where the cytoplasm is absent and plasma membrane is made of a thin porous diaphragm, highly permeable (eg. intestinal villi, ciliary process of eye, choroid plexus, glomeruli of kidney)
Types of capillaries
Continuous, fenestrated, and sinusoid
Sinusoid Capillaries
Large diameter with large fenestrae, less basement membrance (eg. Endocrine glands, liver, bone marrow)
Venules
Drain capillary network, endothelial cells and basement membrane with a few smooth muscle cells, as diameter of venules increases the amount of smooth muscle increases, postcapillary venules and muscular venules
Veins
Formed form the union of several venules, thinner tunica interna and media than arteries but thicker tunica externa, less elastic and smooth muscle, contain valves
Valves
Found in veins greater than 2mm diameter, folds in intima that overlap, more valves in veins of lower extremities used to prevent backflow
Varicose veins
Dysfunctional valves, mostly in the lower limbs, causes blood pools in veins resulting in swelling, pain and ulcers. Causes include pregnancy and defective valves
Vasa Vasorum
Blood vessels that supply the walls of the arteries and veins penetrate vessel walls form the exterior
Portal Veins
2 in-series capillary network. Examples: Hepatic portal veins (GI to spleen to Liver) and Hypophyseal portal vein (hypothalamus to anterior pituitary gland)
Pulmonary Circulation
From right ventricle into pulmonary trunk, pulmonary trunk divides into left and right pulmonary arteries, two pulmonary veins exit each lung and enter left atrium
Systemic Circulation through the arteries
Aorta (exits left ventricle and is divided into 3 parts), 1. Ascending aorta: Right and Left coronary arteries branch from here 2. Aortic arch: extends backwards and branches into brachiocephalic, left common and left subclavian 3. Descending aorta: Thoracic aorta and abdominal aorta
Systemic Circulation through the veins
Major veins: Coronary sinus, superior vena cava, inferior vena cava, can be superficial, deep or sinuses
Def: Blood Flow
Volume of blood that flows through any tissue in any given time period
Def: Pressure
force per unit surface area (blood pushing against blood vessel walls) - mean arterial pressure (driving pressure)
Def: Resistance
Opposing force to the normal blood flow
Relationship between flow, pressure and resistance
flow= change in pressure/ resistance
Calculation for mean arterial pressure
1/3(SBP-DBP) +DBP
Where does the greatest drop in blood pressure occur
In the arterioles, no large fluctuations in capillaries and veins
Laminar flow
Can’t flow, streamlined, outermost layer moves slowest due to friction and center moves fastest
Turbulent Flow
Non-laminar flow, fluid passes a constricted, sharp turn or rough surface, partially responsible for heart sounds
What is a Korotkoff sound
The sounds that occur when measuring blood pressure as the blood begins to move back through the arteries
Calculation of resistance
resistance= (viscosity or blood x length of tube) / diameter of the vessel^4
Velocity of blood flow
Blood flow is inversely related to cross-sectional area of blood vessels, as well as being affected by pressure
Process required for respiration
Ventilation (movement of air into and out of the lungs), External respiration ( gas exchange between air in lungs and blood) and internal respiration (gas exchange between the blood and tissues)
Respiratory system function
regulation of blood pH (Through bicarbonate system), production of chemical mediators (Angiotensin converting enzyme), voice production, olfaction, protection)
Upper Respiratory tract
External nose, nasal cavity, pharynx and larynx
Lower Respiratory tract
bronchi and lungs
Naris
External opening to nasal cavity where air enters
Hard plate
seperates oral and nasal cavities
Vestibule
made of stratified squamous, with hairs that are used to trap particles
Concha
A superior, middle, and inferior version, ridges in the walls that help create turbulence and increase surface area for mucus membranes
Paranasal Sinuses
Frontal sinus and sphenoidal sinus, make skull lighter, lined with mucus membrane, secrete into nasal cavity, also help with speech production
Meatuses
Superior, middle and inferior versions, passage ways for air to move through located between concha
Choana
internal naris
Cells of nasal cavity
pseudostratified ciliated columnar with goblet cells, warms air due to vascularity, moistens air and traps dust, cilia move mucus toward pharynx
Functions of the Pharynx
Passageway for food and air, resonating chamber for speech production, immunological functions
Location of the pharynx
Extends form choanae to esophagus, 13cm muscular tube
Tonsils
3 tonsils: pharyngeal, palatine and lingual
Regions of the Pharynx
Nasopharynx, oropharynx, laryngopharynx
Soft Palate
Made of muscle and mucus membrane that closes nasal cavity when swallowing
Uvula
Extends off of soft plate and aids in closure of nasal cavity when swallowing
Fauces
Opening between the oral cavity and the pharynx
Nasopharynx
Posterior to choanae/ superior to soft plate, passage of air only
Oropharynx
soft palate to epiglottis, Common passageway for air and food
Laryngopharynx
epiglottis to esophagus, common passageway for air and food
Structure of the Larynx
3 unpaired pieces of cartilage, 6 in pairs
Unpair cartilage of the larynx
Epiglottis, thyroid cartilage and cricoid cartilage
Epiglottis
leaf shaped flap of elastic cartilage that covers the larynx will swallowing
Thyroid Cartilage
AKA adams apple, maintain opening
Cricoid Cartilage
right of cartilage, maintains opening
Paired cartilage of the larynx
Arytenoid, corniculate and cuneiform
Arytenoid Catilage
articulates with the cricoid cartilage and attaches to the vocal folds
Corniculate Cartilage
Articulates with the arytenoid cartilage
Cuneiform Cartilage
imbedded in ligaments and soft tissue, supports lateral structure of vocal cords
Vestibular Folds
False vocal cords located adjacent to vocal folds
Glottis
Vocal opening, includes the opening and vocal folds
Trachea Structure
12 cm, extends from larynx to T5, 16 - 20 C-shaped rings of hyaline cartilage to support dense regular CT and smooth muscle ( opened at back to accommodate esophagus), lined with pseudostratified ciliated columnar which propels matter toward pharynx
