Print Human A&P exam 2 flashcards - Easy Notecards

Print Options

← Back to notecard set|Easy Notecards home page

Instructions for Side by Side Printing

Print the notecards
Fold each page in half along the solid vertical line
Cut out the notecards by cutting along each horizontal dotted line
Optional: Glue, tape or staple the ends of each notecard together

To print: Ctrl+PPrint as a list

70 notecards = 18 pages (4 cards per page)

Human A&P exam 2

front 1 Introduction	back 1 The heart – a muscular double pump with two circuits: –Pulmonary circuit— takes blood to and from the lungs –Systemic circuit—vessels transport blood to and from body tissues Atria (‘entranceway’)— receive blood from the pulmonary and systemic circuits ventricles (‘hollow belly’)—the pumping chambers pumps blood around the two circuits
front 2 The Heart...	back 2 Heart pumps blood through 120,000 km (75,000 miles) of blood vessels (BVs) –Beats 100,000 times/day or 35 million times/year –Pumps 5 liters of blood/minute
front 3 Pulmonary and Systemic Circuits	back 3 Pulmonary Circuit: –Right side receives oxygen-poor blood from the body tissues –Pumps this blood to the lungs –Picks up oxygen and dispels CO2 Systemic Circuit: –Left side receives oxygen-rich blood returning from the lungs –Pumps this blood throughout the body –Supplies O2 and nutrients to the body tissues
front 4 Location and Orientation within the Thorax	back 4 Heart: hollow and cone-shaped –About the size of your fist Largest organ of the mediastinum (central compartment of the thoracic cavity) –Located between the lungs –Apex lies to the left of the midline –Base is the broad posterior surface

front 5 Pericardium of the Heart—Coverings	back 5 Pericardium—triple-layered sac that encloses the heart Two primary layers –fibrous pericardium: strong layer of dense connective tissue –Serous pericardium: formed from two layers parietal layer of the serous pericardium Visceral layer of the serous pericardium Pericardial cavity – between the primary layers –Epithelial cells secrete lubricating serous fluid that reduces friction
front 6 Three Layers of the Heart Wall	back 6 *Epicardium* *Myocardium* *endocardium*
front 7 *Epicardium*:	back 7 outer layer of heart wall (and inner visceral layer of serous pericardium) –Thin, transparent layer
front 8 *Myocardium*:	back 8 middle layer of heart wall –Cardiac muscle, responsible for pumping action

front 9 Endocardium:	back 9 innermost, thin layer of heart wall –Simple squamous epithelium –Lines inside of the myocardium –Covers heart valves and tendons attached to the valves –Continuous with the epithelial lining of large blood vessels
front 10 Layers of the Pericardium and of the Heart Wall	back 10
front 11 Arrangements of Cardiac Muscle Bundles	back 11 Myocardium organized in crisscrossing bundles Function to squeeze blood through the heart in the proper directions
front 12 Heart Chambers	back 12 Right and left atria – superior chambers Right and left ventricles – inferior chambers Internal divisions – interventricular and interatrial septa

front 13 External Markings	back 13 –Coronary sulcus forms a crown encircling a boundary between atria and ventricles –Anterior interventricular sulcus
front 14 Right Atrium	back 14 Forms right border of heart: receives oxygen-poor blood returning from systemic circuit via veins –Superior and inferior vena cava and coronary sinus
front 15 Right Ventricle	back 15 Receives blood from right atrium through the tricuspid valve or right atrioventricular (AV) valve Pumps blood into pulmonary circuit via pulmonary trunk
front 16 Internal walls of right ventricle	back 16 –Chordae tendineae: bands attached to cusps of right tricuspid valve –papillary muscles: attached to chordae tendineae

front 17 Pulmonary semilunar valve:	back 17 located at opening of right ventricle and pulmonary trunk
front 18 Left Atrium	back 18 Makes up heart’s posterior surface: receives oxygen-rich blood returning from lungs -Through two right and two left pulmonary veins Opens into the left ventricle through the bicuspid or mitral valve (aka the left atrioventricular valve)
front 19 Left Ventricle	back 19 Forms apex of the heart Internal walls of left ventricle –Chordae tendineae: attached to cusps of left mitral valve –Papillary muscles Superiorly opens into the aorta –Pumps blood through systemic circuit via aortic semilunar valve (aortic valve)
front 20 Heart Valves—Valve Structure	back 20 Paired atrioventricular (AV) and semilunar valves enforce one-way flow of blood through the heart –Designed to prevent back flow in response to pressure changes in the heart chambers Each valve –Two or three cusps

front 21 Heart Valves—Valve Structure	back 21 Atrioventricular (AV) valves lie between atria and ventricles –Right tricuspid valve (3 cusps) –left bicuspid valve (2 cusps) Aortic and pulmonary (semilunar) valves lie at the junction of the ventricles and great arteries –3 cusps
front 22 Heart Valves	back 22
front 23 Function of the Atrioventricular (AV) Valves	back 23 (a) AV valves open; atrial pressure greater than ventricular pressure
front 24 Function of the Atrioventricular (AV) Valves	back 24 (a) AV valves open; atrial pressure greater than ventricular pressure

front 25 Function of the Atrioventricular (AV) Valves	back 25 (a) AV valves open; atrial pressure greater than ventricular pressure Ventricles relaxed --> valves forced open by blood pressure exerted on their atrial side
front 26 Function of the Atrioventricular (AV) Valves	back 26 (b) AV valves closed; atrial pressure less than ventricular pressure
front 27 Function of the Atrioventricular (AV) Valves	back 27 (b) AV valves closed; atrial pressure less than ventricular pressure
front 28 Function of the Atrioventricular (AV) Valves	back 28 (b) AV valves closed; atrial pressure less than ventricular pressure Contraction of ventricles force contained blood superiorly --> valves are pushed shut

front 29 Function of the Semilunar Valves	back 29 Ventricular contraction –Valves pushed open –Cusps flattened against artery walls
front 30 Function of the Semilunar Valves	back 30 Ventricular relaxation –Back flowing blood closes valves
front 31 Pathway of Blood Through the Heart	back 31 Beginning with oxygen-poor blood from the superior and inferior venae cavae (coronary sinus) –Go through pulmonary and systemic circuits –A drop of blood passes through all structures in sequence Atria contract together ventricles contract together
front 32 Blood flow through the heart.	back 32

front 33 Structure of Heart Wall	back 33 Walls differ in thickness –atria—thin walls –Ventricles—thick walls left ventricle generates more force and pumps blood at a higher pressure –Systemic circuit longer than pulmonary circuit –Offers greater resistanceto blood flow
front 34 Structure of Heart Wall	back 34 Left ventricle— three times thicker than right –Exerts more pumping force –Flattens right ventricle into a crescent shape
front 35 Cardiac Muscle Tissue	back 35 Forms a thick layer called myocardium – contains cardiac muscle cells and connective tissue –Cardiac muscle cells Short, branching, 1 or 2 nuclei Cells joined at intercalated discs (complex junctions) Striated like skeletal muscle –Contractions Pump blood through the heart and into blood vessels Sliding filament mechanism
front 36 Cardiac Muscle Tissue	back 36 Intercalated discs – complex junctions between cardiac muscle cells - form cellular networks –Adjacent cells interlock through meshing ‘fingers’ –Fasciae adherens Long junctions bind adjacent cells and transmit contractile force –Gap junctions Allow ions to pass between cells, transmitting contractile signal to adjacent cells

front 37 Blood Supply to the Heart	back 37 Heart walls – too thick to obtain oxygen and nutrients from contained blood—heart needs those substances to beat! Functional blood supply – coronary arteries –Left and right coronary arteries –Arise from the aorta –Located in the coronary sulcus
front 38 Blood Supply to the Heart – Coronary Arteries	back 38
front 39 Blood Supply to the Heart	back 39 Deoxygenated blood from heart wall –Into right atrium –Occupy sulci on the heart surface Coronary sinus – Returns most venous blood from the heart to the right atrium
front 40 Blood Supply to the Heart – Cardiac Veins	back 40

front 41 Blood Vessels	back 41 Delivery system of dynamic structures that begins and ends at heart Arteries Carry blood away from heart Oxygenated except for pulmonary circulation & umbilical vessels of fetus Capillaries Contact tissue cells Directly serve cellular needs Veins Carry blood toward heart Deoxygenated except for pulmonary circulation
front 42 Generalized structure of arteries, veins, and capillaries	back 42
front 43 Structure of Blood Vessels	back 43 Except for the smallest, composed of three layers (tunics) Innermost -> outermost Tunica intima: Endothelium lines lumen of all vessels (simple squamous epithelium) Smooth surface; Continuous with endocardium of heart “Intimate” contact with blood Tunica intima: sheets of smooth muscle & elastic fibers Contraction causes vasocontriction (smaller vessel diameter) Relaxation causes vasodilation (larger vessel diameter) Influence blood flow and blood pressure Tunica externa—composed of connective tissue Contains many collagen and elastic fibers Cells and fibers run longitudinally Vasa vasorum (vessels to the vessels): tiny arteries, capillaries, veins
front 44 Generalized structure of arteries, veins, and capillaries	back 44

front 45 Types of Arteries	back 45 Passage of blood through the arteries: Elastic arteries --> Muscular arteries --> Arterioles
front 46 The relationship of blood vessels to each other and to lymphatic vessels	back 46
front 47 Types of Arteries Elastic Arteries	back 47 elastin in all three tunics Ex. aorta & its major branches Large lumen = low resistance Inactive in vasoconstriction Act as pressure reservoirs—expand and recoil as blood ejected from heart
front 48 Types of Arteries Muscular Arteries	back 48 Distal to elastic arteries Deliver blood to body organs thick tunica media with more smooth muscle Active in vasoconstriction

front 49 Types of Arteries Arterioles	back 49 smallest type of artery Lead to capillary beds Control flow into capillary beds via vasodilation and vasoconstriction
front 50 Capillaries	back 50 smallest blood vessels – diameter from 8–10 µm A single layer of endothelial cells surrounded by a basement membrane Most important vessels red blood cells pass through single file Site-specific functions of capillaries Lungs: oxygen enters blood, carbon dioxide leaves Small intestines: receive digested nutrients Endocrine glands: pick up hormones Kidneys: removal of nitrogenous wastes
front 51 Capillary Permeability	back 51 Endothelial cells held together by tight junctions and desmosomes - block passage of small molecules But junctions are incomplete… Intercellular clefts: gaps of unjoined membrane Passageway for small molecules to enter and exit Fenestrations (pores): holes through endothelial cells Increases permeability
front 52 Types of capillaries- based on structure:	back 52 Continuous: most common, lack pores Found in most organs (skeletal muscle, lungs, skin, CNS) Fenestrated: large pores; increasedpermeability Occur where high exchange rates are needed (kidney, small intestines) Sinusoids: many pors and clefts; most permeable Occur in limited locations (liver, bone marrow, spleen)

front 53 1.Continuous capillaries	back 53
front 54 1.Fenestrated capillaries	back 54
front 55 1.Sinusoid capillaries (sinusoids)	back 55
front 56 The relationship of blood vessels to each other and to lymphatic vessels.	back 56

front 57 Capillary Beds	back 57 Network of capillaries running through most tissues Precapillary sphincters – regulate the flow of blood to tissues Composed of smooth muscle cells Regulated by local chemical conditions and vasomotor nerves
front 58 Veins	back 58 Venules: smallest veins Form when capillaries unite Postcapillary venules: smallest venules Venules join to form veins Veins Conduct blood from capillaries toward the heart Range in size from 0.5mm to 3 cm (venae cavae) Blood pressure is much lower than in arteries Walls are thinner lumen of a vein is larger Capacitance vessels i.e. blood reservoir Contain up to 65% of blood supply Valves Vascular sinus
front 59 Veins: Adaptations for Blood Flow Return	back 59 Large-diameter lumens offer little resistance Venous valves prevent backflow of blood Most abundant in veins of limbs Venous sinus Flattened veins with extremely thin walls E.g., coronary sinus of the heart and dural sinuses of the brain Collect blood
front 60 Circulatory Routes	back 60 Parallel blood flow Each organ receives its own supply of oxygenated blood Two basic routes for blood flow: Systemic circulation Pulmonary circulation

front 61 Systemic Circulation	back 61 Carries oxygen and nutrients to body tissues Removes carbon dioxide and other wastes and heat from the tissues All systemic arteries branch from the aorta All veins of systemic circulation drain into superior vena cava, inferior vena cava, or coronary sinus The blood vessels are organized according to regions of the body
front 62 Major Arteries	back 62
front 63 Major Veins of the Systemic Circulation	back 63
front 64 Physiology of Circulation Blood flow	back 64 volume of blood flowing through vessel, organ, or entire circulation in given period Measured as ml/min Equivalent to cardiac output (CO) for entire vascular system Relatively constant when at rest varies widely through individual organs, based on needs

front 65 Physiology of Circulation Blood pressure (BP)	back 65 blood pressure per unit area exerted on wall of blood vessel by blood Measured as millimeters of Mercury (mm Hg) Pressure gradient: blood moves from higher to lower pressure areas
front 66 Physiology of Circulation resistance	back 66 Opposition to flow; generally in systemic circulation Measure of amount of friction blood encounters with vessel walls
front 67 Physiology of Circulation Three important sources of resistance	back 67 Constant: 1.Blood viscosity ¨The "stickiness" of blood due to formed elements and plasma proteins; Increased viscosity = increased resistance 2.Total blood vessel length ¨Longer vessel =greater resistance encountered Variable: 3.Blood vessel diameter ¨Constantly changing; important influence on resistance ¨Smaller vessel diameter, high resistance ¨large vessel diameter, less resistance
front 68 Relationship Between Blood Flow, Blood Pressure, and Resistance	back 68 Blood flow(F) directly proportional to blood pressure gradient (change in P) If change in P increases , blood flow decreases Blood flow inversely proportional to resistance (R) If R increases , blood flow decreases Resistance more important in influencing local blood flow Easily changed by altering blood vessel diameter

front 69 Systemic Blood Pressure	back 69 Blood Flow Generated by pumping of heart Blood flow opposed by resistance -->Pressure Blood Pressure highest in the aorta and declines throughout the pathway (0 mm Hg in the right atrium) Arteries close to the heart are flexible and accommodate high volume
front 70 Arterial Blood Pressure	back 70 systolic pressure: pressure exerted in aorta during contraction of left ventricle (systole) Blood is forced into the aorta Averages 120 mm Hg in normal adult Diastolic pressure: lowest level of aortic pressure When blood is prevented from flowing back into the ventricles by the closed semilunar valve (diastole, relaxing of ventricle) 70–80 mm Hg