Rios Salado Bio202 Exam 1

i. intrinsic factors 1. Degree of stretch of cardiac muscle cells before they contract (Frank-Starling law of the heart) 2. Increased venous return distends (stretches) the ventricles and increases contraction force

Preload definition

lack obvious granules, nuclei are spherical or kidney shaped

Agranulocytes

(RBC antigens: B) (plasma antibodies: Anti-A) 1. Can receive B, O

B blood group

give rise to plasma cells, which produce antibodies that are released into the blood

B lymphocytes (B cells)

Bi-lobed nucleus, purplish-black cytoplasmic granules, 0.5-1% of WBC, release histamine and other mediators of inflammation; contain heparin, an anticoagulant

Basophil

thin, whitish layer of blood present at the erythrocyte-plasma junction

buffy coat

antimicrobial proteins in neutrophils

Defensins

a. Saline: replaces isotonic salt solution found in blood b. Multiple electrolyte solution: mimics the electrolyte composition of plasma

Describe fluids used to replace blood volume and the circumstances for their use

courses to the right side of the heart, where it gives rise to 2 branches

Right coronary artery

serves the myocardium of the lateral right side of the heart

Right marginal artery

forms most of th heart's anterior surface i. Pumps blood into the pulmonary trunk, which routes blood to the lungs where gas exchange occurs

Right ventricle structure and function

when the action potentials of the ventricular myocytes are in their plateau phases, the entire ventricular myocardium is depolarized

S-T segment

transport oxygen and carbon dioxide • biconcave (no nucleus, disc-shaped, salmon colored), diameter 7-8 um • Duration of development (D): 15 days • Life span (LS): 100-120 days • 4-6 million per mm^3 of blood

Erythrocytes

ride "horseback" on the thyroid gland

Parathyroid gland location

apex of heart to diaphragm, outside

Parietal Pericardium

comb-like ridges of muscle throughout most of the right atrium

Pectinate muscle

WBC metabolize oxygen to produce potent germ-killer oxidizing substances such as bleach and hydrogen peroxide

Respiratory burst

a. Pituitary, thyroid, parathyroid, adrenal, pineal glands b. Pancreas, gonads (ovaries and testes), placenta contain endocrine tissue

What are examples of endocrine organs?

represents the time between the beginning of atrial depolarization and ventricular depolarization (0.16-0.18 sec) • Longer interval may suggest a partial AV heart block caused by damage to the AV node

P-R interval

0.16s, time from the beginning of the atrial excitation to the beginning of the ventricular excitation, includes atrial depolarization and contraction as well as the passage of the depolarization wave through the rest of the conduction system

P-R/P-Q interval

Thyroid hormone (TH) Calcitonin

What are the hormones released by the thyroid gland?

i. Preventing blood loss. When a blood vessel is damaged, platelets and plasma proteins initiate clot formation, halting blood loss ii. Preventing infection. Drifting along in blood are antibodies, complement proteins, and white blood cells, all of which help defend the body against foreign invaders such as bacteria and viruses

What are the protective functions of blood?

i. Maintaining appropriate body temperature by absorbing and distributing heat throughout the body and to the skin surface to encourage heat loss ii. Maintaining normal pH in body tissues. Many blood proteins and other blood borne solutes act as buffers to prevent excessive or abrupt changes in blood pH that could jeopardize normal cell activities. Blood also acts as the reservoir for the body's "alkaline reserve" of biocarbonate ions iii. Maintaining adequate fluid volume in the circulatory system. Blood proteins prevent excessive fluid loss from the bloodstream into the tissue spaces. As a result, the fluid volume in the blood vessels remains ample to support efficient blood circulation to all parts of the body.

What are the regulatory functions of blood?

Glucagon Insulin

What hormones does the pancreas secrete?

the pressure that the ventricles must overcome to eject blood

Afterload

lack of EPO hormone that control red blood cell production

Renal anemia

(RBC antigens: A) (plasma antibodies: Anti-B) 1. Can receive A, O

A blood group

(RBC antigens: A and B) (plasma antibodies: none) 1. Can receive A, B, AB, O

AB blood group

based on the presence or absence of two Aggultinogens, type A and type B

ABO blood groups

prevents wide swings in water balance, helping the body avoid dehydration and water overload, substance that inhibits urine formation, stimulates kidney tubule cells to reabsorb water

ADH

a potent aggregating agent that causes more platelets to stick to the area and release their contents

ADP

60% of plasma protein, carrier to shuttle certain molecules through the circulation, is an important blood buffer, and is the major blood protein contributing to the plasma osmotic pressure (pressure that helps keep water in the bloodstream)

Albumin

how leukocytes move through tissue spaces (they form flowing cytoplasmic extensions that move them along)

Amoeboid motion

blood's oxygen-carrying capacity is too low to support normal metabolism i. Symptoms: fatigue, pale, short of breath, chilled ii. Causes: blood loss, not enough red blood cells produced, too many blood cells destroyed

Anemia

indicated a decreased oxygen-carrying capacity of blood that may result from a decrease in RBC number or size or a decreased hemoglobin content of the RBCs

Anemia definition

thoracic pain caused by a fleeting deficiency in blood delivery to the myocardium, may result from stress-induced spasms of the coronary arteries or from increased physical demands of the heart, the myocardial cells are weakened by the temporary lack of oxygen but do not die

Angina pectoris

when one hormone opposes the action of another (insulin lower blood glucose levels, which is antagonized by glucagon which raises blood glucose levels)

Antagonism

empty blood directly into the right atrium anteriorly

Anterior cardiac veins

earlike flaps of tissue projecting from the atrial chambers

Auricles

Antigens present on RBC membranes (A), Antibodies present in plasma (Anti-B)

Blood type A

Antigens present on RBC membranes (A and B), Antibodies present in plasma (none)

Blood type AB

Antigens present on RBC membranes (B), Antibodies present in plasma (Anti-A)

Blood type B

Antigens present of RBC membranes (Neither), Antibodies present in plasma (Anti-A and Anti-B)

Blood type O

splits from the right carotid artery and subclavian arteries, which supply the right side of the head and right forelimb

Brachiocephalic artery

heart rate below 60 beats/min • In athletes is good, it indicates an increased efficiency of cardiac functioning

Bradycardia

Depolarization opens up special Calcium channels in the plasma membrane, these slow Ca2+ channels allow entry of 10-20% of the Ca2+ needed for contraction, once inside, this influx of Ca2+ triggers Ca2+ sensitive channels in the SR to release bursts of Ca2+ that account for the other 80-90% of the Ca2+ needed for contraction

Briefly describe the events of excitation-contraction coupling in cardiac muscle cells

the amount of blood pumped out by each ventricle in one minute. (75 beats per minute)

Cardiac output

the difference between resting and maximal cardiac output (20-25L/min)

Cardiac reserve

substances that decrease contractility (H+, K+)

Negative inotropic agents

i. Vascular spasm 1. Smooth muscle contracts, causing vasoconstriction ii. Platelet plug formation 1. Injury to lining of vessel exposes collagen fibers; platelets adhere 2. Platelets release chemicals that make nearby platelets sticky; platelet plug forms iii. Coagulation 1. Fibrin forms a mesh that traps red blood cells and platelets, forming the clot

Process of hemostasis

when more than one hormone produces the same effects at the target cell and their combined effects are amplified (both glucagon and epinephrine cause the liver to release glucose to the blood)

Synergism

blood vessels that carry blood to and from all body tissues

Systemic circuit

periods of contraction

Systole

When ventricles contract

Systole def.

1. Pressure that must be overcome for ventricles to eject blood 2. Hypertension increases afterload, resulting in increased ESV and reduced SV

Afterload definition

red blood cell antigens (anything the body perceives as foreign and that generates an immune response) that promote agglutination

Agglutinogens

contain no visible cytoplasmic granules

Agranulocytes definition

follows the anterior interventricular septum and anterior walls of both ventricles

Anterior interventricular artery

cradles the anterior interventricular artery, marks the anterior position of the septum separating the right and left ventricles and continues on the posteroinferior surface as the posterior interventricular sulcus

Anterior interventricular sulcus

composed of glandular tissue, manufacturers and releases hormones

Anterior pituitary lobe

plasma proteins that react with RBCs bearing different antigens, causing them to be clumped, agglutinated, and eventually hemolyzed

Antibodies/agglutinins

glycoproteins on the outer surface of the RBC plasma membrane

Antigens/agglutinogens

where all systemic arteries of the body diverge to supply the body tissues

Aorta

results from destruction or inhibition of the red marrow by certain drugs and chemicals, ionizing radiation, or viruses

Aplastic anemia

defects in the intrinsic conduction system that cause irregular heart rhythms

Arrhythmias

an autonomic reflex initiated by increased venous return and increased atrial filling

Atrial (Bainbridge) reflex

smooth and lack the roughened appearance of the other regions of the atrial walls

Atrial walls near vena cavae are...

in the lower atrial septum at the junction of the atria and ventricles

Atrioventricular (AV) node

located between the atrial and ventricular chambers on each side, prevent backflow into the atria when the ventricles are contracting

Atrioventricular (AV) valves

a glistening white sheet of endothelium (squamous epithelium) resting on a thin connective tissue layer, lines the heart chambers and covers the fibrous skeleton of the valves

Endocardium

ductless glands, produce hormones, release hormones into the surrounding tissue fluid, and have a rich vascular and lymphatic drainage that receives their hormones, most cells in these glands are arranged in cords and branching networks (maximizes contact between cells and surrounding capillaries)

Endocrine glands

second great control system of the body that interacts with the nervous system to coordinate and integrate the activity of body cells

Endocrine system

the scientific study of hormones and the endocrine organ

Endocrinology

Bi-lobed nucleus, red cytoplasmic granules, 2-4% of all WBC, lead counterattack against parasitic worms, such as flat worms and round worms that are too large to be phagocytized, complex role in allergy and asthma

Eosinophil

visceral layer of the serous pericardium, often infiltrated with fat

Epicardium

released in response to stressors, mimics the sympathetic nervous system, response to relax 80%

Epinephrine

erythrocyte production

Erythropoiesis

a glycoprotein hormone stimulates the formation of erythrocytes. Things that trigger erythropoietin formation are: o Reduced numbers of red blood cells due to hemorrhage or excessive RBC destruction o Insufficient hemoglobin per RBC (as in iron deficiency) o Reduced availability of oxygen, as might occur at high altitudes during pneumonia

Erythropoietin

responsible for maturation of the reproductive organs and the appearance of the secondary sex characteristics of females at puberty, breast development, and the menstrual cycle

Estrogens and Progesterone (Ovaries)

sustains the fetus during pregnancy, secretes steroid and protein hormones that influence the course of pregnancy

Estrogens, Progesterone, human chorionin gonadotropin (hCG) Placenta

produce non-hormonal substances (sweat and saliva) and have ducts that carry these substances to a membrane surface

Exocrine glands

a. Negative feedback mechanism: reaction that causes a decrease in function (some internal or external stimulus triggers hormone secretion) b. Humoral stimuli: simplest endocrine control, secrete hormones in direct response to changing blood levels of certain critical ions and nutrients (insulin, Ca2+ levels, aldosterone) c. Neural stimuli: nerve fibers stimulate hormone release (stress: norepinephrine or epinephrine) d. Hormonal stimuli: release hormones in response to hormones produced by other endocrine organs (releasing and inhibiting hormones produced by the hypothalamus regulate the secretion of most anterior pituitary hormones)

Explain how hormone release is regulated

a. Microscopic studies of blood can reveal variations in the size and shape of erythrocytes that indicate iron deficiency or pernicious anemia b. Differential white blood cell count can determine if the eosinophil count is high (presence of parasitic infection or allergic response) c. Prothrombin time: assess the ability of blood to clot d. Comprehensive metabolic panel (CMP): measures various electrolytes, glucose, and markers of liver and kidney disorders e. Complete blood count (CBC): counts of different types of formed elements, the hematocrit, measurements of hemoglobin content, and size of red blood cells

Explain the diagnostic importance of blood testing

ovaries and testes; in females, stimulates ovarian follicle maturation and production of estrogens, in males, stimulates sperm production

Follicle-stimulating hormone (FSH)

cardiac muscle cells secrete atrial natriuretic peptide (ANP) inhibits sodium ion reabsorption and renin release (kidney), inhibits secretion of aldosterone; decreases blood pressure (adrenal cortex)

Hormonal function of the heart

Erythropoietin, stimulates production of red blood cells (red bone marrow)

Hormonal function of the kidney

Cholecalciferol, stimulates active transport of dietary calcium across cell membrane of small intestine (intestine)

Hormonal function of the skin

the degree to which cardiac muscle cells are stretched just before they contract, controls stroke volume

Preload

provide a rough index of the rate of red blood cell formation (should be between 1-2% of all erythrocytes)

Reticulocyte counts

i. C, D, E, c, and e antigen ii. 85% of Americans are Rh+ (contain D antigen) iii. Rh-

Rh blood groups

Thymulin, thymopoietins, thymosins, mostly act locally as paracrines; involved in T lymphocyte development and in immune responses

Hormonal function of the thymus

long-distance chemical signals that travel in blood or lymph throughout the body

Hormones

• Blood flows passively into atria then ventricles during diastole • AV valve flaps hang limply into the ventricular chambers and then are carried passively toward the atria by the accumulating blood • When systole happens and compresses the blood in their chambers, the intraventricular blood pressure rises, causing the valve flaps to be reflected superiorly, which closes the AV valves • The chordae tendineae pulled taut by the contracting papillary muscles, anchor the flaps in a closed position that prevents backflow into the atria during ventricular contraction • If unanchored, the flaps would blow upward into the atria rather like an umbrella being turned inside out by a strong wind

AV operation

outer adrenal gland, encapsulates the medulla and forms the bulk of the gland, glandular tissue derived from embryonic mesoderm

Adrenal cortex

found close to the kidney

Adrenal gland location

pyramid-shaped organs perched atop the kidneys, where they are enclosed in a fibrous capsule and a cushion of fat

Adrenal glands

knot of nervous tissue, part of sympathetic nervous system, one of two adrenal glands

Adrenal medulla

Adrenal cortex; promotes release of glucocorticoids and androgens

Adrenocorticotropic hormone (ACTH)

prevent blackflow into the atria when the ventricles contract, one located at each atrial-ventricular junction, attached to each AV valve are chordae tendineae (tiny white collagen cords), which anchor the cusps to the papillary muscles protruding from the ventricular walls

Atrioventricular valves

small, wrinkled, protruding appendages, which increase the atrial volume

Auricles

chemicals that exert their effects on the same cells that secrete them, short-distance signals (smooth muscle cells to contract smooth muscle cells)

Autocrines

heme group degraded into bilirubin, a yellow pigment is released into the blood and binds to albumin for transport

Bilirubin

arise from abnormalities that prevent normal clot formation

Bleeding disorders

a. Aging: connective tissue increases, vascularization decreases, number of hormone secreting cells decreases, GH levels decline (muscle atrophy), structural changes of adrenal glands and anterior pituitary b. Stress: drives up blood levels of cortisol and appears to contribute to hippocampal and memory deterioration, plasma levels of aldosterone decline, gonads (mostly ovaries) change with age, less estrogen produced), glucose tolerance declines, thyroid hormone synthesis decreases

Explain the effects of aging and stress on the endocrine system

located in the interventricular septum

Bundle branches

calcitonin is a polypeptide hormone released by the parafolicular or C cells of the thyroid gland in response to a rise in Ca2+ blood levels, targets the skeleton where it inhibits bone resorption and release of Ca2+ from the bony matrix and stimulates Ca2+ uptake and incorporation into bone matrix

Calcitonin

arranged in a spiral or figure-8-shaped bundles, when the heart contracts, its internal chambers become smaller, forcing the blood into the large arteries leaving the heart

Cardiac cells are...

all events assocated with the blood flow through the heart during one complete heartbeat

Cardiac cycle

i. Diastole: the chambers of the heart (atria and ventricles) are relaxed and filling up with blood from the veins. The atrioventricular valves (bicuspid on the left and tricuspid on the right) are open and the semilunar valves (pulmonary and aortic) are closed. This stage lasts for about 0.4 second. ii. Atrial systole: the atria contract and top up the ventricles. This takes about 0.1 second. iii. Ventricular systole: the ventricles contract and pump blood out of the heart into the arteries. During this stage the atrioventricular valves are closed and the semilunar valves are open. This takes about 0.3 second. The total cycle takes about 0.8 second while the subject is resting. This gives a heart rate of about 75 beats per minute.

Cardiac cycle stages

striated and contracts by the sliding filament mechanism, cardiac cells are short, fat, branched, and interconnected, 1-2 nuclei per fiber, tissue matrix (endomysium) containing numerous capillaries, intercalated discs: desmosomes (prevent cells from separating during contraction) and gap junctions (allow ions to pass from cell to cell to, transmit current across the entire heart), 25-35% volume of mitcochondria, pace-maker cells (self-excitable), contracts as 1 unit, longer absolute refractory period, only aerobic respiration

Cardiac muscle

dense network of tissue fibers that reinforce the myocardium and anchors the cardiac muscle fibers so that the valves don't stretch out after continual use (elastic)

Cardiac skeleton

venous blood is collected by these after passing through the capillary beds of the myocardium, path follows the coronary arteries

Cardiac veins

projects to sympathetic neurons in the T1-T5 level of the spinal cord, preganglionic neurons synapse with postganglionic neurons in the cervical and upper thoracic trunk, postganglionic nerve fibers run trough the cardiac plexus to innervate the SA and AV nodes, heart muscle, and coronary arteries

Cardioacceleratory center

sends impulses to the parasympathetic dorsal vagus nucleus in the medulla, which sends inhibitory impulses to the heart via branches of the vagus nerves

Cardioinhibitory center

Coronary atherosclerosis Persistent high blood pressure Multiple myocardial infarctions Dilated cardiomyopathy (DCM)

Causes of congestive heart failure

tiny white collagenic cords, anchor the cusps to the ventricular walls (heart strings)

Chordae tendineae

supplies the left atrium and the posterior walls of the left ventricle

Circumflex artery

Lymphocyte Monocyte

Classes of Agranulocytes

Neutrophil Eosinophil Basophil

Classes of Granulocytes

a. Exerts the most important extrinsic controls affecting heart rate When emotional or physical stressors, such as fright, anxiety, or exercise, activate the sympathetic nervous system, sympathetic nerve fibers release norepinephrine at their cardiac synapses. The heart responds by beating faster.

Explain the role of the autonomic nervous system in regulating cardiac output.

premature contraction

Extrasystole

i. Phase 1: activated platelets display negatively charged phosphatidylserine, intermediate steps of each pathway cascade toward a common intermediate (Factor X), when factor X is activated it complexes with calcium ions and factor V on a phospholipid surface to form prothrombin activator, clot forms in 10-15 seconds ii. Phase 2: Prothrombin activator catalyzes the conversion of a plasma protein, prothrombin, into the active enzyme thrombin iii. Phase 3: Thrombin catalyzes the transformation of fibrinogen into fibrin. Fibrin molecules join together to form strands. Fibrin strands glue platelets together. Fibrin makes blood into gel to inhibit formed elements from passing through it, in the presence of calcium ions thrombin activates factor XIII (cross-linking enzyme) binds fibrin strands together to form a mesh, seals hole until blood vessel is repaired

Clot formation process

substances that transform blood from a liquid to a gel

Clotting factors/procagulants

the heart is such an inefficient pump that blood circulation is inadequate to meet tissue needs

Congestive heart failure (CHF)

i. Depolarization: due to Na+ influx through fast voltage-gated Na+ channels. A positive feedback cycle rapidly opens many Na+ channels, reversing the membrane potential. Channel inactivation ends this phase. ii. Plateau phase: due to Ca2+ influx through slow Ca2+ channels. This keeps the cell depolarized because most K+ channels are closed. iii. Repolarization: due to Ca2+ channels inactivation and K+ channels opening. This allows K+ efflux, which brings the membrane potential back to its resting voltage.

Contractile cells

the contractile strength achieved at a given muscle length, independent of muscle stretch and EDV

Contractility

extrinsic factors called inotropic agents (mscell) 1. Contractile strength at a given muscle length, independent of muscle stretch and EDV 2. Affected by ion exchange across membranes of heart ms cells 3. Increased contractility = increased SV—due to ↑cytoplasmiccalcium ions 4. + inotropicagents ↑contractility/-agents ↓contractility

Contractility definition

fatty buildup in coronary arteries that blocks oxygen delivery to cardiac cells

Coronary athersclerosis

the functional blood supply of the heart, the shortest circulation in the body

Coronary circulation

Left coronary artery Right coronary artery

Coronary circulation is broken into 2 arteries...

where veins join to form an enlarged vessel, empties blood into the right atrium

Coronary sinus

just below the inferior vena caval opening, returns venous blood of the coronary circulation to the right atrium

Coronary sinus location

atrioventricular groove, encircles the junction of the atria and ventricles like a crown

Coronary sulcus

adrenal cortex synthesizes over two dozen steroid hormones

Corticosteroids

a. Leukocytes arise from ancestral stem cells called hematopoietic stem cells b. Granular leukocytes develop via a sequence involving myeloblasts c. Monocytes, like granular leukocytes, are progeny of the myeloid stem cell and share a common precursor with neutrophils d. Only lymphocytes arise via the lymphoid stem cell line

Describe how leukocytes are produced

o A cone-shaped organ approximately the size of a fist, is located within the mediastinum, or medial cavity, of the thorax o Flanked laterally by the lungs, posteriorly by the vertebral column, and anteriorly by the sternum o Pointed Apex extends slightly to the left and rests on the diaphragm, approximately at the level of the 5th intercostal space o The base, from which the great vessels emerge, lies beneath the second rib and points toward the right shoulder, the right ventricle of the heart forms most of its anterior surface

Describe location of the heart

a. Structural pituitary gland located on sella turcica and infundibulum connects pituitary gland to the hypothalamus (above it) maintains connection through nerve bundles called the hypothalamic-hypophyseal tract b. Functional: action potentials travel down the axons of hypothalamic neurons, causing hormone release from their axon terminals in the posterior pituitary, hypothalamic hormones released into special blood vessels (the hypophyseal portal system) control the release of anterior pituitary hormones

Describe structural and functional relationships between the hypothalamus and pituitary gland

Made up of red heme pigment bound to the protein globin (four polypeptide chains-two alpha and two beta-each binding a ring-like heme group) Each heme group bears an atom of ion in its center

Describe the chemical composition of hemoglobin (protein that makes red blood cells red)

a. Whole blood is made up of living blood cells (formed elements) and a nonliving fluid matrix called plasma. Red blood cells that transport oxygen are called erythrocytes and make up 45% of the total volume of blood. Leukocytes (white blood cells) make up 1% of blood volume and plasma makes up 55% of blood volume. Characteristics of blood are: i. Metallic taste ii. Scarlet (oxygen-rich) Dark-red (oxygen-poor) iii. pH 7.35-7.45 iv. Blood is more dense than water and about 5X more viscous due to formed elements v. 8% of body weight b. Blood lacks the collagen and elastic fibers typical of other connective tissues, but dissolved fibrous proteins become visible as fibrin stands during blood clotting.

Describe the composition and physical characteristics of whole blood. Explain why it is classified as a connective tissue.

a. Size: size of a fist b. Shape: hollow cone-shaped mass, 250-350 g c. Location: enclosed within the mediastinum d. Orientation: medial cavity of the thorax, lies 2/3 to the left of the midsternal line

Describe the size, shape, location, and orientation of the heart in the thorax

a condition of rapid uncoordinated heart contractions which makes the heart useless as a pump

Fibrillation condition

a. Structure: small cells, flattened discs with depressed centers, lack a nucleus, has no organelles i. Its small size and shape provide a huge surface area relative to volume. The disc shape is ideally suited for gas exchange because no point within the cytoplasm is far from the surface ii. Discounting water content, an erythrocyte is over 97% hemoglobin, the molecule that binds to and transports respiratory gases iii. Because erythrocytes lack mitochondria and generate ATP by anaerobic mechanisms, they do not consume any of the oxygen they carry, making them efficient oxygen transporters b. Function: picks up oxygen in the capillaries of the lungs and releases it to tissue cells across other capillaries throughout the body. It also transports 20% of the carbon dioxide released by tissue cells back to the lungs

Describe the structure, function, and production of erythrocytes

Target cells First Mechanism: Cyclic AMP Signaling Mechanism Second Mechanism: PIP2- Calcium Signaling Mechanism

Describe the two major mechanisms by which hormones bring about their effect on their target tissues

a. Embryonic heart chambers i. Sinus venous ii. Atrium iii. Ventricle iv. Bulbus cordis b. Fetal heart structures that bypass pulmonary circulation i. Foramen ovale connects the two atria ii. Ductus arteriosus connects the pulmonary trunk and the aorta c. Congenital heart defects i. Lead to mixing of systemic and pulmonary blood ii. Involve narrowed valves or vessels that increase the workload on the heart

Developmental aspects of the heart

white blood cells are able to slip out of the capillary blood vessels

Diapedesis

period of ventricular filling

Diastole

periods of relaxation

Diastole

100 WBCs are counted and classified according to type, routine in a physical examination and in diagnosing illness, any abnormality or signification elevation in percentages of WBC types may indicate a problem or the source of pathology

Differential white blood cell

ventricles stretch and become flabby and the myocardium deteriorates, drug toxicity or chornic inflammation may be involved

Dilated cardiomyopathy (DCM)

o Rh-negative persons who receive transfusions of Rh-positive blood become sensitized by the Rh antigens of the donor's RBCs, and their systems begin to produce anti-Rh antibodies. On subsequent exposures to Rh-positive blood, typical transfusion reactions occur, resulting in the clumping and hemolysis of the donor blood cells.

Discuss the reason for transfusion reactions

characteristics of both types of disorders, involved both widespread clotting and severe bleeding, clotting occurs in intact blood vessels and the residual blood becomes unable to clot i. Complication of pregnancy ii. Septicemia iii. Incomplete blood transfusions

Disseminated intravascular coagulation (DIC)

prolonged exposure to high hormone concentrations can decrease the number of receptors for that hormone

Down-regulation

lung bypass between the pulmonary trunk and the aorta

Ductus arteriosus

in the fetus, the ductus arteriosus allows blood to pass directly from the left pulmonary trunk to the aorta, bypassing the nonfunctional fetal lungs

Ductus arteriosus location

an abnormal pacemaker

Ectopic focus

i. Hyposecretion: rare ii. Hypersecretion: Cushing's disease

Effects of abnormal secretion of ACTH

i. Effects of hyposecretion (less): diabetes insipidus ii. Effects of hypersecretion (more): syndrome inappropriate of ADH secretion (SIADH)

Effects of abnormal secretion of ADH

i. Hyposecretion: failure of sexual maturation ii. Hypersecretion: no important effects

Effects of abnormal secretion of FSH

i. Effects of Hyposecretion: pituitary dwarfism in children ii. Effects of Hypersecretion: gigantism in children; acromegaly in adults

Effects of abnormal secretion of GH

i. Hyposecretion: poor milk production in nursing women ii. Hypersecretion: inappropriate milk production, cessation of menses in females, impotence in males

Effects of abnormal secretion of PL

i. Hypersecretion: Cretinism in children, myxedema in adults ii. Hyposecretion: hyperthyroidism; effects similar to those of Graves' disease, in which antibodies mimic TSH

Effects of abnormal secretion of TSH

a graphic record of heart activity, composite of all the action potentials generated by nodal and contractile cells at a give time

Electrocardiogram (ECG)

the graphic recording of the electrical changes (depolarization followed by repolarization) occurring during the cardiac cycle

Electrocardiogram (ECG)

if a thrombus breaks away from the vessel wall and floats away in the bloodstream, if it gets stuck in a narrow blood vessel (embolism) it can obstruct the vessel and lead to the body not obtaining enough oxygen or a stroke 1. Aspirin, heparin and warfarin are used to prevent undesirable clotting

Embolus (Thromboembolic disorders)

the amount of blood that collects in a ventricle during diastole (120ml)

End diastolic volume (EDV)

the volume of blood remaining in a ventricle after it has contracted (50 ml)

End systolic volume (ESV)

i. Tissue factor is requires is outside of the blood ii. Triggered by exposing blood to a factor found in tissues underneath the damaged endothelium (Tissue factor or factor III) iii. Faster because it bypasses several steps of the intrinsic pathway. In severe trauma, it can form a clot in 15 seconds

Extrinsic pathway of blood clot formation

i. Chronotropic factors: + chronotropicfactors ↑HR, -chronotropicfactors ↓HR ii. Chemical regulation 1. Hormones: epinephrine/norepinephrine, thyroxine (thyroid hormone) 2. Ionic balance: intra-and extracellular (Ca2+ and K+) iii. ANS controls: most important extrinsic controls affecting HR 1. Sympathetic ns stimulates pacemaker cells which will ↑HR 2. Atrial (Bainbridge) reflex: a sympathetic reflex initiated by increased venous return. Blood puts stretch on atrial walls and stimulates SA node as well as atrial stretch receptors which activates sympathetic reflexes 3. Parasympathetic ns inhibits pacemaker cells which ↓HR 4. Vagal tone: heart at rest, dominant influence is inhibitory

Factors that affect HR (time)

i. Platelet-derived growth factor (PDGF): released by platelets to stimulate smooth muscle cells and fibroblasts to divide and rebuild the vessel wall ii. Fibrinolysis: removes unneeded clots when healing has occurred iii. Plasmin: a fibrin digesting enzyme iv. Swift removing of clotting factors v. Inhibition of activated clotting factors

Factors that limit clot formation

stores iron inside as protein-iron complexes

Ferritin and hemosiderin

a condition of rapid irregular or out-of-phase contractions in which control of heart rhythm is taken away from the SA node by rapid activity in other heart regions

Fibrillation

a. Thyroglobulin is synthesized and discharged into the follicle lumen b. Iodide is trapped (once trapped inside the follicular cell, iodide moves into the follicle lumen by facilitated diffusion) c. Iodide is oxidized to iodine d. Iodine is attached to tyrosine (attachment of one iodine to tyrosine produces MIT, monoiodotyrosine and attachment of two iodines produces diiodotyrosine, DIT) e. Iodinated tyrosines are linked together to form T3 and T4 (two linked DITs = T4, MIT + DIT = T3) f. Thyroglobulin colloid is endocytosed (to secrete hormones, the follicular cells must reclaim iodinated thyroglobulin by endocytosis and combine the vesicles with lysosomes) g. Lysosomal enzymes cleave T4 and T3 from thyroglobulin and the hormones diffuse from the follicular cell into the bloodstream

Follow the process of thyroxine formation and release

connects two atria and allows blood entering the right heart to bypass the pulmonary circuit and the nonfunctional fetal lungs

Foramen ovale

opening in the fetal heart, allow blood to pass from the right to the left atrium, bypassing the fetal lungs

Foramen ovale location

erythrocytes, leukocytes, and platelets

Formed elements

(45% of whole blood)

Formed elements %

oval depression in the Interatrial septum, marks the opening in the fetal heart

Fossa ovalis

the higher the preload, the higher the stroke volume

Frank Starling Law of the Heart

form a mobile army that helps protect the body from damage by bacteria, viruses, parasites, toxins, and tumor cells

Function of leukocytes

essential for clotting process that occurs in plasma when blood vessels are ruptured or their lining is injured

Function of platelets

cardiac muscle cells are electrically connected by connected by gap junctions, the entire myocardium behaves as single unit

Functional syncytium

29 amino acid polypeptide, potent hyperglycemic agent, target: liver i. Breakdown of glycogen into glucose, synthesis of glucose from lactic acid and from non-carbohydrate molecules, release of glucose to the blood by liver cells, causing blood glucose levels to rise ii. Lower blood levels of amino acids as the liver cells sequester these molecules to make new glucose molecules iii. Alpha cells prompt glucagon secretion

Glucagon

influence the energy metabolism of most body cells and help us resist stressors, produce metabolic hormones (middle layer: Zona fasciculata) i. Examples: Cortisol (hydrocortisone), cortisone, corticosterone ii. Negative feedback regulates secretion, Cortisol release is promoted by ACTH iii. Affected by stress

Glucocorticoids

weak male sex hormones converted into testosterone or estrogens, produce adrenal sex hormones (inner layer: zona reticularis) i. Stimulated by ACTH; mechanism of inhibition incompletely understood, but feedback inhibition not seen ii. Insignificant effects in males; contributes to female libido, development of pubic and axillary hair in females, source of estrogens after menopause

Gonadocorticoids

regulate the function of the gonads (ovaries and testes)

Gonadotropins

granules stain differently with Wright's stain, have lobed nuclei

Granulocyte definition

contain obvious membrane-bound cytoplasmic granules, all roughly spherical in shape, large, short-lived

Granulocytes

1 of 3 tributaries of the coronary sinus, in the anterior interventricular sulcus

Great cardiac vein

liver, muscle, bone, cartilage, and other tissues: anabolic hormone; stimulates somatic growth; mobilizes fats; spares glucose, growth promoting effects mediated by IGFs

Growth hormone(GH)

inhibits growth hormone release

Growth hormone-inhibits hormone (GHIH)

stimulates growth hormone release

Growth hormone-releasing hormone (GHRH)

the length of time for a hormone's blood level to decrease by half, varies from a fraction of a minute to a week (water-soluble hormones have the shortest half-lives

Half-life

no more than the transport system pump (blood vessels= delivery routes)

Heart

abnormal heart sounds most often indicative of valve problems

Heart murmurs

red blood cell formation

Heatopoiesis

blood fraction

Hematocrit

male: 47.0 ± 7 and female: 42.0 ± 5, routinely determined when anemia is suspected, Centrifuging whole blood spins the formed elements to the bottom of the tube, with plasma forming the top layer

Hematocrit level

Male: 13-18 g of hemoglobin per 100ml of blood and female: 12-16 g of hemoglobin per 100ml of blood,

Hemoglobin determination

erythrocytes rupture prematurely due to certain bacterial and parasitic infections

Hemolytic anemia

hereditary bleeding disorders that result from a deficiency in factor VIII (Hemophilia A), deficiency in factor IX (Hemophilia B), lack of factor XI (hemophilia C) 1. Joints become severely disabled and painful, minor tissue trauma causes severe and prolonged bleeding

Hemophilia (bleeding disorder)

stops bleeding

Hemostasis

Osteocalcin, increases insulin production and insulin sensitivity

Hormonal function of bone

i. Leptin: tells your body how much stored energy (as fat) you have 1. Brain, suppresses appetite, increases energy expenditure ii. Resistin: insulin antagonist (fat, muscle, liver) iii. Adiponectin: enhances sensitivity to insulin (fat, muscle, liver)

Hormonal function of the adipose tissue

a. Amino-acid based: hormones are water soluble and cannot cross the plasma membrane (epinephrine, thyroxine, peptides, protein) b. Steroids: hormones synthesized from cholesterol, lipid soluble and can cross the plasma membrane (only gonadal and adrenocortical hormones are steroids)

How are hormones classified chemically?

o SA node provides stimulus for contraction, pacemaker because it sets the rate of depolarization for the heart as a whole o The impulse spreads throughout the atria to the AV node, electrical wave immediately followed by atrial contraction o At the AV node the impulse is delayed for 0.1s so the atria can complete their contraction o Impulse passes through the AV bundle, the right and left bundle branches, and the Purkinje fibers, resulting in ventricular contraction o The nodal system increases the rate of heart depolarization and synchronizes heart activity o Atria and ventricles are separated from one another by a region of electrically inert connective tissue, so the depolarization wave can be transmitted to the ventricles only via the tract between the AV node and the AV bundle

How are impulses initiated and conducted through the heart

Individuals whose RBCs carry the Rh antigen are Rh-positive, those who don't are Rh-negative

How do you classify Rh+ and Rh-

a. Blood levels of the hormone b. Relative numbers of receptors for that hormone on or in the target cells c. Affinity (strength) of the binding between the hormone and the receptor

Identify factors that influence activation of a target cell

when the liver is unable to synthesize its usual supply of clotting factors, usually caused from Vitamin K deficiency, hepatitis, cirrhosis, and if fat absorption is impaired

Impaired liver function (bleeding disorder)

highly contagious viral disease most often seen in young adults, lymphocytes are numerous and are large and atypical and are commonly misidentified as monocytes i. Symptoms: tired, achy, chronic sore throat, low grade fever

Infectious Mononucleosis

small 51 amino acid protein consisting of two amino acid chains linked by disulfide bonds, lowers blood glucose levels, promotes protein synthesis and fat storage, participates in neuronal development, feeding behavior, and learning and memory i. Circulating insulin lowers blood glucose levels by: 1. Enhances membrane transport of glucose into most body cells, especially muscle and fat cells 2. Inhibits the breakdown of glycogen to glucose 3. Inhibits the conversion of amino acids or fats to glucose, counter any metabolic activity that would increase plasma levels of glucose

Insulin

growth-promoting proteins

Insulin-like growth factors (IGFs)

internal partition that divides the heart longitudinally (separates atria)

Interatrial septum

the septum that divides the heart longitudinally depending on which chambers it separates

Interatrial/Interventricular septum

branching cells and the areas where the cells interdigitate, allow for close coordination of heart activity

Intercalated discs

o ECG is a record of voltage and time o Measures electrical events in large cardiac muscle tissue not nodal tissue o P wave: start of P deflection to return to isoelectric line o T wave: start of T deflection to return to isoelectric line o QRS complex: (0.08 sec) start of Q deflection to S return to isoelectric line • Longer may indicate a right or left bundle branch block in which one ventricle is contracting later than the other

Interpret the ECG in terms of depolarization and repolarization events occurring in the myocardium and to identify the P, QRS, and T waves on an ECG recording.

separates the ventricles

Interventricular septum

i. Factors needed for clotting are found within the blood ii. Triggered by negatively charged surfaces such as activated platelets, collagen, or glass iii. Slower because it has many intermediate steps

Intrinsic pathway of clot formation

consists of specialized noncontractile myocardial tissue, ensure that heart muscle depolarizes in an orderly and sequential manner (from atria to ventricles) and that the heart beats as a coordinated unit

Intrinsic/Nodal System

inadequate intake of iron-containing foods or hemorrhagic anemia

Iron deficiency anemia

pace set by AV node, 40-60 beats per minute

Junctional rhythm

mostly smooth pectinate muscles are only found in auricle, internal septum has fossa ovalis i. Four pulmonary veins enter the left atrium, which makes up most of the heart's base, these veins transport blood from the lungs back to the heart

Left atrium structure and function

runs toward the left side of the heart and then divides into two branches

Left coronary artery

anterior interventricular artery Circumflex artery

Left coronary artery is broken up into...

dominates posteroinferior surface i. Both ventricles have irregular ridges of muscle (trabeculeae carneae) that mark the internal walls of the ventricular chambers, and papillary muscles that play a role in valve function ii. Larger than atrial walls iii. Ejects blood into the aorta, the largest artery in the body

Left ventricle structure and function

a decrease in the WBC number below 4000 per mm^3 of blood, may indicate typhoid fever, measles, infectious hepatitis or cirrhosis, tuberculosis, or excessive antibiotic or X-ray therapy

Leucopenia

a malignant disorder of the lymphoid tissues characterized by uncontrolled proliferation of abnormal WBCs accompanied by a reduction in the number of RBCs and platelets, detectable by total WBC count and differential WBC count

Leukemia definition

overproduction of abnormal white blood cells, cancerous leukocytes fill the red bone marrow and immature WBC flood into the bloodstream, they are nonfunctional and can't defend the body i. Symptoms: severe anemia and bleeding problems, fever, weight loss, bone pain

Leukemias

white blood cells

Leukocyte

spherical, nucleated cells, 4800-10,800 per mm^3 of blood

Leukocytes

Granulocytes Agranuloctytes

Leukocytes are broken up into the classes...

white blood cell count over 11,000 cells (normal response to infection in the body)

Leukocytosis

an abnormally high WBC count, could indicate a bacterial or viral infection, metabolic disease, hemorrhage, or poisoning by drugs or chemicals

Leukocytosis definition

production of white blood cells

Leukopoiesis

Ovaries and testes: in females, triggers ovulation and stimulates ovarian production of estrogens and progesterone; in males, promotes testosterone production

Leutinizing hormone (LH)

a cordlike remnant of the ductus arteriosus

Ligamentum arteriosum

Permissiveness Synergism Antagonism

List 3 kinds of interaction of different hormones acting of the same target cell

Never Let Monkeys Eat Bananas (Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils)

List of Leukocytes most abundant to least abundant

small with large spherical nucleus, thin rim of pale blue cytoplasm, 25% of WBC, mount immune response by direct cell attack or via antibodies

Lymphocyte

o Blood is classified as a connective tissue, substances transported by blood are nutrients (glucose, fatty acids, amino acids, vitamins), waste products of metabolism (urea, uric acid), respiratory gases (O2 and CO2), hormones

Major components of blood

1. AV valves open, atrial pressure > ventricular pressure a. Blood returning to the heart fills atria, pressing against the AV valves. The increased pressure forces AV valves open. b. As ventricles fill, AV valve flaps hang limply into ventricles. c. Atria contract, forcing additional blood into ventricles. 2. AV valves closed, atrial pressure < ventricle pressure a. Ventricles contract, forcing blood against AV valve cusps. b. AV valves close. c. Papillary muscles contract and chordae tendineae tighten, preventing valve flaps from everting into atria.

Mechanism of Atrioventricular valve operation

a. Semilunar valves open i. As ventricles contract and intraventricular pressure rises, blood is pushed up against semilunar valves, forcing them open. b. Semilunar valves closed i. As ventricles relax and intraventricular pressure falls, blood flows back from arteries, filling the cusps of semilunar valves and forcing them to close

Mechanism of Semilunar valve operation

an amine hormone derived from serotonin

Melatonin

1 of 3 tributaries of the coronary sinus, in the posterior interventricular sulcus

Middle cardiac vein

regulate the electrolyte concentrations in extracellular fluids (Na+ and K+), hormones that help control the balance of minerals and water in blood (outer layer: Zona glomerulosa) i. Example: Aldosterone 1. Stimulates Na+ reabsorption (increasing blood volume and blood pressure) 2. Causes K+ secretion into the tubules for elimination from the body ii. Renin-Angiotensin Aldosterone Mechanism: triggers aldosterone release and raises blood pressure

Mineralcorticoids

left atrioventricular valve, consists of two cusps of endocardium

Mitral valve

left AV valve, 2 cusps, resembles tall, pointed hat, aka bicuspid valve

Mitral/Bicuspid valve

a bundle of cardiac muscle fibers connecting the interventricular septum to anterior papillary muscles, contains a branch of the atrioventricular bundle and helps coordinate contraction of the ventricle

Moderator band

kidney-shaped nucleus, abundant pale blue cytoplasm, 3-8% of WBC, phagocytosis; develop into macrophages (actively phagocytic and crucial in the body's defense against viruses, bacterial parasites, and chronic infections) in the tissues

Monocyte

multiple heart attacks depresses pumping efficiency because scar tissue replaces the dead heart cells

Multiple myocardial infarctions

prolonged coronary blockage where myocardial cells do die, damage to the left ventricle is the most serious

Myocardial infraction (MI)/heart attack

composed mainly of muscle and forms the bulk of the heart, muscle bundles contract the heart

Myocardium

fibrous skeleton of the heart, cardiac muscles, dense fibrous connective tissue network

Myocardium

a. Sinoatrial node (pacemaker) generates impulses b. The impulses pause (0.1s) at the atrioventricular node (AV node) c. The atrioventricular bundle connects the atria to the ventricles d. The bundle branches conduct the impulses through the interventricular septum e. The subendocardial conducting network/Purkinje fibers depolarizes the contractile cells of both ventricles

Name the components of the conduction system of the heart, and trace the conduction pathway

a. Pericardium: double-walled sac that the heart is enclosed in i. Fibrous pericardium: superficial layer, tough dense connective tissue 1. Protects the heart 2. Anchors it to surrounding structures 3. Prevents overfilling of the heart with blood ii. Serous pericardium: thin slipper, 2 layers 1. Parietal Layer: lines the internal surface of the fibrous pericardium 2. Visceral layer: external heart surface b. Pericardial cavity: space between parietal and visceral layer that contains serous fluid

Name the coverings of the heart

neural functioning plus releases hormones (hypothalamus)

Neuroendocrine organ

Multi-lobed nucleus, pale red and blue cytoplasmic granules, 50-70% of WBC population, 2X size of erythrocytes, attracted to sites of inflammation, partial to bacteria and fungi

Neutrophil

response to stress 20% • Release stimulated by the nervous system

Norepinephrine

Two sounds (lub-dup) associated with closing of heart valves. First sound occurs as AV valves close and signifies beginning of systole. Second sound occurs when SL valves close at the beginning of ventricular diastole

Normal heart sounds

(RBC antigens: none) (plasma antibodies: Anti-A and Anti-B) 1. Can receive O

O blood group

The heart is a very important muscle in our body that keeps blood flowing to our tissues to keep them nourished with oxygen and help transport carbon dioxide waste to the lungs for gas exchange. The heart uses electrical impulses from specialized nodes to trigger the cardiac muscles to contract, which in turn leads to the continuous pumping function of the heart. The specialized nodes of the heart are the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node is located in the right atrium and is inferior to the superior vena cava entrance. The SA node is the pacemaker of the heart and sets the rate of depolarization that begins the electrical signal that tells the heart to contract. The AV node is located in the lower atrial septum at the junction of the atria and ventricles. The AV node's function is to delay the contraction of the ventricles until the atrial contraction is complete for 0.1s. The sequence of impulse generation in the heart start off at the SA node. The SA node generates an electrical impulse which begins atrial excitation. The signal is then passed to the AV node where the signal is delayed until the atria have finished their contraction. Next, the impulse is passed to Atrioventricular (AV) bundle located superior interventricular septum and is then passed through the left and right bundle branches located in the interventricular septum, which stimulates ventricular excitation. When the impulse reaches the Purkinje fibers in the left and right ventricles, the ventricles contract. The heart contains three layers of muscles called the epicardium, myocardium, and endocardium. The epicardium is the outer muscle of the heart, the myocardium is the middle layer of muscles, and the endocardium is the inner layer of cardiac muscle that actually comes into contact with the blood in the heart. The heart is composed of myocardial muscle cells that make up the walls of the atria and the ventricles that have contractile and elastic properties that aid in cardiac contraction. The contractile properties of the myocardial cells help the heart stretch and allow the chambers to fill with blood. The elastic property of the myocardial cells allow the heart to remain intact and strong after stretching. Due to the fact that the heart must go through constant strain during contraction, it must be able to bounce back from stretching. The heart also contains papillary muscles, which help anchor the chordae tendinae to the walls of the heart. The chordae tendinae are strings of white collagen fibers that are attached to tricuspid and mitral valve to keep them from being blown back into the atria during contraction. Cardiac muscle also contains intercalated discs, which allow an electrical impulse to sent through the whole muscle through gap junctions and allow the heart to contract as one unit. Also, the left side of the heart contains more muscle tissue, because the left ventricle has to use more force to push blood up and out of the heart to the body tissues. The heart is a complex organ with many structures and specialized muscle fibers that help aid in its contraction. The heart is composed of two atria, the right and the left atrium, and two ventricles, the right and the left ventricles. The heart is also composed of four valves, two valves known as the atrioventricular valves that separate the corresponding atria and ventricles and two valves that are known as the pulmonary and aortic semilunar valves that guard the bases of the two large arteries leaving the ventricular chambers. The right atrium and right ventricle are separated by the Tricuspid valve that helps prevent blood from back-flowing into the atria when the ventricles are contracting. The left atrium and left ventricle are separated by the Mitral/Bicuspid valve, which helps prevent backflow into the atria during ventricular contraction. The pulmonary semilunar valve is between the right ventricle and pulmonary artery and the aortic semilunar valve is between the left ventricle and the aorta. The semilunar valves help keep arterial blood from reentering the heart. The cycle of contraction and blood flow begins with deoxygenated blood entering from the superior and inferior vena cava and into the right atrium, through the tricuspid valve, and to the right ventricle. At this point the heart is in diastole, which means the heart is relaxed and not contracting. When the right ventricle is stretched and filled with its full capacity of blood the SA node sends an impulse to the AV node, then to the AV bundle, next to the bundle branches, and finally to the Purkinje fibers to contract the right ventricle and push the deoxygenated blood up through the pulmonary semilunar valve and out the pulmonary trunk and the pulmonary artery to the lungs for gas exchange. At the lungs carbon dioxide is exchanged for oxygen, which concludes the pulmonary circuit. Once the blood is oxygen rich it enters the heart through the pulmonary veins to the left atrium, through the mitral valve and into the left ventricle. Once the left ventricle is filled to its maximum capacity the heart goes from diastole to systole, which is when the heart enters contraction. The SA node sends an impulse to the AV node, then to the AV bundle, next to the bundle branches, and finally to the Purkinje fibers to push the oxygenated blood out of the left ventricle through the aortic semilunar valve and the aorta to deliver oxygen-rich blood to the body tissues. This concludes the systemic circuit. The information of the conduction system and the blood flow of the heart as well as the heart's identifying structures will definitely be useful information to me when I become a Registered Nurse. For example, the results of an electrocardiagram or an ECG test will help me determine my patient's heart rate. From there, I can determine if they have a regular rhythm and their heart is depolarizing and repolarizing normally, which is about 70 beats per minute for an adult. If I noticed that there was a significant increase, such as over 100 beats per minute I would be able to identify my patient with Tachycardia. If my patient had a significantly lower heart rate than average I would diagnose them with Bradycardia, which is a heart rate lower than 60 beats per minute. However, if I inquired with the patient and asked preliminary questions and discovered that the patient was a high-performing athlete, I would not be concerned with the patient's heart rate. I would not be concerned because a lower heart rate in athletes is common because it is a sign of increased cardiac efficiency and there would be no cause for concern or methods of treatment needed.

On Exam 1 you will be presented with an essay question. The essay topic is cardiac impulse generation. You will be asked to compose an essay about the cardiac impulse generation and conduction. a. A discussion cardiac conduction should begin with description of the specialized nodes (autorhythmic character) of the heart and their locations. b. The sequence should be discussed as well as coordinating location in the heart. c. The actual innervation of the cardiac muscle and appropriate structures should be considered. d. Correlation between the stages of impulse should be related to the flow of blood, contraction of the chambers and open and closing of the valves.

c. Age - Fetus has fastest HR (140-160 beats/min) d. Gender - Females faster than males F:(72-80 beats/min) M:(64-72 beats/min) e. Exercise - Increases HR (40-60 beats/min) f. Body temperature - Increases with increased temperature

Other factors that affect heart rate

found in the pelvic cavity of the female, concerned with ova and female hormone production

Ovaries location

stimulates uterine contractions; initiates labor, initiates milk ejection

Oxytocin

lasts 0.08s and results from movement of the depolarization wave from the SA node through the atria

P wave

1. Intracellular calcium ions (second messenger) ii. Phospholipase C (enzyme) splits a plasma membrane phospholipid, PIP2, into 2 second messengers (DAG: activates protein kinase enzyme and triggers responses within target cell) (IP3: releases Ca2+ from intracellular storage sites, acts as secondary messenger and binds to protein calmodulin which activates enzymes that amplify the cellular response)

PIP2-Calcium Signaling Mechanism

i. Pacemaker potential: hyperpolarization and the end of an action potential closes K+ channels and opens Na+ channels, influx of Na+ alters balance between K= loss and Na+ entry, membrane interior becomes more positive ii. Depolarization: at threshold (-40 mV) Ca2+ channels open, influx of Ca2+ produces rising phase of the action potential and reverses the membrane potential iii. Repolarization: Ca2+ channels inactivate, K+ channels open and Na+ leaves the cells, goes back to membrane potential

Pacemaker cells

soft tadpole-shaped gland composed of endocrine and exocrine glands located behind the stomach

Pancreas

a mixed gland, located close to the stomach and small intestine

Pancreas location

tiny cell clusters that produce pancreatic hormones o Alpha cells: glucagon synthesizing cells o Beta cells: insulin synthesizing cells

Pancreatic islets

small bundles of cardiac muscle that chordae tendineae originate from, project from the myocardial wall

Papillary muscles

act within the same tissue, but affect cell types other than those releasing the paracrine chemicals (somatostatin released by one group of pancreatic cells inhibits the release of insulin by a different group of pancreatic cells)

Paracrines

bundles of muscle tissue that form ridges in the walls of the right atrium

Pectinate muscles

inflammation of the pericardium, causes adhesions between the serous pericardial layers that interfere with heart movement

Pericarditis

double-walled fibroserous sac

Pericardium

if the right side of the heart fails

Peripheral congestion

one hormone cannot exert its full effects without another hormone being present (lack of thyroid hormone delays reproductive development)

Permissiveness

autoimmune disease (elderly) destroys cells of stomach mucosa, which erythrocytes need because stomach mucosa produce intrinsic factor which has to be present for vitamin B12 to be absorbed, without vitamin B12 erythrocytes can grow but can't divide

Pernicious anemia

if afterload is choronically elevated, ESV rises and the myocardium hypertrophies, the stress makes the myocardium weaker

Persistent high blood pressure

pinecone-shapes, hangs from the roof of the third ventricle in the diencephalon

Pineal gland

found in the roof of the third ventricle

Pineal gland location

secretory cells of pineal gland

Pinealocytes

straw-colored sticky fluid, 90% water

Plasma

(55% of whole blood)

Plasma %

130-200mg per 100 ml of plasma (LDL: bad cholesterol, HDL: good cholesterol), Atherosclerosis: disease process in which the body's blood vessels become increasingly occluded by plaques

Plasma cholesterol concentration

cytoplasmic fragments of extraordinarily large cells, megakaryocytes

Platelets

abnormal excess of erythrocytes that increases blood viscosity, causing it to flow sluggishly i. Symptoms: dizziness, high RBC count ii. Causes: living in high altitudes, blood doping

Polycythemia

an increase in the number of RBS, may result from bone marrow cancer or living at high altitudes where less oxygen is available

Polycythemia

substances that increase contractility (glucagon, hormones, Ca2+)

Positive inotropic agents

runs to the heart apex and supplies the posterior ventricular walls, near the apex of the heart, this artery merges with the anterior interventricular artery

Posterior interventricular artery

composed of neural tissue (pituicytes) and nerve fibers, releases neurohormones received by the hypothalamus, hormone-storage area, not true endocrine gland

Posterior pituitary lobe

breast secretory tissue: promotes lactation

Prolactin (PL)

a. Sclerosis (stiff) and thickening of valve flaps b. Decline in cardiac reserve - less able to respond to sudden and prolonged stressors c. Fibrosis of cardiac muscle (scared): more cardiac cells die with age and are replace with scarred tissue reducing stroke volume d. Atherosclerosis - condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol.

Provide examples of age-related changes in heart function

each composed of 3 pocket-like cusps, guards the bases of the two large arteries leaving the ventricular chambers • The valve cusps are forced open and flatten against the walls of the artery as the ventricles discharge their blood into large arteries during systole • However, when the ventricles relax, blood flows backward toward the heart and the cusps fill with blood, closing the semilunar valves and preventing arterial blood from reentering the heart

Pulmonary and aortic valves

blood vessel that carry blood to and from the lungs

Pulmonary circuit

right side, send the carbon dioxide-rich blood entering its chambers to the lungs to unload carbon dioxide and pick up oxygen, and then back to the left side of the heart • Function: provide for gas exchange

Pulmonary circulation

if the lest side of the heart fails

Pulmonary congestion

routes blood to lungs to be oxygenated

Pulmonary trunk

deliver oxygen-rich blood from lungs to the left atrium

Pulmonary veins

long strands of barrel-shaped cells (Purkinje myocytes), ramify within the muscle bundles of the ventricular walls

Purkinje fibers

0.38s, the period from the beginning of ventricular depolarization through ventricular repolarization

Q-T interval

the period from the beginning of ventricular depolarization through repolarization and includes the time of ventricular contraction (the S-T segment) (0.31-0.41 sec) • As the rate increases, the interval becomes shorter, when the heart rate drops, this interval becomes longer

Q-T interval heart rate

0.08s, results from ventricular depolarization and precedes ventricular contraction

QRS complex

repolarization of the atria, obscured by the QRS complex

QRS interval

4-6 million per mm^3 of blood, Since RBCs are absolutely necessary for oxygen transport, a doctor typically investigates an excessive changes in their number immediately

Red blood cell count

composed of a soft network of reticular connective tissue bordering on wide blood capillaries (blood sinusoids)

Red bone marrow

young erythrocyte, still contains a network of clumped ribosomes

Reticulocyte

has auricles, and pectinate muscles i. Blood enters right atrium via three veins 1. Superior vena cava: returns blood from body regions superior to the diaphragm 2. Inferior vena cava: returns blood from body areas below the diaphragm 3. Coronary sinus: collects blood draining from the myocardium

Right Atrium structure and function

guard the bases of the large arteries issuing from ventricles and prevent blackflow into the associated ventricles, fashioned from pocket like cusps, each shaped roughly like a crescent moon

Semilunar valves (SL)

short-lived prostaglandin derivative, messengers that enhance vascular spasm and platelet aggregation

Serotonin and thromboxane A

alteration in one of the amino acids in a beta chain of the globin molecules causes the beta chains to link together under low-oxygen conditions, forming stiff rods so the hemoglobin S becomes spiky and sharp, causes the RBC to become crescent shaped, they rupture very easily and tend to dam up in small blood vessels i. Symptoms: gasping for air, chest pain, bone pain ii. Causes: genetic, occurs in the black people among the malaria belt of Africa

Sickle-cell anemia

located in the right atrium just inferior to the entrance of the superior vena cava

Sinoatrial node (SA node)

long, cylindrical, multinucleated muscle fibers, fibers are independent of one another both structurally and functionally, 2% volume of mitochondria, contracts individual muscles, anaerobic and aerobic respiration

Skeletal muscle

1 of 3 tributaries of the coronary sinus, runs along the heart's inferior margin

Small cardiac veins

cells of anterior lobe that produce growth hormone

Somatropic cells

• Record the voltages generated in the extracellular fluids surrounding the heart by the ion flows occurring simultaneously in many cells between any two of the connections • Einthoven's triangle: the sum of the voltages of Leads I and III equals that in Lead II o Lead I (RA-LA): connects the right arm and left arm and is most sensitive to electrical activity spreading horizontally across the heart o Lead II (RA-LL): record activity along the vertical axis (from the base of the heart to its apex) but from different orientation than Lead III o Lead III (LA-LL): record activity along the vertical axis (from the base of the heart to its apex) but from different orientation than Lead II

Standard Limb Leads

the amount of blood ejected by a ventricle with each contraction (increases with physical conditioning)

Stroke volume

the volume of blood pumped out by each ventricle with each beat, correlated with the force of ventricular contraction (70ml/beat)

Stroke volume

complete cells with nuclei and organelles, less than 1% of total blood volume

Structural characteristics of leukocytes

outer region (stains blue) and inner region (stains purple), contains granules that contain chemicals that act in the clotting process including serotonin, Ca2+, a variety of enzymes, ADP, and platelet-derived growth factor (PDGF)

Structure of platelets

Growth hormone (GH) Thyroid-stimulating hormone (TSH) Adrenocorticotropic hormone (ACTH) Follicle-stimulating hormone (FSH) Luteinizing hormone (LH) Prolactin (PL)

What hormones does the anterior pituitary release?

carries oxygen-rich blood from the left heart through the body tissues and back to the right heart • Function: provides the functional blood supply to all body tissues

Systemic circulation

function in the immune response by acting directly against virus-infected cells and tumor cells

T lymphocytes (T cells)

caused by ventricular repolarization, lasts about 0.16s, lower height than QRS complex because its more spread out

T wave

tissue cells that have receptors for hormonal activity influences, hormone communicates with target cell through water-soluble hormones (amino-acid based hormones, no thyroid, use g proteins) or lipid-soluble hormones (steroid and thyroid hormones) act on receptors inside the cells which directly activates genes, hormone typically produce one or more of these changes: i. Alters plasma membrane permeability or membrane potential, or both, by opening or closing ion channels ii. Stimulates synthesis of enzymes and other proteins within the cell iii. Activates or deactivates enzymes iv. Induces secretory activity v. Stimulates mitosis

Target cells

paired glands suspended in the scrotum

Testes location

drive development of secondary sexual characteristics • Release stimulated by another hormone • Hyposecretion: sexual immaturity

Testosterone

initiates the maturations of the males reproductive organs and the appearance of secondary sex characteristics and sex drive, normal sperm production, maintains the reproductive organs in their mature functional state in adult males

Testosterone (Testes)

one of the globin chains is absent or faulty, and the erythrocytes are thin, delicate, and deficient in hemoglobin (typically occur in Mediterranean ancestry)

Thalassemias

1. cAMP (second messenger) ii. Hormone binds receptor (hormone acts as first messenger) iii. Receptor activates G protein (G protein activated by GDP: off, GTP: on) iv. G protein activates adenylate cyclase (enzyme) v. Adenylate cyclase converts ATP to cAMP vi. Cyclic AMP activates protein kinases (enzymes that add a phosphate group to proteins, can activate or inhibit certain proteins)

The Cyclic AMP signaling Mechanism

Superior vena cava, inferior vena cava, coronary sinus → Right atrium → tricuspid valve to Right ventricle → pulmonary semilunar valve to Pulmonary trunk → Lungs (oxygen-poor blood is carried into two pulmonary arteries to the lungs: pulmonary circuit to be oxygenated) → Heart (oxygen-rich blood returns to the heart via the four pulmonary veins) → Left atrium → through the mitral valve to the Left Ventricle → through the Aortic semilunar valve to the Aorta → to body (oxygen-rich blood is delivered to the body tissues: systemic circuit)

Trace the pathway of blood through the heart

heart rate over 100 beats/min (normal is 70 beats/min)

Trachycardia

protein that transports iron through blood

Transferrin

Preload Contractility Afterload

Three main factors affect Stroke volume

causes spontaneous bleeding from small blood vessels all over the body, arises from conditions that suppress or destroy red bone marrow

Thrombocytopenia (bleeding disorder)

result from condition that cause undesirable clot formation

Thromboembolic disorders

a clot that develops and persists in an unbroken blood vessel, can block circulation to the cells beyond the blockage and lead to the death of those tissues, heart attack

Thrombus (Thromboembolic disorders)

hormone that regulated the formation of platelets

Thromobopoietin

found in the upper thorax overlying the heart, large during youth

Thymus location

located in the anterior neck, on the trachea just inferior to the larynx, largest pure endocrine gland in the body

Thyroid gland

located in the throat, bilobed gland connected by an isthmus

Thyroid gland location

increasing basal metabolic rate and body heat production by turning on transcription of genes concerned with glucose oxidation (calorigenic effect: heat producing), regulating tissue growth an development (critical for normal skeletal and nervous system development and maturation and for reproductive capabilities), maintaining blood pressure by increasing the number of adrenergic receptors in blood vessels

Thyroid hormone

thyroid gland: stimulates thyroid gland to release thyroid hormones

Thyroid-stimulating hormone (TSH)

o Right and Left coronary arteries: issue from the base of the aorta just above the aortic semilunar valve and encircle the heart in the coronary sulcus (Atrioventricular groove) at the junction of the atria and ventricles o They then ramify over the heart's surface, the right coronary artery supplying the posterior surface of the ventricles and the lateral aspect of the right side of the heart, largely through its Posterior interventricular and marginal artery branches o The left coronary artery supplies the anterior ventricular walls and the laterodorsal part of the left side of the heart via its two major branches, the anterior interventricular artery and the circumflex artery o The coronary arteries and their branches are compressed during systole and fill when the heart is relaxed o The myocardium is largely drained by the great, middle, and small cardiac veins, which empty into the coronary sinus. o The coronary sinus empties into the right atrium o Several anterior cardiac veins empty directly into the right atrium

To name and follow the functional blood supply of the heart

pitted and ridged appearance of the inner ventricular muscle

Trabeculae carneae

Oxygen poor blood from body goes through the superior and inferior vena cavae → right atrium →right ventricle → pulmonary trunk → pulmonary arteries → to the lungs for gas exchange to receive oxygen and dump carbon dioxide Oxygen rich blood from lungs goes through the pulmonary veins → left atrium → left ventricle → out the aorta → to the body tissues

Trace the pathway of blood through the heart

Tricuspid valve Mitral/ Bicuspid valve

What are the 2 atrioventricular valves (AV) valves

Mineralcorticoids Glucocorticoids Gonadocorticoids

What are the hormones produced by the adrenal gland?

i. When mismatched blood is infused a reaction occurs in which the recipient's plasma antibodies attack the donor's red blood cells ii. The transfused blood cells cannot transport oxygen iii. The clumped red blood cells in small vessels hinder blood flow to tissues beyond those points iv. Hemoglobin escapes into the bloodstream and cause the kidneys to shut down v. Can result in fever, chills, low blood pressure, rapid heartbeat, nausea, vomiting, and general toxicity

Transfusion reactions

right AV valve, has 3 flexible cusps (flaps of endocardium reinforced by connective tissue cores)

Tricuspid valve

right atrioventricular valve, 3 cusps

Tricuspid valve (AV valve)

regulate the secretory action of other endocrine glands (all anterior pituitary hormones except growth) (cyclic AMP system)

Tropic hormones

persistently low levels of a hormone can cause its targets to form additional receptors for that hormone

Up-regulation

the amount of blood returning to the heart and distending its ventricles

Venous return

thin layer that touches the heart

Visceral Pericardium/Epicardium

i. Evidence of coronary artery disease, locate damaged heart tissue, and detect other cardiovascular disorders j. An ECG tracing can provide a baseline examination of the tissues of the heart and can show whether a heart attack, or myocardial infarction, has occurred. Following a heart attack, an ECG can be used to examine the electrical activity in various areas and tissues of the heart and to help find damaged areas

What abnormalities that can be tested with an ECG

Mineralocorticoids Glucocorticoids Gonadocorticoids

What are corticoids broken down into?

Formed elements: living cells that are suspended in plasma

What are formed elements?

seal small tears in blood vessels, instrumental in blood clotting, discoid cytoplasmic fragments (megakaryocytes) containing granules, stain deep purple, diameter 2-4 um, D: 4-5 days, LS: 5-10 days, 150,000-400,000 per mm^3 of blood

What are platelets

i. Delivering oxygen from the lungs and nutrients from the digestive tract to all body cells ii. Transporting metabolic waste products from cells to elimination sites (to the lungs to eliminate carbon dioxide, and to the kidneys to dispose of nitrogenous wastes in urine) iii. Transporting hormones from the endocrine organs to their target organs

What are the transport functions of blood?

Aortic valve Pulmonary valve

What are the two semilunar valves

chiefly androgens, but some estrogens are formed • Estrogen • Testosterone

What do gonadocorticoids do?

regulate water and electrolyte balance in the extracellular fluids o Aldosterone: maintenance of salt water balance in the extracellular fluid • Release stimulated by humoral factors (the concentrations of specific nonhormonal substances in the blood or extracellular fluid) o Produced by zona glomerulosa cells

What do mineralocorticoids do?

Estrogen Progesterone

What do the ovaries produce?

enable the body to resist long-term stressors, by increasing blood glucose levels o Cortisone: released in response to stressors o Hydrocortisone o Corticosterone o Produced by zona fasciculata cells in the adrenal gland

What doe glucocorticoids do?

regulate the function of another endocrine gland (tropic hormone) • Produced by basophil cells of the anterior pituitary

What does ACTH do?

maintenance of salt and water balance in the extracellular fluid, reduces urine output • Release is stimulated by the nervous system • Hyposecretion: excessive diuresis without high blood glucose levels

What does ADH do?

regulate blood calcium levels, decreases • Produced by parifollicular cells of the thyroid

What does Calcitonin do?

drive development of secondary sexual characteristics, directly responsible for the regulation of the menstrual cycle • Released due to the stimulation of another hormone • Hyposecretion: sexual immaturity

What does Estrogen do?

regulate the function of another endocrine gland (tropic hormone), regulate the ovarian cycle • Release stimulated by another hormone • Produced by basophil cells of the anterior pituitary

What does FSH do?

metabolic hormone that plays an important role in determining body size • Hyposecretion: abnormally small stature, normal proportions • Hypersecretion: large hands and feet in the adult, large facial bones • Produced by acidophil cells of the anterior pituitary

What does GH do?

regulate blood glucose levels, increases • Produced by alpha cells of the pancreatic islets (islets of Langerhans)

What does Glucagon do?

regulate the function of another endocrine gland (tropic hormone), regulate the ovarian cycle • Produced by basophil cells of the anterior pituitary

What does LH do?

questionable function, may stimulate the melanocytes of the skin

What does MSH (melanocyte stimulating hormone) do?

regulate blood calcium levels • Release stimulated by humoral factors (the concentration of specific nonhormonal substances in the blood or extracellular fluid) • Hyposecretion: Tetany (prolonged muscle spasms that can lead to respiratory paralysis and death) • Hypersecretion: demineralization of bones, spontaneous fractures • Produced by chief cells

What does PTH do?

broken into T4/T3: control the rate of body metabolism and cellular oxidation • Release stimulated by another hormone • Produced by follicular epithelial cells of the thyroid • T4 (thyroxine) • Hyposecretion: low BMR, mental and physical sluggishness • Hypersecretion: nervousness, irregular pulse rate, sweating

What does TH do and what is it broken down into?

regulate the function of another endocrine gland (tropic hormone) • Release stimulated by another hormone • Produced by basophil cells of the anterior pituitary

What does TSH do?

regulate blood glucose levels, decreases • Release stimulated by the nervous system • Produced by beta cells of the pancreatic islets (islets of Langerhans) • Hyposecretion: diabetes mellitus: loss of glucose in the urine • Hypersecretion: polydipsia, polyurea, polyphagia

What does insulin do?

helps regulate the sleep-wake cycle, and prevent precocious sexual maturation

What does melatonin do?

directly involved in milk production and ejection • Hypothalamus makes these hormones but the posterior pituitary secretes them

What does oxytocin do?

directly responsible for the regulation of the menstrual cycle

What does progesterone do?

directly involved in milk production and ejection • Produced by acidophil cells of the anterior pituitary

What does prolactin do?

Epinephrine Norepinephrine

What does the Adrenal Medulla produce?

o Influences metabolic activity by means of hormones (chemical messengers secreted by cells into the extracellular fluid) • Reproduction • Growth and development • Maintenance of electrolyte, water, and nutrient balance of the blood • Regulation of cellular metabolism and energy balance • Mobilization of body defenses

What does the Endocrine system influence?

Corticoids

What does the adrenal cortex produce?

ACTH FSH LH TSH PRL MSH GH

What does the anterior pituitary produce?

ADH Oxytocin

What does the hypothalamus produce?

Glucagon Insulin

What does the pancreas produce?

parathyroid hormone (PTH)

What does the parathyroid gland secrete?

Melatonin

What does the pineal gland produce?

Thymosin Thymopoietin

What does the thymus produce?

programming of T lymphocytes

What does thymosin do?

25% WBC population, mount immune response by direct cell attack or via antibodies, nucleus spherical or indented, pale blue cytoplasm, diameter 5-17 um, D: days to weeks, LS: hours to years, 1500-3000 per mm^3 of blood • B lymphocytes: oversees the production of antibodies that are released to the blood • T lymphocytes: plays a regulatory role and destroys grafts, tumors, and virus-infected cells

What is a Lymphocyte

less than 1% WBC population, release histamine and other mediators of inflammation, contain heparin (an anticoagulant), nucleus lobed, large blue-purple cytoplasmic granules, diameter 10-14 um, D: 1-7 days, LS: a few hours to a few days, 20-50 per mm^3 of blood

What is a basophil

2-4% WBC population, kill parasitic worms, destroy antigen antibody complexes, inactivate some inflammatory chemical of allergy, nucleus bi-lobed, red cytoplasmic granules, diameter 10-14 um, D: 14 days, LS: 8-12 days, 100-400 per mm^3 of blood

What is a eosinophil

3-8% WBC population, phagocytosis, develop into macrophages in tissues, nucleus U or kidney-shaped, gray-blue cytoplasm, diameter 14-24 um, D: 2-3 days, LS: months, 100-700 per mm^3 of blood

What is a monocyte

40-70% WBC population, phagocytize bacteria, nucleus multi-lobed, inconspicuous cytoplasmic granules, diameter 10-12 um, D: 14 days, LS: 14 hours to a few days, 3000-7000 per mm^3 of blood

What is a neutrophil

a nonliving fluid matrix • 90% water: solvent for carrying other substances; absorbs heat • Electrolytes (Sodium, Potassium, Calcium, Magnesium, Chloride, Bicarbonate): Osmotic balance, pH buffering, regulation of membrane permeability • Plasma proteins • Albumin: Osmotic balance, pH buffering • Fibrinogen: Clotting of blood • Globulins: Defense (antibodies) and lipid transport

What is plasma made up of?

a. Composition of plasma: i. 90% water ii. 10% nutrients, gases, hormones, wastes and products of cell activity, proteins, and inorganic ions (electrolytes, mostly Na+ and Cl-) b. Function of plasma: i. Maintains osmotic pressure in blood ii. Blood buffer

What is the composition and function of plasma

Important to our biological clock, bright light suppresses melatonin whereas darkness allows us to produce melatonin to become sleepy, changing melatonin levels may influence rhythmic variation is physiological processes such as body temperature, sleep, and appetite

What is the importance of melatonin?

right marginal artery posterior interventricular artery

What is the right coronary artery broken into...

Oxytocin ADH

What two hormones does the posterior pituitary release?

stomach, intestine, pancreas

Where are enteroendocrine cells located?

4,800-10,800 per mm^3 of blood, Since white blood cells are an important part of the body's defense system, it is essential to note abnormalities in them

White blood cell count

because it must pump blood through the much longer systemic circulation that has higher resistance than the pulmonary circulation

Why are left ventricle muscles thicker?