Ch. 13 Heart Anatomy

mediastinum

medical space between the lungs

pericardium

protects the heart

base

superior region of the heart

apex

pointed inferior region of the heart

cardiac notch

the depression in the left lung to make space for the heart

hypertrophy

the increase of size of individual cells without increasing numbers. ex:athletes

pulmonary circuit

transports blood to and from lungs where it picks up O2 and delivers CO2 for exhalation; begins at RV and ends at LA

systemic circuit

transports oxygenated blood to all organ systems and returns relatively deoxygenated blood and CO2 to heart to be sent back to pulmonary circulation; begins at LV and ends at RA

fibrous pericardium

made of tough CT for protection

serous pericardium

delicate and made of 2 layers, parietal pericardium and visceral pericardium

auricles

superficial flaps on the atria near surface of heart; thin walled, fill with blood and then empty into atria

sulcus (sulci)

fat filled grooves along superior surface of heart

coronary arteries

delivers O2 rich blood to myocardium to nourish cardiac muscle cells

coronary veins

return deoxygenated blood back to RA

epicardium

outermost thin layer fused to the heart

myocardium

middle and thickest layer of the heart, made mostly of cardiac muscle cell

right atrium

receiving chamber for blood returning to heart via systemic circulation

pectinate muscles

prominent ridges of muscle

tricuspid valve

opening between RA and RV

right ventricle

receives blood from RA through tricuspid valve

chordae tendineae

strong strands of CT that Each flap of the valve attaches to

trabeculae carneae

ridges that line walls of RV; prevents suction

pulmonary semilunar valve

at base of pulmonary trunk

bicuspid valve (mitral valve)

opening between LA and LV

autorhythmicity

ability of specialized conductive cardiac muscle cells to indicate an electrical charge that spreads rapidly cell to cell

cardiac conduction system

the electrical signal travels along a specific pathway involving many conducting structures

sinoatrial node (SA)

specialized clumps of charge generating cells located in RA; highest inherit rate of depolarization; aka pacemaker

atrioventricular node

clump of cells in RA in between atria and ventricles; delays transmission of the electrical signal

atrioventricular bundle

proceeds through interventricular septum before diving into 2 branches; both branches descend and reach the apex where they connect with Purkinje fibers

Purkinje fibers

spread the impulse into the myocardium of the ventricles

varicose veins

twisted veins that usually appear on the legs and feet; occur when the valves in the veins fail to function properly, causing blood to pool instead of flowing efficiently back to the heart.

Neutrophils

The most abundant white blood cells. They are the first responders to infections, engulfing and destroying bacteria and fungi through phagocytosis.

Lymphocytes

play a key role in adaptive immunity, producing antibodies and attacking infected or cancerous cells

monocytes

The largest type of leukocyte. They transform into macrophages and dendritic cells, which help remove dead cells and pathogens while also activating other immune responses.

eosinophils

involved in allergic reactions and parasitic infections, releasing toxic granules to kill invaders.

basophils

The least common but crucial for inflammatory responses. They release histamine, which helps regulate allergic reactions and inflammation.