what does the heart do
a pump that provides the force needed to move blood
the routes along which blood moves from one area of the body to another
provide the surfaces across which exchange between plasma and Interstitial fluid occurs
heart is made of
cardiac muscle tissue, connective tissue, and epithelial tissue and it has nerves and vessels (blood and lymphatic)
muscle tissue has
striated cells and many of the cells branch
the heart is lined by a membrane composed of …
endothelium and connective tissue
the outside layer of the heart is the …
sac like structure that surrounds the heart
-composed of dense connective tissue
- two parts
- parietal and visceral
-lines the inside of the fibrous pericardium
covers the heart itself (on the viscera)
fills the pericardial cavity
- reduces friction
blood travels away from the chambers in ___.
blood traveled toward the chambers via ___
the arteries of the pulmonary circuit take blood to the
blood is pumped by the left ventricle into the _____ circuit.
the arteries of the systemic circuit take blood to _____
all parts of the body
as blood flows through pulmonary capillaries it picks up ____ and loses ____.
oxygen ; carbon dioxide
as blood flows through the systemic capillaries, substances are exchanged between it and the IF. what are the substances?
oxygen , carbon dioxide, nutrients, cellular waste products
the largest veins of the systemic circuit empty blood into the ______.
the pericardial cavity is located between the
visceral pericardium and the parietal pericardium
fetal blood flows to and from the placenta via ___.
the placenta has both _____ and _____ blood vessels
fetal and maternal blood vessels
an opening in the interatrial septum
a vessel connecting the pulmonary trunk and aortic arch
what do the foramen ovale and ductus arteriousus do?
the allow most blood to bypass the pulmonary circulation
allows some blood to bypass the hepatic (liver) vessels
specialized cardiac muscle cells in the atria secrete a hormone called ____. what is ists function
atrial natriuretic peptide
aveolar and capillary walls are the surfaces across which _____ occurs.
the walls of the airways in the respiratory system have ____ or ___ to prevent them fro collapsing.
bone or cartilage
many of the airways are lined by _______.
explain the significance of ciliated epithelium in the airways
small particles that are inhaled stick to the mucus secreted by this epithelium and ciliary action moves the mucus and entrapped particles out of the airwaysw
alveolar walls are composed of _______.
simple squamous epithelium
what is the significance of alveolar walls being composed of simple squamous epithelium?
the thin membrane makes it easy for gases to diffuse
covers the lung directly
lines the wall of the thoracic cavity
what type of fluid fills the pleural cavity?
what does pleural fluid do
acts a lubricant that reduces friction during lung movements
-acts as an adhesive that helps in lung expansion and prevents collapse of the lungs
the only portion of the digestive tract found in the thoracic cavity is the ______.
the esophagus extends from the _____ to the ____ where is passes through the foramen (hiatus) into the abdominal cavity
laryngopharynx to the diaphragm
the layers of the esophageal wall are the same as we studied before except which exception
- the muscularis externa
- in the first two thirds of the esophagus it is composed of skeletal muscle tissue, but in the last one third, it is composed of smooth muscle tissue.
located over the heart in fetus
- eventually replaced by connective tissue
- endocrine organ that secretes hormones
- organ of the lymphatic system involved in immunity
innervates the diaphragm
innervates structures of the thorax
a series of ganglia called the ___________ run along either side of the vertebral column.
sympathetic chain ganglia
function of the heart
-located in the mediastinum between ribs 2-5
-formed mostly by the L atrium
-located in the left 5th intercostal space (slightly below left nipple)
receives blood from the systemic veins
superior vena cava
drains the head, neck, thorax, and upper limbs
-feeds the right atrium
inferior vena cava
- drains the lower limbs and the abdominal and pelvic regions
- feeds the right atrium
pumps blood through the pulmonary circuit
takes blood to the lungs
-exits right ventricle
- take blood to the lungs
- drain blood from the lungs
receives blood from the pulmonary veins
pumps blood through the systemic system
its branches supply the entire body
supplies most of the body
chord extending from the pulmonary trunk to the aortic arch
-remnant of the ductus arteriosus
thin region in the interatrial septum
-remnant of the foramen ovale
prevent the backflow of blood into the atria
anchors cusps to the papillary muscles
-prevent eversion of the cusps
anchor chordae tendineae to the ventricular walls’ prevent eversion of the cusps
prevent backflow of blood into the ventricles
right coronary artery
- runs to the back of the heart
- supllies the heart
posterior interventricular artery
- branches from the right coronary arter
- runs to the apex
- supplies the posterior ventricular walls
left coronary artery
- branches from the left side of the ascending aorta
- supplies the heart
anterior interventricular artery
- branch of the left coronary artery
- runs to the apex
- supplies the interventricular septum and the anterior ventricular walls
formed by the merging of cardiac veins
-drains the heart
true or false: papillary muscles cause atrioventricular valves to open