Anatomy Final Flashcards
What are the functions of the cardiovascular system?
Responsible for transporting blood throughout the body. Blood transports oxygen, nutrients, wastes, hormones, etc.
System of blood vessels and a heart. Heart is responsible for moving the blood
Network of blood vessels approx. 100,000 km long
What does the right side of the heart do?
Receives oxygen-poor blood from tissues
Pumps blood to lungs to get rid of CO2, pick up O2, via pulmonary circuit.
What does the left side of the heart do?
Left side receives oxygenated blood from lungs.
Pumps blood to body tissues via systemic circuit.
What are the receiving chambers of the heart?
Right atrium: Receives blood returning from systemic circuit
Left atrium: Receives blood returning from pulmonary circuit
What are the pumping chambers of the heart?
Right ventricle: pumps blood through pulmonary circuit
Left ventricle: pumps blood through systemic circuit
What separates the right ventrical from the left ventricle interiorly?
The interventricular septum
What is the heart’s position in the thoracic cavity?
left of midline, deep to sternum, mediastinum
What forms the base of the heart?
Left atrium, superior border (great vessels and superior vena cava)
What forms the apex of the heart?
Tip of left ventrical and the inferior border = right ventrical
What is the purpose of the pericardium?
Encloses the heart. Restricts movement (allows slight amount).
What are the two parts of the pericardium?
The fibrous pericardium and the serous pericardium.
Describe the serous pericardium.
One part of the pericardium. Composed on the parietal and visceral epicardium layers: pericardial cavity in between.
Where are auricles found?
In the atria. They are muscular extensions of atria. They are small, wrinkled, protruding appendages called auricles (or′ĭ-klz; auricle = little ear), which increase the atrial volume somewhat
Where is posterior sulcus located?
between the right and left ventricles
What are the functions of heart valves?
- Ensure unidirectional blood flow through heart.
- Open and close in response to pressure changes.
Why are there no valves between major veins and atria?
- Inertia of incoming blood prevents backflow.
- Heart contractions compress venous openings.
What are the two major types of heart valves?
Atrioventricular valves and semilunar valves.
Where are atrioventricular valves located?
Between atria and ventricles.
Where are semilunar valves located?
between ventricles and major arteries.
Name 2 atrioventricular valves and outline where they are located.
The tricuspid valve is the right atrioventricular valve and is between the right atria and ventricle. The mitral valve is the left AV valve, and is bicuspid. It is located between the left atria and ventricle.
What is the purpose of the atrioventricular valve? Explain how the AV valves open.
Prevent backflow into atria. When blood returning to the heart fills the atria, it presses against the AV valves. This increased pressure forces AV valves open. As the ventricles fill, the AV flaps hang limply into the ventricles. The atria contract, forcing additional blood into ventricles.
Name two structures associated with the AV valves.
Chordae tendineae (heart strings) and papillary muscles.
Describe the general systemic and pulmonary circulation.
The right side of the heart receives oxygen-poor blood from body tissues and then pumps this blood to the lungs to pick up oxygen and dispel carbon dioxide. The blood vessels that carry blood to and from the lungs form the pulmonary circuit (pulmo = lung).
The left side of the heart receives the oxygenated blood returning from the lungs and pumps this blood throughout the body to supply oxygen and nutrients to body tissues. The blood vessels that carry blood to and from all body tissues form the systemic circuit.
What is the heart wall comprised of (from superficial to deep)?
Epicardium, myocardium, and endocardium
How does blood enter the right atrium?
The superior vena cava returns blood from body regions superior to the diaphragm.
The inferior vena cava returns blood from body areas below the diaphragm.
The coronary sinus collects blood draining from the myocardium.
Define pulmonary veins.
Vessels that deliver freshly oxygenated blood from the respiratory zones of the lung to the heart.
Do the atria or the ventricles make up the most of the volume of the heart?
Ventricles
Why are the walls of the ventricles more massive than atria walls?
The ventricles are the discharging chambers, the actual pumps of the heart. Their walls are much more massive than the atrial walls, reflecting the difference in function between the atria and ventricles. When the ventricles contract, they propel blood out of the heart into the circulation.
Where does the right ventricle pump blood into?
Into the pulmonary trunk, which routes the blood to the lungs where gas exchange occurs
Where does the left ventricle eject blood into?
The aorta, the largest artery in the body.
The heart is in the mediastinum. Just what is the mediastinum?
The mediastinum is the medial cavity of the thorax within which the heart, great vessels, thymus, and parts of the trachea, bronchi, and esophagus are found.
From inside to outside, list the layers of the heart wall and the coverings of the heart.
The layers of the heart wall are the endocardium, the myocardium, and the epicardium. The epicardium is also called the visceral layer of the serous pericardium. This is surrounded by the parietal layer of the serous pericardium and the fibrous pericardium.
What is the purpose of the serous fluid inside the pericardial cavity?
The serous fluid decreases friction caused by movement of the layers against one another.
What are two heart valve disorders? What is their result and how can they be fixed?
Incompetent valve is a valve that does not close tightly, forces the heart to repump the same blood over and over because the valve does not close properly and blood backflows.
In valvular stenosis the valves become hardened. the valve flaps become stiff and constrict the opening. The constricted opening compels the heart to contract more forcibly than normal.
Both types of valve problems increase the heart’s workload and may weaken the heart severely over time. The mitral and aortic valves are most often affected.
Can be replaced by mechanical, animal or cadaver valves.
What is the function of the papillary muscles and chordae tendineae?
The papillary muscles and chordae tendineae keep the AV valve flaps from everting into the atria as the ventricles contract.
Name the valve that has just two cusps.
The mitral (left atrioventricular) valve has two cusps.
Describe the workload difference between the right and left vetricle.
Equal volumes of blood are pumped to the pulmonary and systemic circuits at any moment, but the two ventricles have very unequal workloads. The pulmonary circuit, served by the right ventricle, is a short, low-pressure circulation. In contrast, the systemic circuit, associated with the left ventricle, takes a long pathway through the entire body and encounters about five times as much friction, or resistance to blood flow.
Describe the structural differences between the left and right ventricles.
The walls of the left ventricle are three times thicker than those of the right ventricle, and its cavity is nearly circular.
The right ventricular cavity is flattened into a crescent shape that partially encloses the left ventricle, much the way a hand might loosely grasp a clenched fist.
Describe the pathway of blood through through the right side of the heart.
- Superior vena cava, inferior vena cava, coronary sinus
- right atrium
- tricuspid valve
- right ventricle
- pulmonary semilunar valve
- pulmonary trunk
- pulmonary arteries
- lungs
Describe a cardiac cycle.
Start of one heartbeat to initiation of the next. Contraction = systole and Relaxation = diastole.
Describe the pathway through the left side of the heart.
- Four pulmonary veins
- Left atrium
- Mitral valve
- Left ventricle
- Aortic semilunar valve
- Aorta
= systemic circulation
True or false? Equal volumes of blood are pumped to pulmonary and systemic circuits?
True
Which circuit involves short, low-pressure circulation?
Pulmonary circuit
Which circuit involves long, high friction circulation?
Systemic circuit
How does the heart get nourishment?
Through coronary circulation
What is coronary circulation?
The functional blood supply of the heart and the shortest circulation in the body.
What is the function of the coronary sinus?
deoxygenated blood into the right atrium.
Describe the location and function of the coronary sulcus.
The left and right coronary arteries both arise from the base of the aorta and encircle the heart in the coronary sulcus. They provide the arterial supply of the coronary circulation.
What is a myocardial infarction and what is the result?
results from the blockage in one of these vessels. results in death of tissue (heart muscle) and heart attack.
What are the two parts of the serous pericardium?
parietal and visceral layers
What are the names and locations of the four heart valves?
Atrioventricular valves: Tricuspid valve (right AV valve): between right atria and ventricle Mitral valve (left AV valve): between left atria and ventricle
Semilunar valves:
pulmonary semilunar valve: between right ventricle and pulmonary trunk
aortic semilunar valve: between left ventricle and aorta
Name the three classes of blood vessels:
arteries, veins and capillaries
Define ‘great vessels’.
The arteries and veins entering and leaving the heart.
What are the coverings of blood vessels called?
The walls of all blood vessels, except the very smallest, have three distinct layers, or tunics (“coverings”), that surround a central blood-containing space, the vessel lumen.
Describe the innermost tunic.
The innermost tunic is the tunica intima (in′tĭ-mah). The name is easy to remember once you know that this tunic is in intimate contact with the blood in the lumen. The tunica intima contains the endothelium, the simple squamous epithelium that lines the lumen of all vessels.
Describe the middle tunic.
The middle tunic, the tunica media (me′de-ah), is mostly circularly arranged smooth muscle cells and sheets of elastin.
Describe the outermost tunic of the blood vessel wall.
The outermost layer of a blood vessel wall, the tunica externa (also called the tunica adventitia; ad″ven-tish′e-ah; “coming from outside”), is composed largely of loosely woven collagen fibers that protect and reinforce the vessel, and anchor it to surrounding structures. The tunica externa is infiltrated with nerve fibers, lymphatic vessels, and, in larger veins, a network of elastic fibers. In larger vessels, the tunica externa contains a system of tiny blood vessels, the vasa vasorum (va′sah va-sor′um)—literally, “vessels of the vessels”—that nourish the more external tissues of the blood vessel wall.
Name three types of arteries.
elastic, muscular, arterioles
Which type if artery is the largest in diameter?
elastic
What does an artery do?
takes blood away from the heart
What does a vein do?
in carries blood to the heart
Which type of artery has the smallest diameter?
arterioles
Describe elastic arteries.
Largest in diameter, near the heart (the aorta and its major branches), has elastic fibers due to high pressure so needs some give; branches into muscular arteries. Elastic arteries are pressure reservoirs, expanding and recoiling as the heart ejects blood.
Describe muscular arteries.
Medium-sized; elastic fibers in two concentric rings between the three tunics: internal elastic lamina and external elastic lamina; muscular arteries have thicker tunica media.
Describe arterioles.
smallest artery type; less than six cell layers of smooth muscle in tunice media; sympathetic innervation to tunica media, which causes constriction; parasympathetic innervation causes vasodilation and lowers blood pressure.
What are the smallest blood vessels?
capillaries
Name the type of artery that matches each description: major role in dampening the pulsatile pressure of heart contractions; vasodilation or constriction determines blood flow to individual capillary beds; have the thickest tunica media relative to their lumen size.
Elastic arteries play a major role in dampening the pulsatile pressure of heart contractions. Dilation or constriction of arterioles determines blood flow to individual capillary beds. Muscular arteries have the thickest tunica media relative to their lumen size.
Which tunica does capillaries have?
Tunica intima (single layer) - need for diffusion
What leaves and what enters the capillary blood through metabolic exchange?
Oxygen, nutrients and hormones leave the capillary blood and CO2, nitrogenous wastes and other wastes enter the capillary blood.
What are the arteries and the veins entering and leaving the heart known as?
great vessels
What provides larger blood vessels with their own supply?
Vasa vasorum (tunica external)
Which branch of the autonomic nervous system innervates blood vessels? Which layer of the blood vessel wall do these nerves innervate? What are the effectors (cells that carry out the response)?
The sympathetic nervous system innervates blood vessels. The sympathetic nerves innervate the tunica media. The effector cells in the tunica media are smooth muscle cells.
When vascular smooth muscle contracts, what happens to the diameter of the blood vessel? What is this called?
When vascular smooth muscle contracts, the diameter of the blood vessel becomes smaller. This is called vasoconstriction.
Which type of artery determines blood flow to capillary beds?
Minute-to-minute blood flow into the capillary beds is determined by arteriolar diameter, which varies in response to changing neural, hormonal, and local chemical influences.
Define continuous capillaries.
Most common and least permeable. They form a complete lining. (e.g. skin, muscles and lungs)
Define fenestrated capillaries.
They contain pores that increase permeability and allow for fluid exchange (e.g. kidneys)
Define sinusoid capillaries.
The most permeable and occur in limited locations. Allows for cell and large molecule transport (e.g. spleen primarily (rbc breakdown and immune cells need to get out), bone marrow)
In the systemic circuit, which contains more blood—arteries or veins—or is it the same?
In the systemic circuit, veins contain more blood than arteries.
What is the primary function of the respiratory system?
inhalation and exhalation: exchange of O2 and CO2
What other functions does the respiratory system have besides its primary?
gas conditioning, sound production, olfaction, and defense
What sections is the upper respiratory tract divided into?
Nose and nasal cavities, paranasal sinuses and pharynx
What does the nose and nasal cavity do?
warms and humidifies the air
What do the paranasal sinuses do?
warms and humidifies the air, lightens skull and provides a resonance chamber
What two regions share the pharynx?
respiratory and digestive
What three regions is the pharynx divided into?
nasopharynx (nasal), oropharynx (oral) and laryngopharynx (‘larynx’) (listed from superior to inferior)
Where is the nasopharynx located?
continuous with nasal cavity, superior to the soft palate
Where are the pharyngotympanic (Eustacian) tubes found and what is their purpose?
In the lateral walls of the nasopharynx. Their purpose is drainage and equalizing pressure.
What is located in the posterior region of the nasopharynx and what does it contain?
The pharyngeal tonsil. It contains immune cells.
What is a tonsil?
A mass of lymphoid tissue.
What is the location of the oropharynx?
It is one region of the pharynx and is located between the soft palate and the hyoid bone.
What is located in the lateral wall of the oropharynx?
The palatine tonsils.
What is located in the oropharynx at the base of the tongue?
The lingual tonsils.
What lines the laryngopharynx?
tough epithelial
Where is the laryngopharynx located?
from the hyoid to the top of the esophagus.
Is the laryngopharynx located posteriorly or anteriorly to the larynx?
posteriorly
What is the conducting portion of the lower respiratory tract?
larynx, trachea, bronchi and bronchioles
What is the respiratory portion of the lower respiratory tract?
respiratory bronchioles, alveolar ducts, alveoli
What are the functions of the larynx?
air, blocks ingested material from respiratory tract, sound, increases pressure in the abdominal cavity and sneeze and cough reflex
What else is the larynx known as?
voice box
What is the laryngeal prominence and is the same in both genders?
It is the Adam’s apple. More prominent in men due to testosterone during development.
List the order of the anatomy of the larynx.
Epiglottis, Thyroid cartilage, laryngeal prominence, cricoid cartilage
What happens when we swallow food?
The epiglottis acts as a flap and saves you from choking on food.
What else is the trachea known as and what does it branch into?
It is known as the windpipe and branches into primary bronchi
How many C-shaped cartilages are found in the trachea and how are they connected?
16 - 20 and they are connected by anular ligaments
Why is the trachea lined with mucous-producing cells?
Prevents pathogens from entering the lungs.
Why is the bronchial tree highly branched?
To increase surface area.
Where does the bronchial tree start and end?
The bronchial tree originates in the main bronchi and terminates in the terminal bronchioles.
What is the secondary bronchi called?
lobar bronchi
What is the tertiary bronchi called?
segmental bronchi
List some characteristics of bronchioles.
- lack cartilage
- simple squamous/columnar epithelial
- < 1 mm in diameter
- walls are thick layers of smooth muscle to dilate bronchioles to bring more air in
- they branch into terminal bronchioles
Describe the structure of the trachea and its role in the body.
It branches into primary bronchi and has 16-20 C-shaped cartilages connected by anular ligaments. It acts as an air passageway, cleans, warms and moistens the incoming air.
What is the function of the bronchiole tree?
Air passageways connecting trachea with alveoli; cleans and warms the incoming air as well as moistens it
Describe the structure and function of alveoli.
Microscopic chambers at the termini of the bronchiole tree. Walls of simple squamous epithelium overlie thin basement membrane. External surfaces are intimately associated with pulmonary capillaries. They are the main site of gas exchange.
What is the path after the terminal bronchioles?
respiratory bronchioles, alveolar ducts then alveoli
Air moving from the nose to the larynx passes by a number of structures. List (in order) as many of these structures as you can.
The structures that air passes by are the nasal cavity, nasopharynx, oropharynx, and laryngopharynx.
Define the respiratory zone.
The respiratory zone, the actual site of gas exchange, is composed of the respiratory bronchioles, alveolar ducts, and alveoli, all microscopic structures.
Define the conducting zone.
The conducting zone consists of all of the respiratory passageways from the nose to the respiratory bronchioles. These provide fairly rigid conduits for air to reach the gas exchange sites. The conducting zone organs also cleanse, humidify, and warm incoming air.
What forms the respiratory membrane?
capillary and alveolar Type 1) walls and their fused basement membranes
What is the function of the respiratory membrane?
Gas exchanges occur readily by simple diffusion across the respiratory membrane—O2 passes from the alveolus into the blood, and CO2 leaves the blood to enter the gas-filled alveolus.
What are Type 1 alveolar cells?
are squamous epithelial cells that form the major part of the alveolar walls.
What are Type 2 alveolar cells?
cuboidal epithelial cells that are scattered among the type I cells. They secrete a fluid containing a detergent-like substance called surfactant that coats the gas-exposed alveolar surfaces. Breaks up water and reduces surface tension. Type II alveolar cells also secrete a number of antimicrobial proteins that are important elements of innate immunity.
Which structure seals the larynx when we swallow?
The epiglottis seals the larynx when we swallow.
Which structural features of the trachea allow it to expand and contract, yet keep it from collapsing?
The incomplete, C-shaped cartilage rings of the trachea allow it to expand and contract and yet keep it from collapsing.
What features of the alveoli and their respiratory membranes suit them to their function of exchanging gases by diffusion?
The many tiny alveoli together have a large surface area. This and the thinness of their respiratory membranes make them ideal for gas exchange.
What are the layers of the pleural membranes?
The visceral pleura tightly adheres to the outside of lung, parietal pleura lines the pleural cavity and the space in between the is the pleural cavity.
Why does the pleural cavity have negative pressure?
Although the pleurae slide easily across each other, the surface tension of the pleural fluid strongly resists their separation. Consequently, the lungs cling tightly to the thorax wall and expand and recoil passively as the volume of the thoracic cavity alternately increases and decreases during breathing. (keeps the lungs expanded)
Describe the location of the lungs.
- The anterior, lateral, and posterior lung surfaces lie in close contact with the ribs and form the continuously curving costal surface.
- Just deep to the clavicle is the apex, the narrow superior tip of the lung.
The concave, inferior surface that rests on the diaphragm is the base.
What separates the lobes of the lungs?
Fissures
How many lobes does the right lung have?
3
What are the names of the fissures in the right lung?
horizontal fissure, oblique fissure
How many lobes does the left lung have?
2
What are/is the name(s) of the fissures in the left lung?
oblique fissure
What is the hilum?
An indentation through which pulmonary and systemic blood vessels, bronchi, lymphatic vessels, and nerves enter and leave the lungs. Each main bronchus plunges into the hilum on its own side and begins to branch almost immediately.
What are all of the structures within the hilum called?
the root