Cardiovascular system Flashcards
The thick tunica media of muscular arteries and decreased quantity of elastic fibres limits what ability?
Their ability to expand
What are collateral arterial branches?
Branches that arise from the side of the main blood vessel
Briefly describe the role of the urinary system in the circulatory system
Delivers 20% of resting circulation to kidneys for filtering, reabsorption of useful products, and seretion of excesses - regulates blood volume and pressure by regulating fluid loss in the form of urine and by releasing the enzyme renin that is essential in the RAAS mechanism
A typical heart is approximately ____cm wide
8cm
Which arteries have a higher percentage of elastic fibres in all three tunics? What is the name for these vessels?
Those closest to the heart - they are known as elastic arteries
The posterior surface of the heart lies near the bodies of the ____.
Vertebrae
What kind of artery are the aortic collateral branches?
Elastic artery
From what does a macrophage develop?
A monocyte that has left circulation
The weight of a female heart is approximately ____ to ____ grams
250 - 300
Where do T lymphocytes mature?
Thymus
Name the single vessel that exits the right ventricle
Pulmonary trunk
Erythrocytes pick up approximately ____% of carbon dioxide waste at the tissues to transport to the lungs for exhalation
24%
Paired vertebral arteries join together to form the large basiliar artery at the base of which structure?
Medulla oblongata
What is the effect of veins having a larger diameter of the lumina?
More blood can flow with less vessel resistance
Do the chemicals released by basophils contribute to or inhibit inflammation?
Contribute, through the release of histamine
Name the two ‘great arteries’
Aorta and pulmonary trunk
What is a product/function of capillaries being extremely narrow in diameter?
It slows the passage of erythrocytes and extends the window of opportunity for gas exchange to occur
What percentage of leukocytes are made up of monocytes?
2 - 8%
Where are continuous capillaries found?
Almost all vascularised tissues
Some therapies are now using infusions of concentrated ____ to stimulate healing.
Platelets
Why are a third of platelets stored in the spleen?
They are released in response to blood vessel rupture
The inferior vena cava parallels the ____ ____.
Abdominal aorta
The diameter of muscular arteries typically ranges from ____mm to ____mm
0.1mm to 10mm
To what do coronary arteries supply blood?
The myocardium and other components of the heart
The left side of the heart is deflected ____.
Posteriorly
How many monocytes are present in 1µL of blood?
455
The space (note: not the cavity) where the heart is situated is known as the ____.
Mediastinum
From what and where do erythrocytes and leukocytes originate?
Haematopoietic stem cells in bone marrow
What is the most common leukocyte?
Neutrophils
Where are sinusoidal capillaries found? There are five possible answers.
Liver, spleen, bone marrow, lymph nodes, and endocrine glands including the pituitary and adrenal/supradrenal glands
The tunica intima is composed of ____ and ____ tissue layers.
Epithelial; connective
What is the primary function of erythrocytes?
To collect inhaled oxygen from the lungs and transpor it to the body’s tissues, and to pick up carbon dioxide waste from the tissues and transport it to the lungs for exhalation
Where do B lymphocytes mature?
Bone marrow
Where is the coronary sinus located?
Posteriorly in the atrioventricular sulcus, where it opens into the right atrium
From where does the inferior mesenteric vein receive blood?
Distal third of the large intestine including the descending colon, sigmoid colon, and rectum
Pulmonary capillaries surround lung strctures known as ____.
Alveoli
Name the large coronary vein that empties into the right atrium
The coronary sinus
The small lumen of arterioles allows them to serve what role in blood flow?
Slowing down/resisting blood flow and so causing a drop in blood pressure
The pulmonary veins conduct blood into the ____ ____.
Left atrium
The hepatic portal vein typically arises in the abdomen as a confluence of which two veins?
Superior mesenteric and splenic veins
After platelets enter circulation, appromately a third migrate to what location for storage?
The spleen
Name the three tissue layers of arteries and veins
Tunica intima (AKA tunica interna), tunica media, tunica externa (AKA tunica adventitia)
Do superficial veins usually have direct arterial counterparts?
No - deep veins usually have corresponding arteries
What is an arteriole?
A very small artery that leads to a capillary
The pericardium sits in its own space called the ____ ____.
Pericardial cavity
Approximately what percentage of leukocytes are lymphocytes?
20-30%
Eosinophils are phagocytic and particularly effective against ____-____ ____.
Antigen-antibody complexes
What is the purpose of the arterial elastic lamina?
To provide structure while allowing the vessel to stretch
How many basophils are present in 1µL of blood?
44
Many veins draining regions share a name with the arteries that supply that region - this is described as a ____ pattern.
Complementary
Do veins have an elastic lamina?
No, only arteries have the distinct layer of elastic fibres
Vessels larger than ____ in diameter are typically elastic arteries.
10mm
Name five subtypes of leukocyte
Neutrophil, eosinophil, basophil, lymphocyte, monocyte
Of neutrophils, eosinophils, and basophils, which has a usually 2-lobed nucleus that can be hard to see?
Basophils
What is the name of the valve leading to the pulmonary trunk?
The pulmonary semilunar valve
Of neutrophils, eosinophils, and basophils, which has granules that typically stain dark blue/purple?
Basophils
Do sinusoidal capillaries in the lymph nodes carry blood or lymph?
Lymph
The number of capillary fenestrations and their degree of permeability varies depending on their ____.
Location
The proper term for a red blood cell is an ____.
Erythrocyte
Why is the pericardial cavity filled with serous fluid?
To reduce friction between the heart and the pericardium
Why doesn’t the right ventricle require the same high pressures to pump blood as the left ventricle?
The pulmonary circuit is much shorter than the systemic circuit and therefore provides less resistance.
The ____ ____ artery terminally branches into internal and external carotid arteries
Common carotid
True or false: on leaving capillaries some leukocytes will assume fixed positions while others will move through tissues and still others will move towards chemical signals
True
Briefly describe the role of the skeletal system in the circulatory system
Provides calcium, posphate, and other materials critical for bone matrix; transports hormones regulating buildup and adbsorption of matric includling growth hormone, thyroid hormone, calcitonins, and parathyroid hormone; erythropoistin stimulates myeloid cell haematopoieses; some level of protection for selet vessels by bony structures
The ____ is continuous throughout the entire vascular system including the lining of the heart
Endothelium
What is the name of the left atrioventricular valve?
The bicuspid/mitral valve
High counts of monocytes are a possible indication of what? There are four possible answers.
Viral/fungal infections, tuberculosis, some forms of leukemia, and other chronic diseases
What is the meaning of the ‘termination’ of a blood vessel?
The point where blood leaves the named blood vessel
What is the appearance of eosinophils in a standard blood smear?
Bright red-orange granules; nucleus is generally two-lobed
What prevents backflow of blood into the left atria during ventricular contraction?
Closing of the bicuspid/mitral valve
Describe the structure of sinusoidal capillaries
Flattened, with extensive intercellular gaps and incomplete basal membranes as well as intercellular clefts and fenestrations
What is the purpose of a macrophage?
To phagocytose debris, foreign pathogens, worn-out erythrocytes, and many other dead/damaged/worn cells
Where does the aortic arch terminate?
Level with the intervertebral disk between the 4th and 5th thoracic vertebrae
Processed blood and systemic blood exit the liver via the ____ veins and flows into the ____ ____ ____.
Hepatic; inferior vena cava
Do erythrocytes move in and out of the blood vessels or do they remain within the vascular network?
Leukocytes typically leave the vessels for defensive functions, but it is abnormal for erythrocytes to do so
What structural features characterise continuous capillaries?
Complete endothelial lining with tight junctions between endothelial cells
Name the three vessels that originate from the aortic arch
Brachiocephalic trunk, left common carotid artery, left subclavian artery
One of the most distinctive characteristics of leukocyte activity is their ____.
Movement
Arteries further from the heart with less elastic fibres and more smooth muscle are described as a ____ artery.
Muscular
The proportions of smooth muscle cells and elastic fibres in the tunica media vary depending on what factor?
Distance from the heart
The external carotid artery supplies blood to which structures?
Numerous structures within the face, lower jaw, neck, oesophagus, and larynx
What is the purpose of the systemic circuit?
To transport oxygenated blood to the tissues of the body and return relatively deoxygenated blood and CO2 to the heart to be sent back into the pulmonary circuit
Which veins are usually the largest entering the inferior vena cava?
Renal veins
Briefly describe the role of the integumentary system in the circulatory system
Carries clotting factors, platelets, and WBC for haemostasis, fight infection, and repairing damage; regulates temperatures by controlling blood flow to the surface where heat can be dissipated; provides some colouration of integument; acts as a blood reservoir
The basal lamina provides ____ while maintaining ____.
Strength; flexibility
What is the general lifespan of eosinophils?
Minutes to days
Larger arteries have what structure at the boundary between tunica intima and tunica media?
A thick distinct layer of elastic fibres known as the internal elastic lamina (or internal elastic membrane)
The left and right sides of the heart each have one ____ and one ____ (chambers).
Atrium; ventricle
How many lymphocytes are present in 1µL of blood?
2185
The inferior mesenteric artery arises approximately ____cm to the common iliac arteries
5cm
What are the smallest arteries called?
Arterioles
Human bodies need blood to deliver ____ and remove ____.
Nutrients; wastes
What is the second most common type of leukocyte?
Lymphocyte
What is the purpose of valves in the cardiovascular system?
To ensure the flow of blood is one-way.
Another way to phrase this answer is ‘to prevent back-flow of blood’
The brachiocephalic trunk is located only on the ____ side of the body
Right
The splenic vein is formed from branches from which sources?
Spleen, pancreas, portions of the stomach, and the inferior mesenteric vein
From what type of cell do monocytes originate?
Myeloid stem cells
What is the purpose of memory cells?
To increase responses to subsequent exposures
The elastic recoil of the vascular wall helps maintain the ____ ____ that drives the blood through the arterial system
Pressure gradient
How do leukocytes migrates from venules or capillaries into tissues?
By squeezing through adjacent endothelial cells to enter tissue fluid
High counts of eosinophils are a possible indication of what? There are three possible answers.
Allergies, parasitic worm infestation, and some autoimmune diseases
Multiple venules join to form ____.
Veins
How do veins typically appear - rounded or flat?
Flattened
The tunica media of arterioles is how many smooth muscle cell layers thick?
One or two
What occurs in the alveoli?
Oxygen and gas exchange
Where does the ascending aorta become the aortic arch?
After moving in a superior direction for ~5cm the ascending aorta turns in an arc to the left and becomes the aortic arch
True or false: arteries generally have thick walls and wide lumens which allow for greater blood volume
False - arteries do have thick walls, but have small lumens which help maintain the pressure in systemic circulation
Why is a biconcave shape beneficial to erythrocytes over a spherical shape?
Relative to cell volume a biconcave shape has a greater surface area for gas exchange than a spherical shape
The common iliac arteries provide blood to which areas of the body?
The pelvic region and lower limbs
The thick tunica media of muscular arteries allows them to play a leading role in ____.
Vasoconstriction
Each gonadal artery supplies blood to the reproductive organs and is known as either an ____ artery or ____ artery depending on the sex of the individual.
Ovarian; testicular
Lymphocytes are primarily involved in ____ immunity
Specific/adaptive immunity
The inferior mesenteric artery supplies blood to which organs?
The distal segment of the large intestine, including the rectum
What component of blood arises from lymphoid stem cells?
Lymphocytes
Which type of cells and muscle fibres predominate in the arterial tunica media?
Smooth muscle cells and elastic fibres
What is the term for the layer of simple squamous epithelium lining the tunica intima?
Endothelium
Name the blood vessels where gas exchange occurs in the lungs
Pulmonary capillaries
What prevents backflow of blood into the right atria during ventricular contraction?
Closing of the tricuspid valve
Which chambers of the heart act as receiving chambers?
The left and right atria
The anterior surface of the heart sits deep to the ____ and ____ ____.
Sternum; costal cartilages
Arterioles are also known as ____ vessels.
Resistance
What is the size range of a venule diameter?
8 to 100µm
A typical heart is approximately ____cm thick
6cm
What is a patent foramen ovale?
A hole between the atria of an adult’s heart that didn’t close after birth to form the fossa ovalis
What is the function of basophils?
Promotes inflammation
Continuous capillaries in the brain are part of what structure?
The blood-brain barrier
Describe the tunica media of veins
Normally thinner than the tunica externa; smooth muscle cells and collagenous fibres predominate; nerves and vasa vasorum present; no external elastic membrane
What is a platelet (structure)?
A fragment of megakaryocyte cytoplasm that is surrounded by a plasma membrane
What is the purpose of the portal system delivering blood to the liver?
The liver processes the blood to remove certain wastes and excess nutrients which are stored for later use
The granules of eosinophils contain ____ which counteracts chemicals produced by basophils and mast cells
Antihistamine
The subclavian vein forms a confluence with the internal jugular vein to form the ____ vein.
Brachiocephalic
Do red blood cells have a nucleus?
No
Where might fenestrated capillaries be found (excluding the small intestine and kidneys)?
Choroid plexus of the brain and many endocrine structures including hypothalamus, pituitary, pineal, and thyroid glands
Each of the major pumping chambers of the heart ejects approximately ____mL blood per contraction in a resting adult
70mL
After gas exchange, oxygenated blood flows from pulmonary capillaries into pulmonary venules that lead to a series of ____ ____.
Pulmonary veins
True or false: the right and left ventricles pump the same volume of blood per contraction.
True. The left ventricle pumps at a high pressure, but the volume is the same.
Which is thicker, the interatrial septum or the interventricular septum? Why?
Interventricular septum, because the ventricles are required to generate greater pressures for contraction
Is the tunica externa of venules thick or thin?
Thin
Which are the primary pumping chambers of the heart?
The right and left ventricles
Name two organs in which fenestrated capillaries are common
Small intestine (primary site of nutrient absorption) and kidneys (blood filtering)
Briefly describe the process of circulation in the systemic capillaries
Oxygen and nutrients exit the systemic capillaries to be used by cells in metabolic processes, and carbon dioxide and waste products enter the blood
Which fibres are present in the arterial tunica externa?
Collagenous and elastic fibres
The descending aorta passes through the ____ diaphragm.
Thoracic
Initial lymphocytes originate in ____ ____.
Bone marrow
The lack of organelles in erythrocytes allows for the presence of ____ molecules
Haemoglobin
Venules go on to form larger ____.
Veins
The common iliac artery branches into the pelvis to form a vessel that passes deep to the inguinal ligament - this artery is known as the ____ artery.
Femoral
Macrophages release ____ and ____ chemicals that attract other leukocytes to the site of an infection.
Antimicrobial; chemotatic
Neutrophils, eosinophils, and basophils are all what category of leukocyte?
Granulocytes
What is the least common capillary subtype?
Sinusoidal capillaries
The right gonadal vein empties directly into the ____ ____ ____.
Inferior vena cava
Which muscle type and fibres are present in the venous tunica externa?
Smooth muscle and collagenous fibres
Is blood flow through sinusoidal capillaries fast or slow?
Very slow
The gonadal arteries arise ____ to the renal arteries and are generally ____ (cavity location)
Inferior; retroperitoneal
The pulmonary trunk leads toward the ____ and bifurcates into which two vessels?
Lungs; left and right pulmonary arteries
Are agranular leukocytes completely deficit of granules?
No - agranulocytes are not completely lacking in granules but they are far fewer and much less obvious.
Of neutrophils, eosinophils, and basophils, which has a nucleus with 2-5 lobes that increase with age?
Neutrophils
When does the abdominal aorta terminate?
When it terminally branches into the two common iliac arteries
From were does the superior mesenteric vein receive blood?
Small intestine, two-thirds of the large intestine, and stomach
List some substances that can pass between cells
Metabolic products such as glucose, water, small hydrophobic molecules like gases and hormones, as well as various leukocytes
The aorta divides at approximately L4 into which paired arteries?
Left and right common iliac artery
The hepatic portal vein receives blood from which organs?
Stomach, small intestine, large intestine, and spleen
Cardiac veins drain the heart and form tributaries into the ____ ____.
Coronary sinus
What do megakaryocytes do over time?
Form platelet-precursor extensions that extend through the bone marrow capillary walls to release thousands of cytoplasmic fragments each enclosed with plasma membrane into circulation - these are platelets
True or false: some superficial veins have no arterial counterpart
True
What is the purpose of venous valves?
To prevent backflow of blood
What is the meaning of the ‘origin’ of a blood vessel?
The point where blood first enters the blood vessel
In which are nerves and vasa vasorum present, arterial tunica media or arterial tunica externa?
Arterial tunica externa
The left coronary artery distributes blood to which structures?
The left side of the heart, left atrium and ventricle, and the interventricular septum
When do memory cells form?
After exposure to a pathogen
The right side of the heart is deflected ____.
Anteriorly
What lines the tunica intima?
A layer of specialised simple squamous epithelium
What is the function of platelets?
Haemostasis, repair of blood vessels when damaged, and release of growth factors for tissue repair
What is a lumen?
A hollow passageway in a vessel through which blood flows
The middle layer of muscle in the heart is called the ____.
Myocardium
Where are monocytes produced?
Red bone marrow
How do platelets appear in a standard blood smear?
As cellular fragments surrounded by a plasma membrane and containing granules; purple stain
The left gonadal vein is a tributary to the ____ vein which then empties into the inferior vena cava
Renal
What is an important characteristic of the basal lamina?
The basal lamina is permeable, allowing materials to pass through it
What must capillary walls allow if they are to function?
Allow substances to pass through
Name the septum between the ventricles
Interventricular septum
Which is a characteristic of the liver’s blood supply?
It is received from two sources - normal systemic circulation via the common hepatic artery and through the hepatic portal vein
When might an artery or vein change names/how it is referred to?
Vessel names can change with location, for example when they pass through an intersection or after passing an anatomical landmark
Name the three branches that arise from the abdominal aorta
Coeliac trunk, superior mesenteric artery, and inferior mesenteric artery
What is the size range of a monocyte?
12 - 20µm
What is the appearance of lymphocytes in a standard blood smear?
Spherical cells with a single nucleus often occupying most of the cell’s volume; stains purple; seen in large (natural killer cells) and small (B and T cells) variants
What is the general purpose of leukocytes?
To protect the body from invading microorganisms and body cells with mutated DNA, and cleaning up debris
Of neutrophils, eosinophils, and basophils, which has granules that typically stain brain red-orange?
Eosinophils
What is the appearance of monocytes in a standard blood smear?
Largest leukocyte with an indented or horseshoe-shaped nucleus
What would result if artery walls were rigid and unable to expand and recoil?
Their resistance to blood flow would gradually increase and blood pressure would rise to higher levels. The heart would be required to pump harder to increase the volume of blood and maintain adequate pressure and flow, forcing artery walls to become even thicker in response
Briefly describe the passages of oxygen and carbon dioxide in capillaries
Oxygen is carried by erythrocytes, diffuses into the plasma, then through capillary walls to reach the cells. Carbon dioxide is produced by the cells as waste and diffuses into capillaries to be picked up by erythrocytes
What are the purposes of the structural proteins in erythrocytes?
To maintain their unique structure and allow them to change shape to squeeze through capillaries
What is the purpose of the antimicrobial and chemotatic chemicals released by macrophages?
To attract other leukocytes to the site of infection
What is the name of the fat-filled grooves along the superior surfaces of the heart?
Sulci (singular: sulcus)
Erythrocytes rely on ____ respiration.
Anaerobic
Why are tight junctions between endothelial cells in capillaries different from other tight junctions?
Tight junctions are usually impermeable allowing only water and ions passage, however in capillaries they are often incomplete and leave clefts that allow for exchange of water and small molecules between blood plasma and interstitial fluid
Describe the appearance of the tunica intima of arteries
Endothelium usually appears wavy, and internal elastic membrane is present in larger vessels
The heart is separated from other structures in the mediastinum by the ____.
Pericardium
What comprises the wall of a capillary?
The endothelial layer surrounded by a basal membrane with occasional smooth muscle fibres
The fossa ovalis can be viewed ____ (direction) on the interatrial septum of the right atrium
Medially
Veins that join a major vein are known as ____.
Tributaries
What is the size range of a megakaryocyte?
50 - 100µm
Which type of cells and fibres predominate in the venous tunica media?
Smooth muscle cells and collagenous fibres
The descending aorta passes through an opening in the thoracic diaphragm known as the ____ ____.
Aortic hiatus
Each renal artery branches approximately ____cm inferior to the superior mesenteric arteries and supplies a kidney
2.5cm
The inferior vena cava drains blood from regions inferior to the ____ ____.
Thoracic diaphragm
As the pulmonary trunk reaches the superior surface of the heart it curves posteriorly and terminally branches into a left and right ____ ____.
Pulmonary artery
T lymphocytes perform what function in cellular immunity?
T cells directly attack other cells
Which are more rounded in appearance in cross section, arteries or veins?
Arteries
What is the purpose of the continuous capillary structures in the blood-brain barrier?
The structures combine to prevent the movement of nearly all substances
How does the pericardial cavity reduce friction between the heart and pericardium during cardiac contractions?
It is filled with lubricating serous fluid
True or false: veins have thin walls and large lumens.
True
What is the approximate lifespan of an erythrocyte?
120 days
Wht are the components of the thin outer layer of the tunica intima?
A small amount of areolar connective tissue consisting primarily of elastic fibres and some collagenous fibres.
Platelets are critical to ____ following damage to a vessel.
Haemostasis, the stoppage of blood flow
What do capillary fenestrations allow?
They make the capillary permeable to larger molecules
Explain why the liver requires extensive specialised sinusoidal capillaries
To process the materials brought by the hepatic portal vein from both the digestive tract and spleen, and to release plasma proteins into the circulation
Name the two significant paired arteries that arise from the abdominal aorta
Renal and gonadal arteries
Why is the atrioventricular sulcus significant?
It is the location of the coronary arteries
Describe the appearance of the tunica intima of veins
Endothelium appears smooth; there is no internal elastic membrane
Briefly describe the role of the endocrine system in the circulatory system
Delivers hormones; ANH, adrenaline, angiotensin II, ADH, thyroxe, and eostrogen
What occurs with the atria just prior to ventricular contraction?
The atria contract and actively pump blood into the ventricles.
How do erythrocytes appear in a standard blood smear?
As a flattened biconclave disk with no nucleus, pale red in colour
What is the size range of a platelet?
2 - 4µm
What is the vertebral artery?
A branch of the subclavian artery which passes through the vertebral foramen in the cervical vertebrae and then the foramen magnum into the cranial cavity to supply blood to the brain and spinal cord
The generic term for the valves between the atria and ventricles is the ____ valves.
Atrioventricular
What is the general lifespan of a neutrophil?
Minutes to days
How do arteries generally appear - rounded or flat?
Rounded
What is a fenestrated capillary?
A capillary that has pores (or fenestrations) as well as tight junctions in the endothelial lining
What is the primary function of platelets?
To limit blood loss
Muscular arteries in turn branch to distribute blood to the network of ____.
Arterioles
What is meant by ‘the great vessels’ of the heart?
‘Great vessels’ refers to the major arteries and veins that carry blood directly to and from the heart
B lymphocytes perform what function in humoral immunity?
B cells release antibodies
Attraction of leukocytes occurs through ____ ____.
Positive chemotaxis (‘movement in response to chemicals’)
What is the name of the aorta inferior to the thoracic diaphragm?
The abdominal aorta
What are auricles?
Relatively thin-walled structures that can fill with blood and empty into the atria
From where do B and T lymphocytes get their names?
From their location of origination - B cells mature in bone marrow, and T cells mature in the thymus
In addition to returning blood, superficial veins contribute to the maintenance of ____ ____.
Body temperature
What is the name of the right atrioventricular valve?
The tricuspid valve
The left subclavian artery and left common carotid arteries arise independently from the ____ ____.
Aortic arch
High counts of lymphocytes are a possible indication of what? There are two possible answers.
Viral infections and some types of cancer
Name the great vessels of the heart
Superior vena cava, inferior vena cava, aorta, pulmonary trunk, pulmonary veins
The right and left brachiocephalic veins confluence to form which major vessel?
Superior vena cava
How do neutrophils appear in a standard blood smear?
As pale lilac granules; nuclear lobes increase with age
Where and how are platelets produced?
Platelets are formed from megakaryocytes that stay in red bone marrow and shed platelets into circulation
The superior vena cava drains blood from regions superior to the ____ ____.
Thoracic diaphragm
Low counts of lymphocytes are a possible indication of what?
Prolonged chronic illness or immunosuppression, including that caused by HIV infection and steroid therapies
What are the three major types of lymphocytes?
T cells, B cells, and natural killer cells
How many neutrophils are present in 1µL of blood?
4150
Explain why sinusoidal capillaries are vital - use bone barrow as an example.
When bone marrow forms new blood cells, the cells must enter the blood supply and can only do so through the large openings of a sinusoidal capillary; they cannot pass through the small openings of continuous or fenestrated capillaries
Why must the left ventricle generate a higher pressure?
To overcome the high resistance required to pump blood into the extensive systemic circuit.
How many erythrocytes are present in 1µL of blood?
5.2 million
Highly oxygenated blood returning from the pulmonary capillaries passes through a series of vessels that join together to form the ____ ____.
Pulmonary veins
A muscular artery is also known as a ____ artery.
Distributing
After leaving circuation monocytes are called ____.
Macrophages
True or false: there is a great deal more variability in the venous circulation than normally occurs in the arteries
True
When does most ventricular filling occur?
When the atria are relaxed
How long do platelets remain before they are phagocytosed by macrophages?
Approximately 10 days
Describe the location of the inferior vena cava
Deep to the parietal peritoneum in the abdominal cavity in the retroperitoneal compartment
The auricles are also known as ____ ____.
Atrial appendages
What is the function of the basal lamina?
Binds the endothelium to the connective tissue
Natural killer cells are similar to ____ ____ (type of cell) but are nonspecific.
T cells/lymphocytes
Which type of cell is active in humoral immunity?
B cells
What is unique about the pulmonary veins?
They are the only veins that carry highly oxygenated blood
The internal jugular vein carries blood from which location?
Cranial cavity
What is a capillary?
A microscopic channel that supplies blood to tissues via perfusion
What are vasa vasorum?
The network of small blood vessels that supply the walls of large vessels (these vessel walls are muscle and need nutrients too) such as the aorta and vena cavae.
Slow blood flow through sinusoidal capillaries allows more time for what?
Exchange of gases, nutrients, and wastes
The brachiocephalic trunk terminally branches into which two arteries?
Right subclavian artery and right common carotid artery
What is the function of the coronary sinus?
The coronary sinus drains the myocardium
What is the appearance of basophils in a standard blood smear?
Heavy, dense, dark purple granules; nucleus generally two-lobed but can be difficult to see
In comparison to arteries, venules and veins withstand a much ____ pressure from the blood flowing through them
Lower
Which has smaller lumina, arteries or veins? Why?
Arteries, because it helps maintain the pressure of blood moving through the system
Briefly describe the role of the nervous system in the circulatory system
Produces CSF within choroid plexuses; contributes to blood-brain barrier; caridac and vasomotor centres regulate cardiac output and blood flow through vessels via an automatic system
Why don’t red blood cells have a nucleus?
So they can more efficiently carry oxygen and carbon dioxide while still being able to fit through extremely small spaces
Briefly describe the role of the muscular system in the circulatory system
Provides nutrients and oxygen for contraction; removes lactic acid and distributes heat generated by contraction; muscular pumps aid in venous return; exercise contributes to cardiovascular health
Granular leukkocytes typically have a ____ nucleus.
Lobed
Describe the location of the abdominal aorta
Left of the vertebra column, embedded in adipose tissue posterior to the peritoneal cavity in the retroperitoneal compartment
Low counts of monocytes are a possible indication of what?
Bone marrow suppression
True or false: all vessels have a mirrored pair on the opposite side of the body
False - some vessels such as the aorta and vena cavae are unique
High counts of neutrophils are a possible indication of what?
Infection and/or inflammation
Eosinophils release ____.
Antihistamines
Positive chemotaxis occurs in response to chemical signals released by what?
Injured or infected cells
The deep sulcus between the atria and ventricles is called the ____ ____.
Atrioventricular sulcus
Why do erythrocytes rely on anaerobic respiration?
They lack mitochondria and cannot produce their own energy
What stain is best used for see eosinophil granules?
An acidic stain called eosin
In which layer/s of the venous tunica externa are nerves and vasa vasorum present?
Tunica media and tunica externa
What prevents backflow of blood into the left ventricle after it is pumped into the ascending aorta?
Closing of the aortic semilunar valve
The left ventricle pumps blood into the aorta and onwards into the ____ circuit.
Systemic
Why do arteries and arterioles have thicker walls than veins and venules?
They are closer to the heart and receive blood that is surging at a far greater pressure
Briefly describe what would occur if a monocyte comes to a site of infection through positive chemotaxis
The monocyte exits the capillary to move toward the most concentrated chemical signals, differentiates into a macrophage, and proceeds to phagocytose the pathogens
A typical heart is approximately ____cm in length
12cm
The average arteriole lumen is ____µm or less in diameter.
30µm
Atrial contraction just prior to ventricular contraction accounts for approximately ____% of ventricular filling.
20%
Do venules have values to prevent backflow of blood?
No, only veins have valves
The human heart is located medially to the ____.
Lungs
Describe the tunica media of arteries
Normally the thickest layer in arterial tissue; smooth muscle cells and elastic fibres; external elastic membrane present in larger vessels
What prevents backflow of blood into the right ventricle after it is pumped into the pulmonary trunk and intro right and left pulmonary arteries?
Closing of the pulmonary semilunar valve
What is the approximate size range of a lymphocyte?
6-17µm
What is the general purpose of heparin?
Opposes blood clotting
The subclavian vein carries blood from which location?
Upper limbs
The diameter of a capillary lumen ranges from ____ to ____µm
5 to 10µm
How many chambers are in the human heart?
Four
Of neutrophils, eosinophils, and basophils, which has granules that typically stain lilac?
Neutrophils
The internal carotid artery initially forms an expansion known as the ____ ____.
Carotid sinus
The granules of basophils release ____ and ____.
Histamines; heparin
Do macrophages assume fixed locations or wander through tissue fluid?
Both - some remain fixed, others move.
Briefly describe what would occur if a neutrophil comes to a site of infection through positive chemotaxis
The neutrophil exits the capillary to move toward the most concentrated chemical signals, releases chemicals from its granules that break apart pathogens, and may undergo phagocytosis
Briefly describe the role of the reproductive system the circulatory system
Aids in erection of genitalia in both sexes suring sexual arousal; transport gonadotropic hormones that regulate reproductive functions
Describe the location of the great saphenous vein
Prominent surface vessel on the medial surface of the leg and thigh
What is beside the endothelium in the tunica intima?
The basal lamina (AKA basement membrane)
In wider vessels erythrocytes may sometimes perform what action?
Stack up to form a rouleaux (like a roll of coins; French term for ‘roll’)
How porous are sinusoidal capillaries?
Extremely porous - sinusoidal capillaries have very large openings that allow passage of the largest molecules including plasma proteins and even cells
What is contained in the carotid sinus?
Carotid baroreceptors and chemoreceptors, both critical to maintaining cardiovascular homeostasis
The superior and inferior vena cavae return blood to the ____ atrium.
Right atrium
How many eosinophils are present in 1µL of blood?
165
What differs in the structure of the continuous capillaries in the blood-brain barrier in comparision to general body tissues?
The tight junctions do not have intercellular clefts, and there is a thick basal membrane as well as astrocyte extensions (called end feet)
Neutrophils release ____ chemicals from granules
Cytotoxic
Arterioles further branch into ____.
Capillaries
There are typically ____ (number) pulmonary veins
Four
Why does the endothelium in arterial tunica intima appear wavy?
The wavy appearance is due to the constriction of smooth muscle
What are the two categories of arterial branches?
Collateral and terminal branches
Name the two ‘great veins’
Superior and inferior vena cavae
Which layer of muscle tissue in the heart is the thickest?
Myocardium
The weight of a male heart is approximately ____ to ____ grams
300 - 350
The presence of venous valves is extremely important - why?
Blood flow becomes very sluggish in the extremities due to lower pressure and gravity
What is the function of the collagenous fibres in the outer layer of the tunica intima?
To provide the vessel with additional strength
Which is the least common leukocyte?
Basophils
What is unique about the pulmonary trunk and their branches?
They are the only arteries that carry relatively deoxygenated blood
Describe the purpose of the pulmonary circuit
To transport blood to and from the lungs to pick up oxygen and deliver carbon dioxide
In what alternative situations might a neutrophil count be elevated?
Patients with burn injuries or unusually high stress
The myocardium is composed primarily of ____ ____ cells.
Cardiac muscle
Name the three major collateral branches of the aortic arch
Brachiocephalic trunk, left common carotid artery, and left subclavian artery
What is the mean diameter of erythrocytes?
7-8µm
From where does the great saphenous vein collect blood?
The superficial portions of the medial surface of the leg and thigh
Which type of cell is active in cellular-level immunity and physically attacks foreign or diseased cells?
T lymphocytes
What are the three components of the cardiovascular system?
The heart, blood, and vessels
What is the function of the elastic fibres in the outer layer of the tunica intima?
To provide the vessel with additional flexibility
Two coronary arteries branch from the ascending aorta just superior to the aortic semilunar valve - what are they called?
The left and right coronary arteries
What is the proper term for a white blood cell?
Leukocyte
Briefly describe the role of the repsiratory system in circulatory system
Provides blood for critical exchange of gases to carry oxygen needed for metabolic reactions and carbon dioxide generated as byproducts of these processes
Neutrophils are phagocytic and particularly effective against ____.
Bacteria
Briefly describe the role of the digestive system in the circulatory system
Absorbs nutrients and water; delivers nutrients to liver for processing by hepatic portal vein; provides nutrients essentual for haematopoiesis and building haemoglobin
What is the root of the term ‘vasa vasorum’?
Latin - ‘the vessels of the vessels’
There is a superficial extension of each atria near the superior surface of the heart - what are they called?
Auricles
The number of eosinophils increases in ____ and ____ ____ (conditions)
Allergies; parasitic infections
What ability is afforded elastic arteries by the abundant elastic fibres?
They are able to expand as blood from the ventricles is pumped through them, and can recoil afterward
The right ventricle pumps blood into what structure?
Pulmonary trunk
What is the general lifespan of lymphocytes?
Years
Name the three components of the aorta
Ascending aorta, aortic arch, and descending aorta
The coeliac trunk supplies blood to which structures?
Stomach, spleen, liver, and several other supracolic organs
Veins that form from multiple smaller veins are called a ____.
Confluence
If a blood vessel changes names as it passes a landmark it is known as a _____.
Continuation
Capillary subtypes differ based on what property?
Permeability
Briefly describe what would occur if an eosinophil comes to a site of infection through positive chemotaxis
The eosinophil exits the capillary to move toward the most concentrated chemical signals, releases chemicals from its granules that break apart pathogens, and may undergo phagocytosis
What is perfusion (in the context of circulation)?
Exchange of gases and other substances in the capillaries between the blood and the surrounding cells and their tissue fluid
Secondary production of lymphocytes occurs in what location?
Lymphatic tissue
Rather than directly entering circulation, absorbed nutrients and certain wastes travel to the liver via the ____ ____ system.
Hepatic portal
What is the most common capillary subtype?
Continuous capillary
The contraction of the heart develops the pressure that ejects blood into the ____ and ____ ____.
Aorta; pulmonary trunk
Name the structure between the atria.
The interatrial septum
What structure do many veins have that arteries do not?
Valves
Is the muscle development the same for both sides of the heart?
No. The myocardium of the left ventricle is thicker and better developed than that of the right ventricle because it is required to generate higher pressures.
Which type of leukocyte produces antibodies that bind to specific foreign or abnormal components of plasma membranes?
B lymphocytes
Capillaries unite to form ____.
Venules
Do arterioles have the same three tunics as arteries?
Yes, though the thickness of each is greatly diminished
What defining feature shows where an elastic artery becomes a muscular artery?
None - there is no ‘line of demarcation’ or sudden change, only a gradual transition as the vascular tree repeatedly branches
Which veins generally correspond to the complementary arteries, deep or superficial?
Deep
The right coronary artery distributes blood to which structures?
The right atrium and portions of both ventricles
There are two distinct but linked circuits in human circulation - the ____ and the ____ circuits.
Pulmonary; systemic
Describe the tunica externa of arteries
Normally thinner than the tunica media (in all but the largest arteries); collagenous and elastic fibres; nerves and vasa vasorum present
Which types of blood vessels are the primary sites for leukocyte migration from blood into tissues?
Venules and capillaries
True or false: erythrocytes make use of the oxygen they themselves transport for their own cellular processes.
False - erythrocytes rely on anaerobic respiration
The superior mesenteric artery branches into several large major vessels that supply blood to which organs?
Small intestine, pancreas, and most of the large intestine
Briefly describe the role of the lymphatic system in the circulatory system
Transports various WBC incuding those protected by lymphatic tissue, and immuniglobulins (antibodies) throughout the body to maintain health; carries excess tissue fluid not able to be absorbed by the vascular capillaries back to the lymphatic system for processing
What is the function of monocytes?
Effective phagocytic cells as well as antigen-presenting cells (APCs) for other immune system components
Name the three subtypes of capillaries
Continuous, fenestrated, and sinusoidal
How many platelets are typically present in 1µL of blood?
150 000
The left ventricle pumps blood through the ____ ____ valve.
Aortic semilunar valve
What is the name of the aorta just superior to the thoracic diaphragm?
The thoracic aorta
What feature is found in the interatrial septum in adults?
An oval-shaped depression called the fossa ovalis
Why do arteries appear more rounded than veins in cross sections?
They have thicker walls and smaller diameters
What is the name of the valve leading to the ascending aorta?
The aortic semilunar valve
What is the fossa ovalis?
A remnant of an opening in the foetal heart called the foramen ovale.
The superior mesenteric artery arises approximately ____cm inferior to the coeliac trunk
2.5cm
The left atrium pumps blood through the ____ ____ into the left ventricle
Mitral/bicuspid valve
Further from the heart the percentage of ____ ____ in an artery’s tunica intima decrease and the amount of ____ ____ in the tunica media increases
Elastic fibres; smooth muscle
Lymphocytes and monocytes are both what category of leukocyte?
Agranulocytes
Describe the tunica externa of veins
Normally the thickest layer in veins; smooth muscle and collagenous fibres predominate; nerves and vasa vasorum present
The left ventricle pumps blood through the aortic semilunar valve into the ____.
Aorta
Vessel pairs - arteries and veins that share the same names parallel to one another throughout the body and are very similar on both sides - will be traced only through one ____ of the body
Side
High counts of basophils are a possible indication of what? There are three possible answers.
Allergies, parasitic infection, and hypothyroidism
Erythrocytes are estimated to make up approximately ____% of the total cells in the body.
25%
The human heart is located within the ____ cavity.
Thoracic
Where are megakayocytes located?
Bone marrow
The inferior vena cava is formed at L5 from the confluence of which paired veins?
Common iliac veins
How do venous valves form?
Sections of thickened endothelium are reinforced by connective tissue and extend into the lumen
What are terminal arterial branches?
Branches where the named vessel ends and branches into two other vessels
