Which action leads to the closure of the right atrioventricular valve?

Metabolically, cardiac muscle relies on

A drug that decreased calcium levels in a muscle cell and thereby lowered the number of crossbridges formed during the heart's contractions would be a

The shutting of the semilunar valves occurs during which phase?

During the plateau phase of a cardiac muscle cell's action potential, the membrane stays

The formation of a web-like polymer of fibrin occurs late in the ________ pathway.

Which events occur during the recycling of aged or damaged erythrocytes? (Order is not important.) a: The heme group is converted into biliverdin. b: Bilirubin is placed in long-term storage in the liver. c: The iron ions in hemoglobin are removed. d: The iron ions are stored in the liver. e: The iron ions are stored in the red bone marrow. f: Membrane proteins and globin proteins are broken down and reused. g: The erythrocyte contents, excluding the globins, are excreted unchanged via the digestive tract.

Plasma makes up about ________ percent of a centrifuged sample of whole blood.

Beta-globulins transport ________, whereas gamma-globulins are ________.

Which are functions performed by the fibrous skeleton of the heart? a: Separates the atria and ventricles b: Anchors the heart valves c: Provides electrical insulation between the atria and ventricles d: Provides the framework for the attachment of the myocardium e: None of these are true functions of the fibrous skeleton of the heart

Which are differences between cardiac muscle tissue and skeletal muscle tissue? a: The sarcoplasmic reticulum in cardiac muscle is less extensive. b: The sarcoplasmic reticulum in cardiac muscle is more organized. c: Cardiac muscle has intercalated discs; skeletal muscle does not. d: Cardiac muscle has 1 or 2 nuclei per cell; skeletal muscle has multiple nuclei per cell. e: Cardiac muscle has more well-defined terminal cisternae.

The term "epicardium" is another name for the

The opening and closing of the heart valves is caused by

Which circuit of the cardiovascular system is responsible for sending blood to the kidneys, stomach, and pelvic regions?

During the S-T segment, what is occurring within cardiac muscle cells?

Leukocytes are the ________ of the formed elements, and leukocytes have ________.

Vagal tone refers to the

Which carries oxygenated blood from the lungs to the heart?

The smallest and most abundant plasma proteins are the

During platelet plug formation, platelets begin to stick to

What is the sequence of events in the transmission of an impulse through the heart muscle? a: AV node b: AV bundle c: SA node d: Through the atria e: Through the ventricles f: Bundle branches g: Purkinje fibers

The papillary muscles attach to the cusps of the atrioventricular valves by means of the

Oxygen-poor blood is ________ in color.

The serous fluid within the pericardial cavity works to

Cardiac output is the amount of blood that is pumped

Typically, there are ________ papillary muscles that project from the wall of the left ventricle and attach to the tendinous cords that support the left AV valve.

During a cardiac cycle, how many of the four chambers contract at any one time?

Which depicts the order of cell formation in erythropoiesis? a: Proerythroblast b: Normoblast c: Myeloid stem cell d: Reticulocyte e: Erythroblast f: Mature erythrocyte `

Blood plasma is slightly ________; if pH drifts out of the normal range, dire consequences can result from alterations in the structure of ________.

Which type of leukocyte releases histamine?

The process of producing the formed elements of blood is called

Once an SA nodal cell reaches threshold, the depolarization phase occurs during which

If a patient becomes dehydrated, the percentage of plasma in a centrifuged sample of his or her blood would likely

During hemopoiesis, the lymphoid line forms lymphocytes only.

The type of leukocyte that will migrate in the blood and take up residence in the tissues as a macrophage is a(n)

The heart valves

Extensions from megakaryocytes that extend through blood vessel walls in red marrow are sliced off from the cells by the force of blood flow. These extensions are

Platelets play a key role in ________, but if they are not used they are broken down after about ________ days.

Prostacyclin is an eicosanoid that acts as a

Platelets are formed elements.

Which feature permits the compression necessary to pump large volumes of blood out of the ventricles?

Which leukocytes are derived from the myeloid line?

The viscosity of blood is ________ proportional to the number of erythrocytes and ________ proportional to the amount of fluid.

The reason it is more appropriate to call an erythrocyte a "formed element" rather than a "cell" is that erythrocytes

Old erythrocytes are phagocytized in the

Which term best describes the function of blood when considering the presence of leukocytes and antibodies?

If agglutination occurs after a blood transfusion, it may indicate

Which describes the endocardium? a: Has single layer of epithelium b: Has layer of areolar connective tissue c: Epithelial cells are squamous d: Epithelial cells are cuboidal e: Has layer of adipose connective tissue f: Has patches of myocardium

Sympathetic innervation of the heart a: increases the heart rate b: decreases the heart rate c: increases the force of contractions d: decreases the force of contractions e: has no effect on contraction force

Which type of muscle cell exhibits a longer refractory period?

A malnourished person might have abnormally low levels of plasma proteins. As a result, colloid osmotic pressure

An individual's hematocrit would vary with

The carbon dioxide molecules that bind to the hemoglobin molecule are attached to the ________ units.

An autorhythmic heart cell is one in which

One of the functions of blood is to regulate fluid levels in the body. If too much fluid escapes from the bloodstream and enters the tissues, blood pressure will

Which valve prevents the backflow of blood into the left ventricle when the ventricles relax?

The membrane of a contractile cardiac muscle cell contains

The function of the coronary sinus is to

`One of the unhealthy effects of blood doping is to

As blood is pumped out of the heart and into the major arteries leaving the