Cardiovascular System Lecture Notes

This set of practice flashcards covers blood composition, formed elements, blood grouping, heart anatomy, and the cardiac cycle based on the provided lecture notes.

What are the three primary functions of blood?

1. Transports oxygen, waste, and hormones. 2. Regulates body temperature, $pH$, and fluid volume. 3. Prevents infection and blood loss.

What are the percentages of plasma, white blood cells/platelets, and red blood cells in a sample of whole blood?

Plasma: $55\%$, White blood cells and platelets: $<1\%$, Red blood cells: $44\%$.

What is the specific $pH$ range of blood?

$7.35$ to $7.45$.

What are the names of the three basic types of proteins found in plasma?

Albumin, Globulins, and Fibrinogen.

How many oxygen molecules can a single hemoglobin molecule hold?

$4$ oxygen molecules ($O_2$), because it has $4$ globin chains each containing a heme group with an Iron atom.

How do leukocytes differ from erythrocytes in terms of their lifespan and nucleus?

Erythrocytes do not contain nuclei and live only $100$-$120$ days; Leukocytes always contain nuclei and most live only a few days, though some live for years.

What is the mnemonic device used to remember the relative commonality of leukocytes in order?

Never (Neutrophils) Let (Lymphocytes) Monkeys (Monocytes) Eat (Eosinophils) Bananas (Basophils).

Which leukocyte becomes a macrophage when it enters surrounding tissues to attack viruses and bacteria?

Monocytes.

What is the process of blood cell formation called, and where does it occur in adults?

Hematopoiesis; it occurs in the red bone marrow.

Which hormones stimulate the production of red blood cells, white blood cells, and platelets?

Red blood cells: erythropoietin; White blood cells: colony stimulating factors (CSFs) and interleukins; Platelets: thrombopoietin.

What is the difference between a thrombus and an embolus?

A thrombus is an abnormal clot that forms within a blood vessel; an embolus is a thrombus that has dislodged and floats through the blood.

Why is Rh antigen monitored during pregnancy if a mother is $Rh^-$ and the baby is $Rh^+$?

The mother's blood will develop anti-$Rh$ antibodies; RhoGam is used to prevent the mother's blood from attacking the baby.

What are the three layers of the heart wall, from superficial to deep?

Epicardium, Myocardium, and Endocardium.

What is the function of the pulmonary circuit compared to the systemic circuit?

The pulmonary circuit carries blood from the heart to the lungs and back (to pick up $O_2$); the systemic circuit carries blood from the heart to the rest of the body.

Which heart valves are located between the ventricles and the major blood vessels?

Semilunar valves (pulmonary valves on the right and aortic valves on the left).

In the intrinsic conduction system, what is the correct path of the electrical signal?

SA node $\rightarrow$ AV node $\rightarrow$ AV bundle $\rightarrow$ bundle branches $\rightarrow$ Purkinje fibers.

What formula is used to calculate cardiac output?

$Cardiac \, output = stroke \, volume \times heart \, rate$.

What are the three cell layers (tunics) found in both arteries and veins?

Tunica intima, Tunica media, and Tunica externa.

Why is it beneficial for capillaries to have only one cell layer?

It allows for a high diffusion rate so gas exchange can occur effectively between blood and surrounding tissues.

What structures in larger veins prevent the backflow of blood?

Valves.