Unit Outcomes: The Blood, Cardiovascular, Lymphatic, and Immune Systems

Vocabulary practice flashcards covering the components and functions of the blood, cardiovascular system, lymphatic system, and immune system from the Unit Outcomes Test #2 review.

Blood

A body fluid that transports nutrients, gases (oxygen and carbon dioxide), hormones, ions, and waste products, while protecting against pathogens and preventing excessive blood loss.

Blood plasma

A pale yellow, mainly water-based fluid containing proteins that regulate fluid volume (albumin), protect against pathogens (antibodies), and prevent blood loss (clotting factors).

Serum

Blood plasma minus the clotting proteins.

Erythrocytes (RBCs)

Disc-shaped cells without a nucleus that contain hemoglobin to transport oxygen to tissues, live for approximately 120 days, and are recycled by the spleen.

Leukocytes (WBCs)

White blood cells comprising 5 main types (neutrophils, eosinophils, basophils, lymphocytes, monocytes) that protect the body against infection and harmful invaders by migrating into lymph tissue or sites of inflammation and infection.

Thrombocytes (Platelets)

Blood cell fragments that form a platelet plug in damaged blood vessels to initiate the clotting process.

Rh typing

A blood categorization system where blood is classified as Rh positive if red blood cells carry the Rh antigen, and Rh negative if they lack it.

Systemic circulation

The pathway that circulates blood from the left heart to body organs and back to the right heart.

Pulmonary circulation

The pathway that circulates blood from the right heart through the lungs and back to the left heart.

Hepatic portal circulation

The pathway that routes blood from digestive organs through the hepatic portal vein to liver sinusoids, then through hepatic veins into the inferior vena cava.

Myocardium

The muscular pumping layer of the heart.

Coronary arteries

Arteries (left and right coronary arteries) branching from the aorta that deliver oxygen-rich blood to the myocardium.

Coronary sinus

A vessel that receives deoxygenated blood drained by the coronary veins and empties directly into the right atrium.

Ischemia

Cell death caused by a blockage in the coronary arteries, presenting with symptoms such as stabbing chest pain and cramps, and potentially leading to myocardial infarction.

Atrioventricular (AV) valves

Heart valves located between the atria and ventricles (tricuspid and bicuspid/mitral) that keep blood flowing forward.

Semilunar valves

Heart valves located at ventricular exits (pulmonic and aortic) that maintain forward blood flow.

Heart conduction system

The specialized cardiac electrical route consisting sequentially of the SA node, AV node, Bundle of His, Right and Left Bundle Branches, and Purkinje fibers.

P wave

The electrocardiogram feature representing atrial depolarization.

QRS wave

The electrocardiogram feature representing ventricular depolarization.

T wave

The electrocardiogram feature representing ventricular repolarization.

Arteries

Deeper blood vessels with thicker walls and a prominent tunica media containing elastic tissue and smooth muscle designed to handle high pressure.

Veins

Blood vessels with a thinner smooth muscle layer that contain one-way valves in the tunica intima to prevent backflow and return blood to the heart.

Pulse

The rhythmic expansion and recoil of arteries corresponding to heart contractions.

Blood Pressure

The pressure exerted by blood on vessel walls, calculated as $\text{BP} = \text{Cardiac Output} \times \text{Systemic Vascular Resistance}$.

Systole

The contraction phase of the heart chambers, recorded as the top blood pressure number.

Diastole

The relaxation and filling phase of the heart chambers, recorded as the bottom blood pressure number.

Vasomotor center

A regulatory center in the medulla oblongata that receives sensory input from baroreceptors (in the aortic arch and carotid sinus) via cranial nerves IX and X, sending autonomic motor signals to modify heart rate and blood vessel diameter.

Lymph

A clear, pale yellow fluid composed primarily of water, electrolytes, metabolic waste, and proteins that have leaked out of blood capillaries into the interstitial tissue spaces.

Lymph nodes

Small, pea-shaped biological filters clustered along lymphatic vessels.

Tonsils

Partially encapsulated lymph nodes located in the throat, consisting of palatine and pharyngeal (adenoid) tissue.

Thymus gland

A lymphatic organ located in the thoracic mediastinum that secretes thymosins and supports T cell maturation.

Spleen

The largest lymphatic organ, situated in the upper left abdominal quadrant, containing white pulp (lymphoid tissue) and red pulp (which filters blood).

Non-specific (innate) immunity

Inborn defenses that react equally to all threats without developing immunological memory, serving as the first and second lines of defense.

Specific (adaptive) immunity

Acquired defense mechanisms that target tailored invaders and build long-term immunological memory, serving as the third line of defense.

Active immunity

A state of immunity created when the body actively produces its own antibodies or immune cells via infection or vaccination.

Passive immunity

Temporary immunity acquired by receiving pre-made antibodies from an external source, such as breast milk or immunoglobulins.

Antibodies

Immune proteins that neutralize antigens, opsonize pathogens for destruction, trigger agglutination, and activate complement.

Complement proteins

Proteins that lyse bacterial cell membranes, stimulate inflammation, and enhance phagocytosis.

Phagocytes

A category of immune cells comprising neutrophils, monocytes, and macrophages that ingest and digest pathogens.

Lymphocytes

White blood cells comprising T cells (helper, cytotoxic, suppressor, and memory cells) driving cell-mediated immunity, and B cells (differentiating into plasma and memory cells) driving humoral/antibody-mediated immunity.