Overview of Cardiovascular System Functions and Disorders

Arteries

Have mostly elastic and muscular walls that help them withstand high blood pressure.

Veins

Have thinner walls, which allow the return of deoxygenated blood under low pressure.

Capillaries

Have thin walls that allow the exchange of gas and nutrients.

Circulatory Shock

A failure of the cardiovascular system to deliver enough oxygen and nutrients to meet cellular metabolic needs.

Causes of Circulatory Shock

Loss of bodily fluids, dehydration, and severe burns.

Symptoms of Circulatory Shock

Cool pale skin, thirst, and nausea.

Treatments of Circulatory Shock

Give fluids, keep person warm, and give oxygen.

Erythropoietin (EPO)

Stimulates the process of red blood cell formation.

Antidiuretic Hormone

In response to dehydration or decreased blood volume, it causes vasoconstriction (narrowing of blood vessels) which increases blood pressure.

Foramen Ovale

An opening between the left and right atrium in the fetal heart that allows oxygen to bypass the lungs; after birth, it closes and turns into the fossa ovalis.

Ductus Arteriosus

A small trunk that connects the pulmonary trunk with the aorta in the fetal heart to allow blood to bypass the lungs; after birth, it closes and the fibrous remnant is the ligamentum arteriosum.

Varicose Veins

Bulging, enlarged veins caused by weakened valves in veins that cause backflow and buildup of blood.

Double-Circulatory System Advantages

No mixing of oxygenated and deoxygenated blood; allows for double pumping to the lungs and body tissue; works with the respiratory system to allow for the import of oxygen and the export of carbon dioxide.

Things Circulated by Blood

Gases (oxygen and carbon dioxide), nutrients (glucose and water), wastes, hormones.

Blood Pressure Readings

Two readings represent different pressures for different parts of the cardiac cycle; the first number is systolic blood pressure during ventricular contraction, and the second number is diastolic blood pressure during ventricular relaxation.

Arterioles Control Blood Pressure

By contracting or expanding to allow more or less blood through to control how forcefully blood moves through your body.

Factors Controlling Heart Rate

Chemicals (epinephrine increases hr and potassium + sodium decreases hr), temperature (warm temp increases hr and low temp decreases hr), sex (males have lower resting hr and females have higher resting hr).

Jobs of Blood

Transportation (gases, nutrients, etc.), regulation (helps regulate the pH of bodily fluids), protection (clots in response to injury which prevents extensive loss from the cardiovascular system).

ABO Blood Typing System - Type A

Has A antigens, has anti-B antibodies; can give blood to A and AB, can receive blood from A and O.

ABO Blood Typing System - Type B

Has B antigens, has anti-A antibodies; can give blood to B and AB, can receive blood from B and O.

ABO Blood Typing System - Type AB

Has A and B antigens, has no antibodies; can give blood to AB, can receive blood from A, B, O, and AB

ABO Blood Typing System - Type O

Has no antigens, has anti-A and anti-B antibodies; can give blood to A, B, AB, and O, can receive blood from O.

Rh Factor Reaction

When an Rh- person is exposed to Rh+ blood for the first time, no dangerous reaction happens; however, the Rh- person creates antibodies for Rh, so if exposed a second time, they will have a harmful reaction.

Blood Disorders - Anemia

When the O2 carrying capacity of blood is reduced.

Blood Disorders - Thalassemia

An inherited disorder where the body does not produce enough hemoglobin (the protein in RBCs that carries O2).

Blood Disorders - Hemophilia

A genetic disorder where blood does not clot properly due to a deficiency of clotting factors.

Blood Disorders - Leukemia

The overproduction of abnormal white blood cells that collect and drive out normal, healthy blood cells.

Blood Disorders - Hypoxia and Cyanosis

Hypoxia is when body tissues do not get enough O2; cyanosis is the bluish discoloration of the skin which is often a symptom of hypoxia.