Chapter 2: Body Systems

What are the 3 layers of the heart?

1. Endocardium: Innermost layer of heart that is made up of a single layer of endothelial cells that line the chambers and valves

2. Myocardium: Middle muscular layer of heart that is made up of contractile tissue and creates the pressure necessary to pump blood

3. Epicardium: Fibrous outer layer of heart that covers and protects

What is oxygenated blood and it flows from what to what?

Oxygen rich blood that flows from lungs to body

What is deoxygenated blood and it flows from what to what?

Oxygen deficient blood that flows from body to lungs

What is pulmonary circulation?

• Heart → lungs → heart

• Blood travels to lungs where gas exchange taks place in alveoli

• CO2 is exchanged for O2

What is systemic circulation?

Heart → body

What are veins?

Blood vessels that carry deoxygenated (usually) blood toward the heart

What are arteries?

Blood vessels that transport oxygenated (usually) blood away from the heart

What are capillaries?

Smallest blood vessels that exchange oxygen, nutrients, and waste

What makes up whole blood?

• Plasma

• Red blood cells

• White blood cells

• Platelets

What is coagulation?

Process of blood clotting

What is an anticoagulant?

Substance that prevents clotting

What is plasma?

• Liquid portion of anticoagulated blood

• Still contains clotting factors like fibrinogen

• Makes up 55% of total blood volume

• Contains proteins, clotting factors, enzymes, electrolytes, glucose, fats, hormones, cholesterol

What is serum?

• Liquid portion of coagulated blood

• Not contain clotting factors

When a blood sample clots, what does it yield?

Serum

When a blood sample doesn’t clot due to an anticoagulant, what does it yield?

Plasma

What is the buffy coat?

A thin layer of white blood cells and platelets that separates the red blood cells from plasma

What is the normal blood pH range?

7.35 to 7.45

What is acidosis?

When a patient has blood that’s too acidic; below normal range

What is alkalosis?

When a patient has blood that’s too alkaline; above normal range

What are erythrocytes?

• Red blood cells

• Contain hemoglobin- oxygen carrying protein

• Transports oxygen throughout the body and removes carbon dioxide

What is anemia?

Too few RBCs; low level of RBCs

What is polycythemia vera?

Too many RBCs; excessive amount of RBCs

What is hemochromatosis?

A disorder where the body absorbs too much iron which can lead to abnormal RBCs and excess iron can accumulate in major organs

What are leukocytes?

• White blood cells

• Protect the body from infection and play an important role in immunity

What is leukopenia?

Too few WBCs; can result from a viral infection or as a side effect of chemotherapy

What is leukocytosis?

Too many WBCs; usually indicates that body is fighting an infection

What is homeostasis?

The body’s ability to maintain a stable and balanced internal environment

What are thrombocytes?

• Platelets

• Aid in blood coagulation and are critical for wound healing and repairing damaged blood vessels

What is the antecubital (AC) fossa?

A triangular shaped area in the inner arm at the crease of the elbow; area most commonly used for blood collection

What are the 3 prominent veins in the arm listed in order of preference?

1. Median cubital vein

2. Cephalic vein

3. Basilic vein

What is the median cubital vein?

The first choice/most common choice for venipuncture because it is securely anchored in the surrounding tissue and less likely to move

What is the cephalic vein?

It is located on the thumb side of the AC fossa

• Often easier to palpate in obese patients

What is the basilic vein?

Least securely anchored vein and is located close to the brachial artery

• Risk of puncturing the artery

If veins can’t be located in the AC fossa in either arm, what is the next best option?

The hand

What is an antigen?

A substance that triggers an immune response leading to the production of antibodies, which are protein substances that help defend the body

What antigens are present in the major 4 blood groups?

• Group A: only A antigen present

• Group B: only B antigen present

• Group AB: both A and B antigens present

• Group O: no antigen present

How is blood classified as positive?

If the Rhesus (Rh) protein is present on the surface of RBCs

What blood type is the universal donor

O negative

What blood type is the universal recipient?

AB positive

What is agglutination

Clumping of RBCs that can lead to cells rupturing and releasing a toxic amount of hemoglobin into bloodstream

How much blood is typically collected during a blood donation?

450-500 mL; about one pint

For adults, what is the recommended range of total blood volume allowed to be withdrawn within a 24 hr period?

1% to 5%

What are the minimum requirements for donating blood?

• Be at least 18 yrs old

• Be under the age of 67

• Weigh at least 110 pounds

• Have a hemoglobin (Hgb) level of at least 12.5 g/dL

• Have a hematocrit (Hct) level of at least 38%

What is the largest organ in the body?

The skin which is part of the integumentary system

What are the 3 layers of the skin?

• Epidermis: Outermost layer of skin and doesn’t have an active blood supply, composed of epithelial cells, where melanin is produced

• Dermis: Middle layer of skin that contains nerves, lymph nodes, and blood vessels

• Subcutaneous: Innermost layer beneath the skin that consists of adipose tissue which provides insulation, cushioning, and energy storagne

What is the central nervous system (CNS)?

Includes the brain, spinal cord, and cerebrospinal fluid (CSF)

What is the peripheral nervous system (PNS)?

Includes the nerves that connect the CNS to the rest of the body

What are the 3 types of muscle?

• Cardiac: found in the heart; striated/striped; responsible for pumping blood

• Skeletal: voluntary muscles attached to bones that allow movement

• Smooth: involuntary muscles that function automatically

What does the urinary system consist of?

• Bladder

• Urethra

• Two ureters

• Two kidneys

What is the primary function of the urinary system?

To filter, store, and eliminate waste products (urine) from the body

What is scope of practice?

The procedures and responsibilities a healthcare professional is legally and ethically allowed to perform

What are phlebs not allowed to do?

Provide, interpret, or explain results