Patho Exam #2

Question 1

Lymph nodes

Answer 1

 Part of the immune and hematologic systems
o Facilitates maturation of lymphocytes
o Transports lymphatic fluid back to the circulation
o Cleanses the lymphatic fluid of MOs and foreign particles

Question 2

Evaluation of the Hematologic System

Answer 2

•	Tests of bone marrow function
	Bone marrow aspiration
	Bone marrow biopsy
	Measurement of bone marrow iron stores
	Differential cell count
•	Blood tests
	Large variety of tests – CBC

Question 3

Aging and the Hematologic System

Answer 3

• Erythrocyte lifespan is normal, but are replaced more slowly
 Possible causes
o Iron depletion
o Decreased total serum iron, iron-binding capacity, and intestinal iron absorption
 Lymphocyte function decreases with age
 Humoral immune system is less responsive

Question 4

Quantitative disorders

Answer 4

 Increases/decreases in cell numbers
o Leukopenia
 Not normal and not beneficial
 Low WBC predisposes a patient to infection
o Leukocytosis
 Normal protective physiologic response to physiologic stressors
 Bone marrow disorders or premature destruction of cells
 Response to infectious MO invasion

Question 5

Qualitative disorders

Answer 5

 Disruption of cellular function

Question 6

Neutropenia

Answer 6

• Reduction in circulating neutrophils
• Causes
 Prolonged severe infection
 Decreased production caused by chemotherapy
 Reduced survival
 Abnormal neutrophil distribution and sequestration

Question 7

Leukemias

Answer 7

• Malignant disorder of the blood and blood-forming organs (Hematopoietic stem cells)
• Excessive accumulation of leukemic cells
 In bone marrow mutation
 Excessive accumulation of lymphocytic – B, T, or NK cells
 Excessive accumulation of myelogenous – monocytes or granular leukocytes

Question 8

Acute leukemia

Answer 8

 Presence of undifferentiated or mature cells, usually blast (leukoblast) cells

Question 9

Chronic leukemia

Answer 9

 Predominant cell is mature but does not function normally

Question 10

Leukemia Symptoms

Answer 10

• Related to suppressed bone marrow function
 Infection – severe and/or recurrent
 Night sweats, fever, lymphadenopathy
 Anemia, pallor, fatigue, weight loss
 Nose bleeds, bleeding gums, petechiae (small red or purple spot caused by bleeding into the skin), ecchymosis (bruise)
• Related to infiltration to other organs with immature cells
 Enlarged spleen, liver, lymph nodes, bone and joint pain
 CNS symptoms (ALL & AML): headache, nausea, vomiting

Question 11

Leukemia Diagnosis

Answer 11

• Abnormalities in Complete blood cell count (CBC)
• X rays
• Bone marrow aspiration reveals leukemic blast cells and tumor markers
 Syringe is used to suck marrow from the iliac crest or the sternum
 Procedure used to examine bone marrow cells
• Lumbar puncture

Question 12

Chemotherapy

Answer 12

 Needs to be systemic
 Goal is to rid body of leukemic cells without completely destroying bone marrow
 Bone marrow transplant provides cure for some types of leukemia

Question 13

Acute Lymphocytic Leukemia (ALL) & Acute Malloid Leukemia (AML)

Answer 13

 Induction Therapy
o Intense combo of chemotherapy and radiation
o Given at time of diagnosis
o Goal to achieve remission
 Consolidation Therapy
o Given once remission achieved
o Variation of chemotherapy given during induction
o Curative intent; may be one treatment or repeated cycles for 1 – 2 years
o CNS treatment in children
 Maintenance Therapy
o Purpose to maintain remission
o Decreased dose of chemotherapy
o Usually given in cycles over several years (2-5)

Question 14

Chronic Malloid Leukemia (CML)

Answer 14

 Chemo agents – administered orally
 In blast crisis
o Drugs similar to those used in AML
 Leukapheresis (WBCs are separated from a sample of blood), plateletpheresis (platelets are separated from a sample of blood)
 Bone marrow transplant before blast crisis

Question 15

Chronic Lymphocytic Leukemia (CLL)

Answer 15

 Goal – palliation (make a disease or its symptoms less severe or unpleasant without removing the cause)
 Oral chemo agents to control WBC count

Question 16

Malignant Lymphomas

Answer 16

• Uncontrolled proliferation of lymphocytes arising from lymphoid tissues
• Invade bone marrow and other organs
Hodgkin’s Lymphoma
Non-Hodgkin’s Lymphoma

Question 17

Hodgkin’s Lymphoma (Disease)

Answer 17

 Associated with Epstein-Barr Disease (EBV)
 Form of lymphoma demonstrating the Reed-Sternberg cell, seen after doing a biopsy on a patient’s lymph node]
 Bimodal incidence peak
o Teens to mid-twenties or after 50
 Thought to be associated with inflammatory reaction to infectious agent, virus – EBV
 Painless progression of single node or group of nodes; spreads in continuous pattern
 Usually good prognosis

Question 18

Non-Hodgkin’s Lymphoma:

Answer 18

 Linked with chromosomal translocation
 Worst type
 Heterogeneic group of neoplastic disorders of lymphoid tissue; absence of Reed-Sternberg cell
 More prevalent than Hodgkin’s Lymphoma
o More common in older adults
o Common among persons who are immunosuppressed
 Viruses also implicated as possible cause
 Multi-centric in origin, non-continuous spread to lymph nodes and early to liver, spleen, and bone marrow
 Poorer prognosis

Question 19

Malignant Lymphomas Symptoms

Answer 19

 Painless, enlarged lymph nodes
 Low grade fever, night sweats, weight loss, fatigue
 Enlarged liver, spleen

Question 20

Malignant Lymphomas Diagnosis

Answer 20

 Biopsy lymph node
 CT scan
 Bone marrow aspiration

Question 21

Malignant Lymphoma: Treatment

Answer 21

• Hodgkin’s Lymphoma
 If localized, radiation therapy alone (Stage I & II)
 Stage IIIA: radiation therapy and combination chemotherapy
 Stage IIIB & IV: combination chemotherapy
• Usually combination of radiation therapy and chemotherapy as multicentric (multiple centers of origin) in nature

Question 22

Multiple Myeloma

Answer 22

• Malignant disease of plasma cells – abnormal B cells
• Malignant plasma cells produce
 Immune deficiency
 Increased amount of nonfunctional immunoglobulin
o Called the M protein – increases blood viscocity
 Substance that stimulates and enhances angiogenesis
• Malignant plasma cells can infiltrate other tissues

Question 23

Multiple Myeloma Symptoms

Answer 23

 Bone pain
 Osteoclastic activity increased
o Osteolytic lesions and evidence of osteoporosis on X-ray
o Pathologic fractures
 Hypercalcemia, anemia, leukopenia, thrombocytopenia
 Renal failure (damage due to Bence Jones protein)

Question 24

Multiple Myeloma Diagnosis

Answer 24

 Serum protein electrophoresis
o Elevated monoclonal protein spike
 Bone marrow aspiration
o Sheets of plasma cells present

Question 25

Multiple Myeloma Treatment

Answer 25

 Chemotherapy: control illness o Various cheme agents + corticosteroids (Decadron)  Thalidomide (Thalomid) to prevent angiogenesis (used to be used to treat, but caused deformed limbs if mother took in early pregnancy)  Biologic agents – alpha-interferon to maintain remission  Radiation for bone lesions  Bisphosphonates to diminish osteoclastic activity  Promote renal function  Symptom management o Pain, hypercalcemia, increased blood viscosity o Prevent, treat infections

Question 26

Anemia

Answer 26

``` • Reduction in total number of erythrocytes in circulating blood or in the quality or quantity of hemoglobin  Impaired erythrocyte production  Acute or chronic blood loss  Increased erythrocyte destruction  Combination of the above ```

Question 27

Anemia Morphology

Answer 27

```  Morphology o Based on MCV, MCH, and MCHC values o Size  Identified by terms that end in “-cytic”  Macrocytic, microcytic, normocytic o Hemoglobin content  Identified by terms that end in “-chromic”  Normochromic and hypochromic ```

Question 28

Anemia Physiology Manifestation

Answer 28

o Reduced oxygen-carrying capacity o Heme iron: organ meats good source o Non-heme irons: Vitamin C helps observe

Question 29

Classic Anemia Symptoms

Answer 29

Fatigue, dypsnea, weakness, and pallor

Question 30

Microcytic-Hypochromic Anemia

Answer 30

• Iron deficiency anemia  Most common type of amemia worldwide  Nutritional iron deficiency  Metabolic or functional deficiency  Characterized by RBCs that are abnormally small and contain reduced amounts of hemoglobin  Related to: o Disorders of iron metabolism o Alcoholism o Progression of iron deficiency causes:  Brittle, thin, coarsely ridged, and spoon-shaped nails  A red, sore, and painful tongue

Question 31

Macrocytic-Normochromic Anemia

Answer 31

• Folate deficiency anemia  Absorption of folate occurs in the upper small intestine  Not dependent on any other factor  Neurologic manifestations generally not seen  Treatment requires daily oral administration of folate

Question 32

Normocytic-Normochromic Anemia

Answer 32

``` • Hemolytic anemia  Accelerated destruction of RBCs  Autoimmune hemolytic anemias  Immunohemolytic anemia: blood transfusion reaction  Drug-induced hemolytic anemia ```

Question 33

Pernicious Anemia

Answer 33

• Lack in intrinsic factor, no B12 absorption • Signs and symptoms  Nerve demyelination  Atrophic glossitis (redness and swelling of tongue, beefy red) • People at risk usually obese due to surgeries

Question 34

Mononucleosis

Answer 34

Infection of B lymphocytes • Epstein Barr virus • Most infectious two weeks before symptoms start to show • Ruptured spleen can be caused by this which can cause death • Diagnosed by monospot test

Question 35

Burkitt-lymphoma

Answer 35

* B-cell, Epstein Barr * Most common types of non-Lodgkins lymphoma in children * Found in jaw and facial muscles

Question 36

Gas transport

Answer 36

 Ventilation of the lungs  Diffusion of oxygen from the alveoli into the capillary blood  Perfusion of systemic capillaries with oxygenated blood  Diffusion of oxygen into systemic capillaries into the cells  Diffusion of CO2 occurs in reverse order

Question 37

Factors Affecting Alveolar-Capillary Gas Exchange

Answer 37

* Surface area available for diffusion * Thickness of the alveolar-capillary membrane * Partial pressure of alveolar gases * Solubility and molecular weight of the gas

Question 38

Lung compliance

Answer 38

* C=△V/△P | * △V Lung volume can be accomplished with given △P respiratory pressure

Question 39

Airway resistance

Answer 39

* Volume of air that moves into and out of the air exchange portion of the lungs * Directly related to the pressure difference between the lungs and the atmosphere * Inversely related to resistance the air encounters as it moves through the airways

Question 40

Cheyne-Stokes Respirations

Answer 40

o Characterized by oscillation of ventilation between apnea and hyperpnea o Compensate for changing serum partial pressures

Question 41

Kussmaul Respirations

Answer 41

o Deep and labored breathing pattern often associated with severe metabolic acidosis, particularly diabetic ketoacidosis (DKA), but also renal failure o Form of hypertentilation (reduces CO2 in blood due to increased rate or depth of respiration)

Question 42

Signs and Symptoms of Pulmonary Disease

Answer 42

• Dyspnea: not breathing properly  Subjective sensation of uncomfortable breathing • Orthopnea: difficulty breathing when laying down • Paroxysmal nocturnal dyspnea (PND): sleeping and then wake up sharply, can be associated with cardiac

Question 43

Mechanisms Involved in Dyspnea

Answer 43

• Stimulation of lung receptors • Increased sensitivity to changes in ventilation perceived through CNS mechanisms • Reduced ventilatory capacity or breathing reserve • Stimulation of neural receptors in the muscle fibers of the intercostals and diaphragm and of receptors in the skeletal joints • Associated conditions  Primary lung disease  Heart disease  Neuromuscular disorders

Question 44

Signs and Symptoms of Pulmonary Disease

Answer 44

``` • Hypoventilation  Hypercapnia • Hyperventilation  Hypocapnia • Cough  Acute cough  Chronic cough • Hemoptysis: coughing up blood • Cyanosis • Pain: chest pain • Clubbing: finger nails, pulmonary obstructive disorders • Abnormal sputum: look for color (green, yellow, pink, brown), consistency, thickness, copious amounts of sputum, smell • Pulmonary edema: fluid in or around lungs, congestive heart failure (CHF) ```

Question 45

Hypoxemia

Answer 45

• Shortness of breath, increased respiration, changing mental status (esp in elderly), pale or cyanosis • Results from:  Inadequate O2 in air  Disease of respiratory system  Dysfunction of the neurological system  Alterations in circulatory function • Mechanisms  Hypoventilation  Impaired diffusion of gases  Inadequate circulation of blood through the pulmonary capillaries  Mismatching of ventilation and perfusion

Question 46

Mild Hypoxemia

Answer 46

```  Metabolic acidosis  Increase in heart rate  Peripheral vasoconstriction  Diaphoresis  Increase in blood pressure  Slight impairment of mental performance ```

Question 47

Chronic Hypoxemia

Answer 47

```  May be insidious in onset and attributed to other causes o Compensation masks condition  Increased ventilation  Pulmonary vasoconstriction  Increased production of RBCs  Cyanosis ```

Question 48

Hypercapnia

Answer 48

• Increased arterial PCO2 • Caused by hyperventilation or mismatching or ventilation and perfusion • Effects  Acid-base balance (decreased pH, respiratory acidosis)  Kidney function  NS function  Cardiovascular function

Question 49

Pleural effusion

Answer 49

Abnormal collection of fluid in pleural cavity  Transudate or exudate, purulent (containing pus), chyle (fluid that consists of fat droplets and lymph), or sanguineous (bloody)

Question 50

Spontaneous Pneumothorax

Answer 50

 Occurs when air-filled blister on the lung surface ruptures

Question 51

Traumatic Pneumothorax

Answer 51

 Caused by penetrating or non-penetrating injuries |  Can be from car accident, incident is involved

Question 52

Tension Pneumothorax

Answer 52

 Occurs when the intrapleural pressure exceeds atmospheric pressure  Build-up of air within pleural space, usually due to a laceration which allows air to escape in pleural space but doesn’t return

Question 53

Characteristics and Symptoms of Pleural Pain

Answer 53

* Abrupt in onset * Unilateral, localized to lower and lateral part of the chest * May be referred to the shoulder * Usually made worse by chest movements * Tidal volumes are kept small * Breathing becomes more rapid * Reflex splinting of the chest may occur

Question 54

Diagnosis of Pleural Effusion

Answer 54

 Chest radiographs, chest ultrasound |  Computed tomography (CT)

Question 55

Treatment of Pleural Effusion

Answer 55

* Thoracentesis: inserting needle in lungs to draw out fluid * Injection of sclerosing agent (develops scar tissue) into the pleural cavity * Open surgical drainage (chest tube, usually used to inflate lungs that collapse)

Question 56

Actelectasis

Answer 56

Incomplete expansion of a lung or portion of a lung

Question 57

Causes of Actelectasis

Answer 57

 Airway obstruction  Lung compression such as occurs in pneumothorax or pleural effusion  Increased recoil of lung due to loss of pulmonary surfactant

Question 58

Causes of Respiratory Failure

Answer 58

``` • Impaired ventilation  Upper airway obstruction  Weakness of paralysis of respiratory muscles  Chest wall injury • Impaired matching of ventilation and perfusion • Impaired diffusion  Pulmonary edema  Respiratory distress syndrome ```

Question 59

Treatment of Respiratory Function

Answer 59

* Respiratory supportive care directed toward maintenance of adequate gas exchange * Establishment of an airway * Use of bronchodilating drugs * Antibiotics for respiratory infections * Ensure adequate oxygenation

Question 60

Acute Respiratory Distress Syndrome (ARDS)

Answer 60

Damaged alveoli, oxygenation severely impaired • Injury to pulmonary capillary endothelium • Inflammation and platelet activation • Surfactant inactivation • Atelectasis

Question 61

Causes of ARDS

Answer 61

* Aspiration in gastric contents * Major trauma (with or without fat emboli) * Sepsis secondary to pulmonary or non-pulmonary infections * Acute pancreatitis * Hematologic disorders * Metabolic events * Reactions to drugs and toxins

Question 62

ARDS Manifestations

Answer 62

```  Hyperventilation  Respiratory alkalosis  Dyspnea and hypoxemia  Metabolic acidosis  Hypoventilation  Respiratory acidosis  Further hypoxemia  Hypotension, decreased cardiac output, death ```

Question 63

ARDS Evaluation and Treatment

Answer 63

* 100% oxygen * Keep O2 levels above 90% * Physical examination, blood gases, and radiologic examination * Supportive therapy with oxygenation and ventilation and prevention of infection * Surfactant to improve compliance

Question 64

Chronic obstructive airway disease (COPD)

Answer 64

• Expiration is affected • Progression can be slowed with treatment • Inflammation and fibrosis of bronchial wall • Hypertrophy of submucosal glands • Hypersecretion of mucus (asthmatic patients, chronic bronchitis patients) • Loss of elastic lung fibers  Impairs the expiratory flow rate, increases air trapping, and predisposes to airway collapse • Alveolar tissue  Decreases the surface area for gas exchange

Question 65

Causes of COPD

Answer 65

* Chronic bronchitis * Emphysema * Bronchiectasis * Cystic fibrosis

Question 66

Types of COPD

Answer 66

• Emphysema  Enlargement of air spaces (beyond terminal bronchioles, loss of recoil, harder and not as quick) and destruction of lung tissue • Chronic obstructive bronchitis  Obstruction of small airways

Question 67

Pulmonary Emphysema

Answer 67

* Smoking history * Age of onset: 40-50 years * Often dramatic barrel chest (1:1 ratio) * Weight loss * Decreased breath sounds * Normal blood gases until late in disease process * Slowly debilitating disease

Question 68

Chronic Bronchitis

Answer 68

* Smoking history * Age of onset 30-40 years * Barrel chest may be present * Shortness of breath predominant early symptom * Rhonchi often present * Sputum frequent early manifestation * Often dramatic cyanosis * Hypercapnia and hypoxemia may be present * Frequent cor pulmonale and polycythemia * Numerous life threatening episodes due to acute exacerbations

Question 69

Pulmonary Embolism

Answer 69

• Development  Blood-borne substance lodges in a branch of the pulmonary artery and obstructs the flow  Thrombus: arising from DVT  Fat: mobilized from the bone marrow after a fracture or from a tramatized fat depot  Amniotic fluid: enters the maternal circulation after rupture of the membranes at the time of delivery

Question 70

Asthma

Answer 70

```  Environmental o Construction (concrete dust) o Smoking o Pet hair  Preventable o Control whatever triggers asthma attack  Exercise induced  Allergen induced  Stress Induced ```

Question 71

Asthma Symptoms

Answer 71

Wheezing, coughing throughout the night, difficulty breathing, and excess sputum

Question 72

Pneumonia

Answer 72

```  6th leading cause of death  Nosocomial Infection  Spread of respiratory droplets  Hospital/environmental acquired  Can be caused by bacteria (strep)  Haemophilis influenza most common cause ```

Question 73

Tuberculosis

Answer 73

```  Caused by mycobacteria (rod-shaped)  Acid-fast bacillus  Airborne  Patients in negative air-pressure rooms  Droplet precautions  Causeous necrosis (cheesy-looking granules)  TB skin tests o Pos. needs further testing o Chest x-ray o 3 sputum cultures ```

Question 74

Hyperthyroidism

Answer 74

 Thyrotoxicosis: caused by too much thyroid hormone in body, most common type of hyperthyroidism o Exopathalmos: bulging of eyes o Too much T3 and T4 in body o Cured with iodine  Graves disease o Pretibial myxedema o Most common type of hyperthyroidism  Hyperthyroidism resulting from nodular thyroid disease o Goiter: result of iodine deficiency  Thyrotoxic crisis: immediate care needed, most extreme form of hyperthyroidism

Question 75

Hypothyroidism

Answer 75

``` • Primary hypothyroidism  Subacute thyroiditis  Autoimmune thyroiditis (Hashimoto disease)  Painless thyroiditis  Postpartum thyroiditis  Myxedema coma: life threatening • Congenital hypothyroidism • Thyroid carcinoma • Overweight, fatigue, thyroid gland can atrophy, constipation, sensitivity to cold, dry skin and nails, constant pain • Creatinism  44 in or less  Scamp or no hair  Umbilical hernia  Underdeveloped breasts ```

Question 76

Type 1 Diabetes Mellitus

Answer 76

* Demonstrates pancreatic atrophy and specific loss of beta cells * Macrophages, T- and B-lymphocytes, and natural killer cells are present

Question 77

Type 1 Diabetesx Mellitus

Answer 77

* T cells attack and destroy islet cells in pancreas * Body can make insulin but body can’t use it * Obesity * Hypertension * Poor wound healings * Peripheral neuropathy * Amputations * Frequent infections * Liver and kidney disease * End-stage renal disease * retinopathy

Question 78

Type 1 DM

Answer 78

• Genetic susceptibility  Glycogen • Environmental factors • Immunologically mediated destruction of beta cells by T cells • Manifestations  Hyperglycemia, polydipsia, polyuria, polyphagia, weight loss, and fatigue  Have to have insulin

Question 79

Type 2 DM

Answer 79

 Insulin resistance • Body makes insulin, but doesn’t produce enough for glucose in body • Usually seen in 35 years + • Normal should be 70-100 • Orange juice given to help instantly (monosaccharide) • Milk if no OJ present (dissacharide) • Glucose given under gum or by IV

Question 80

Acute Complications of DM

Answer 80

* Hypoglycemia * Diabetic ketoacidosis * Hyperosmolar hyperglycemic nonketotic syndrome (HHNKS) * Somogyi effect * Dawn phenomenon

Question 81

Diabetic ketoacidosis

Answer 81

 Sweet smelling pee  Fat begins to be broken down  Carbs aren’t broken down, glucose not used for energy  Ketones enter bloodstream

Question 82

Hyperosmolar hyperglycemic nonketotic syndrome (HHNKS)

Answer 82

 Life threatening  Enough insulin produced to not get NKA  Not enough insulin produced to not prevent hyperglycemia  High blood sugarm but body still making enough insulin  Ketones aren’t spilled into blood

Question 83

Somogyi effect

Answer 83

Blood glucose drops in sleep, Hormones increase blood sugar too much

Question 84

Dawn phenomenon

Answer 84

Higher blood sugar than anticipated when waking up

Question 85

Chronic Complications of DM

Answer 85

``` • Hyperglycemia and nonenzymatic glycosylation • Hyperglycemia and the polyol pathway  Protein kinase C • Microvascular disease  Retinopathy  Diabetic nephropathy • Macrovascular disease  Coronary artery disease  Stroke  Peripheral arterial disease • Diabetic neuropathies • Infection ```

Question 86

Disseminated Intravascular Coagulation (DIC)

Answer 86

• Complex, acquired disorder in which clotting and hemorrhage simultaneously occur • Result of increased protease activity in the blood caused by unregulated release of thrombin with subsequent fibrin formation and accelerated fibrinolysis • Endothelial damage is the primary initiator of DIC • By activating fibrinolytic system (plasmin), patient’s fibrin degradation product (FDP) and D-dimer levels will increase • Because of the patient’s clinical state, the disorder has a high mortality rate • Treatment is to remove the stimulus and maintain hemodynamic status • Clinical signs and symptoms demonstrate wide variability  Bleeding from venipuncture sites  Bleeding from arterial lines  Purpura, petechiae, and hemotomas  Symmetric cyanosis of the fingers and toes

Question 87

Vitamin K deficiency | Alteration of Coagulation

Answer 87

Necessary for synthesis and regulation of prothrombin, the prothrombin factors (II, VII, XI, X) and proteins C and S (anticoagulants)

Question 88

Liver disease

Answer 88

 Causes a broad range of hemostasis disorders | o Defects in coagulation, fibrinolysis, and platelet number and function

Question 89

Thrombocytopenia

Answer 89

Platelet count <150,000/mm3

Question 90

Hemorrhage from minor trauma

Answer 90

<50,000/mm3

Question 91

Spontaneous bleeding

Answer 91

<15,000/mm3

Question 92

Severe bleeding

Answer 92

<10,000/mm3

Question 93

Sickle Cell Anemia

Answer 93

Mutation in beta chains of HbG | When HbG deoxygenated, beta chains link together forming long protein rods that make the cell sickle

Question 94

Problems caused by Sickle Cell

Answer 94

Blocked capillaries, causing acute pain, infarctions cause chronic damage to liver, spleen, heart, kidneys, eyes and bones Pulmonary infarction > acute chest syndrome Cerebral infarction > stroke Sickled cells more likely to be destroyed

Question 95

Ventilation

Answer 95

the movement of air between the atmosphere and the respiratory portion of the lungs

Question 96

Inspiration

Answer 96

air is drawn into the lungs as the respiratory muscles expand the chest cavity

Question 97

Expiration

Answer 97

air moves out of the lungs as the chest muscles expand the chest cavity becomes smaller

Question 98

Perfusion

Answer 98

the flow of blood through the lungs

Question 99

Diffusion

Answer 99

transfer of gases between air-filled spaces in the lungs and the blood