Chapters 25–27 Review: Respiratory, Digestive & Urinary Systems

These question-and-answer flashcards cover key concepts, structures, and functions from the Respiratory, Digestive, and Urinary system lecture notes in Chapters 25–27, including anatomy, physiology, and common clinical conditions.

What are the two major portions of the respiratory system?

Conducting portion (bulk of system) and respiratory portion (small portion).

Which structures belong to the upper respiratory tract?

Nose, nasal cavity, paranasal sinuses, and pharynx.

Which structures belong to the lower respiratory tract?

Larynx, trachea, bronchi, bronchioles, and alveoli.

List four primary functions of the respiratory system.

Gas exchange, gas conditioning, sound production, olfaction, and defense (any four of these).

Differentiate external and internal respiration.

External respiration is gas exchange between alveoli and capillaries; internal respiration is between capillaries and body tissues.

Give two functions of the nasal cavity.

Olfaction; warming, moistening, filtering, and transporting air to the pharynx.

Name two functions of the paranasal sinuses.

Lighten the skull and provide resonance for sound.

What are the three regions of the pharynx?

Nasopharynx, oropharynx, and laryngopharynx.

State two functions of the pharynx.

Transport air to the larynx and aid in swallowing food to the esophagus.

List two primary functions of the larynx.

Transport air to the trachea and produce sound.

What is the role of the epiglottis?

Channels food and drink toward the esophagus, preventing entry into the airway.

How are pitch and loudness controlled in the vocal folds?

Pitch depends on tension of folds; loudness depends on the amount of air passing through.

Describe two functions of the trachea.

Transports air to the bronchi and traps particulates in mucus.

What tissue lines the trachea?

Pseudostratified ciliated columnar epithelium with goblet cells.

What is the main function of the bronchial tree?

Transport air deep into the lungs and trap particulates.

How do bronchioles differ from bronchi?

Bronchioles lack cartilage rings, have simpler epithelium, and possess smooth muscle.

Which bronchiole marks the last part of the conducting portion?

Terminal bronchiole.

Which bronchiole begins the respiratory portion?

Respiratory bronchiole.

Name the three cell types found in alveoli.

Alveolar type I cells, alveolar type II cells (produce surfactant), and alveolar macrophages.

What is the function of surfactant?

Reduces surface tension, preventing alveolar collapse.

List the three layers of the respiratory membrane.

Alveolar epithelium, fused basement membranes, and capillary endothelium.

State two functions of pleural fluid.

Lubrication and reduction of friction between pleural membranes.

How many lobes does the right lung have?

Three: superior, middle, and inferior lobes.

What anatomical feature accommodates the heart on the left lung?

The cardiac notch.

Which muscle is primary for inhalation?

The diaphragm (contracts during inhalation).

Name two brainstem centers involved in breathing.

Dorsal respiratory group (DRG) and ventral respiratory group (VRG) in the medulla.

Which receptors detect high CO₂, high H⁺, and low O₂?

Peripheral chemoreceptors (carotid and aortic bodies).

What disease produces thick mucus that blocks respiratory passageways?

Cystic fibrosis.

Explain the primary problem in emphysema.

Alveoli are enlarged and nonfunctional, reducing surface area for gas exchange.

Which cancer originates from pseudostratified ciliated columnar epithelium of bronchi?

Squamous cell carcinoma of the lung.

List the six major functions of the digestive system.

Ingestion, digestion, propulsion, secretion, absorption, and defecation.

Differentiate peristalsis and segmentation.

Peristalsis is wave-like propulsion; segmentation is back-and-forth mixing.

What is the peritoneum?

A serous membrane that surrounds many abdominal organs.

Give two functions of the peritoneum.

Reduces friction via lubrication and anchors organs to each other/abdominal wall.

Define retroperitoneal organ and give one example.

Organ that does not project into peritoneal cavity; example: kidney or pancreas.

What are the four tunics of the GI tract from lumen outward?

Mucosa, submucosa, muscularis, and serosa (or adventitia).

Which gland secretes salivary amylase?

Parotid salivary gland (also others, but parotid is primary).

List two enzymes found in saliva.

Salivary amylase and lingual lipase.

Name the three layers of muscle in the stomach.

Oblique, circular, and longitudinal layers.

What is chyme?

Bolus mixed with gastric juices in the stomach.

How much volume can the stomach hold?

Up to approximately 1–2 gallons (about 4 L).

Which cells secrete pepsinogen?

Chief cells of the gastric glands.

What is a peptic ulcer?

Erosion of the stomach or duodenal wall, often caused by Helicobacter pylori.

List the three sections of the small intestine in order.

Duodenum, jejunum, and ileum.

Why are circular folds, villi, and microvilli important?

They increase surface area for nutrient absorption.

State two functions of the large intestine.

Absorption of water/electrolytes and expulsion of waste (defecation).

Which muscle forms the voluntary anal sphincter?

External anal sphincter (skeletal muscle).

What condition is characterized by inflamed diverticula in the colon?

(Not in notes) – but polyp may lead to colorectal cancer; accept: diverticulitis if asked.

Name two functions of the liver.

Produces bile; detoxifies drugs and toxins. (Others include stores nutrients, synthesizes plasma proteins, etc.)

What is the hepatic portal triad composed of?

Branch of hepatic portal vein, branch of hepatic artery, and bile ductule.

Define cirrhosis.

Chronic scarring of liver tissue, often due to alcoholism or hepatitis.

What is the main function of the gallbladder?

Stores and concentrates bile.

What are gallstones?

Crystallized cholesterol or bile salts that may block bile ducts.

Name two digestive enzymes produced by the pancreas.

Proteases (e.g., trypsin), lipases, amylases, or nucleases (any two).

Which autoimmune disease destroys small-intestinal villi when gluten is consumed?

Celiac disease.

Which disorder involves inflammation mainly of the ileum?

Crohn disease.

List three overall functions of the urinary system.

Urine formation, urine storage, urine excretion (micturition).

Give three additional regulatory roles of the kidneys.

Regulate blood volume, ion balance/pH, and erythrocyte production (via EPO).

Why is the right kidney lower than the left?

The large liver on the right side displaces it inferiorly.

Trace the flow of urine from nephron to ureter.

Collecting duct → minor calyx → major calyx → renal pelvis → ureter.

What is the functional unit of the kidney?

The nephron.

Name the two types of nephrons.

Cortical nephrons and juxtamedullary nephrons.

List the three processes of urine formation in order.

Glomerular filtration, tubular reabsorption, and tubular secretion.

Where does most tubular reabsorption occur?

Proximal convoluted tubule (PCT).

Which nephron segment is mainly responsible for tubular secretion?

Distal convoluted tubule (DCT).

What hormones act on the DCT and collecting duct to conserve water and Na⁺?

Antidiuretic hormone (ADH) and aldosterone.

What is the juxtaglomerular (JG) apparatus?

Region where DCT contacts afferent arteriole; regulates filtration and blood pressure.

Define renal failure.

Decrease or cessation of glomerular filtration, acute or chronic.

What is dialysis?

Machine-mediated cleansing of blood to compensate for kidney failure.

Name three places kidney stones (renal calculi) commonly lodge.

Renal pelvis, ureter, or urethra (points of narrowing such as pelvic brim).

Which sphincter is voluntary during urination?

External urethral sphincter (skeletal muscle).

Explain peristalsis in the ureters.

Rhythmic smooth-muscle contractions that propel urine toward the bladder.

What tissue forms the bladder wall and allows distension?

Transitional epithelium with underlying smooth muscle (detrusor muscle).