Respiratory, Digestive, and Urinary Systems Review

A comprehensive set of flashcards covering key concepts from the lecture notes on the respiratory, digestive, and urinary systems, including structure, function, physiology, and common disorders.

What are the two main portions of the respiratory system?

The conducting portion (bulk of the system) and the respiratory portion (site of gas exchange).

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.

Name four general functions of the respiratory system.

Gas exchange, gas conditioning, sound production, olfaction, and defense.

External respiration occurs between which two structures?

Alveoli and pulmonary capillaries.

Internal respiration occurs between which two structures?

Systemic capillaries and body tissues.

List three functions of the nasal cavity.

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

What are the roles of the paranasal sinuses?

Lighten the skull and act as resonance chambers for sound.

What are the three regions of the pharynx?

Nasopharynx, oropharynx, and laryngopharynx.

State two main functions of the pharynx.

Transport air to the larynx and assist in swallowing food.

What are the primary functions of the larynx?

Transport air to the trachea and produce sound.

What is the role of the epiglottis during swallowing?

It channels food and drink into the esophagus, preventing aspiration into the airway.

Which three factors influence voice production?

Range (length/thickness of vocal folds), pitch (tension of folds), and loudness (amount of air).

What type of epithelium lines the trachea?

Pseudostratified ciliated columnar epithelium with goblet cells.

List two functions of the trachea.

Transport air to the primary bronchi and trap particulates in mucus.

Describe two structural changes that occur as bronchi branch into bronchioles.

Incomplete cartilage rings become smaller/fewer and epithelium transitions from pseudostratified columnar to simple columnar or squamous; smooth muscle becomes prominent.

Which bronchiole marks the last part of the conducting portion?

Terminal bronchiole.

Which bronchiole marks the beginning of the respiratory portion?

Respiratory bronchiole.

What cell type produces pulmonary surfactant?

Alveolar Type II cells.

What forms the respiratory membrane?

Alveolar epithelium, fused basement membranes, and capillary endothelium.

Name the two pleural membranes.

Parietal pleura and visceral pleura.

State two functions of pleural fluid.

Lubrication and reduction of friction between lung surfaces during breathing.

How many lobes does the right lung have and what separates them?

Three lobes separated by the horizontal and oblique fissures.

How many lobes does the left lung have and which landmark accommodates the heart?

Two lobes; the cardiac notch accommodates the heart.

Which muscle is the primary driver of inhalation?

The diaphragm.

Which respiratory center controls basic rhythm and is located in the medulla?

The dorsal respiratory group (DRG) and ventral respiratory group (VRG).

What condition results in thick mucus that obstructs respiratory passages?

Cystic fibrosis.

What is pneumonia?

An infection causing fluid and leukocyte accumulation in alveoli, making lung tissue appear opaque on x-ray.

Define emphysema.

A respiratory disease characterized by enlarged, nonfunctional alveoli leading to reduced gas exchange surface area.

What type of epithelium gives rise to most lung cancers such as squamous cell carcinoma?

Pseudostratified ciliated columnar epithelium of the bronchial tree.

List the accessory digestive organs.

Teeth, tongue, salivary glands, liver, gallbladder, and pancreas.

Name the six major functions of the digestive system.

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

Differentiate peristalsis and segmentation.

Peristalsis is wave-like muscle contractions propelling contents; segmentation is localized mixing contractions.

What is the peritoneum?

A serous membrane surrounding many abdominal organs.

Define retroperitoneal organs and give two examples.

Organs that do not project into the peritoneal cavity; examples: kidneys and pancreas.

Which layer of the GI tract contains the myenteric nerve plexus?

The muscularis layer.

Which epithelium lines the esophagus?

Non-keratinized stratified squamous epithelium.

What is Barrett esophagus and why is it clinically important?

Metaplasia of esophageal epithelium due to chronic reflux; increases risk of esophageal cancer.

What volume can the stomach hold when fully distended?

Approximately 1–2 gallons.

Which stomach cells secrete hydrochloric acid?

Parietal cells.

What is chyme?

A semi-fluid mixture of ingested food and gastric juices.

Most peptic ulcers are caused by what bacterium?

Helicobacter pylori.

Name the three sections of the small intestine in order.

Duodenum, jejunum, ileum.

What structural feature increases surface area in the small intestine?

Circular folds (plicae circulares), villi, and microvilli.

List two primary functions of the large intestine.

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

Which muscle forms the internal anal sphincter?

Smooth muscle.

What is a colorectal polyp and why is it significant?

A mucosal growth that can become malignant, leading to colorectal cancer.

Give three key functions of the liver.

Produces bile, detoxifies blood, stores nutrients/vitamins, synthesizes plasma proteins, recycles old RBCs, and regulates cholesterol.

What is cirrhosis and a common cause?

Replacement of liver tissue with scar tissue; often caused by chronic alcoholism or hepatitis.

What do gallstones obstruct and what surgery removes the gallbladder?

They obstruct the cystic/common bile ducts; removal is called cholecystectomy.

Which pancreatic juice components digest proteins?

Proteases.

What autoimmune disorder is triggered by gluten and damages small-intestinal villi?

Celiac disease.

Which inflammatory bowel disease primarily affects the ileum with skip lesions?

Crohn disease.

Which inflammatory condition is limited to the large intestine and raises colon cancer risk?

Ulcerative colitis.

List three major functions of the urinary system.

Formation, storage, and excretion of urine; regulation of blood volume/pressure, ionic balance, pH; erythrocyte production.

Why is the right kidney lower than the left?

Because of the large size and position of the liver.

Name the functional unit of the kidney.

The nephron.

What structures comprise the renal corpuscle?

Glomerulus and glomerular (Bowman) capsule.

List the three processes performed by a nephron.

Glomerular filtration, tubular reabsorption, and tubular secretion.

Which nephron type has long loops extending deep into the medulla and helps concentrate urine?

Juxtamedullary nephrons.

What percentage of water is normally reabsorbed in the proximal convoluted tubule?

Approximately 65%.

Which hormones increase water reabsorption in the distal convoluted tubule and collecting duct?

Antidiuretic hormone (ADH) and aldosterone.

Define glomerular filtration.

Movement of plasma and small solutes from glomerular blood into the capsular space.

What is the juxtaglomerular apparatus responsible for?

Regulating blood pressure and filtration rate via renin release.

Where does tubular secretion mainly occur and what is secreted?

In the distal convoluted tubule; mainly ions such as K+ and H+, and toxins/drugs.

Which vessels supply and drain individual glomeruli?

Afferent arterioles supply; efferent arterioles drain.

Explain renal failure.

A decrease or cessation of glomerular filtration, leading to accumulation of waste products in blood.

What therapy can temporarily replace kidney filtration?

Dialysis.

Urine passes from collecting ducts to the exterior in what order?

Collecting duct → minor calyx → major calyx → renal pelvis → ureter → urinary bladder → urethra.

How is urine propelled down the ureters?

By peristaltic contractions of smooth muscle.

Name the two urethral sphincters and their muscle types.

Internal urethral sphincter (smooth muscle) and external urethral sphincter (skeletal muscle).

What are renal calculi?

Kidney stones—crystalline structures that may obstruct urinary tract flow.

Which respiratory disease is characterized by reversible bronchoconstriction and excess mucus?

Asthma.

What structural lung change is commonly seen in chronic smokers?

Black deposits and enlarged, fewer alveoli indicative of emphysema.

Name three enzymes found in saliva and their substrates.

Salivary amylase (starches), lingual lipase (lipids), and lysozyme (bacterial cell walls).

What is the role of bile produced by the liver?

Emulsification of fats in the small intestine.

Which pancreatic enzyme class digests nucleic acids?

Nucleases.

What is the purpose of intestinal goblet cells?

Secrete mucus to lubricate and protect intestinal lining.

Which vitamins are produced by bacteria in the large intestine?

Some B vitamins and vitamin K.

What does the Bristol Stool Chart assess?

Consistency and form of human feces to gauge GI health.

Differentiate diarrhea and constipation.

Diarrhea: inadequate water absorption; constipation: difficulty or inability to defecate.

Which nerve carries parasympathetic fibers to most of the GI tract up to the transverse colon?

The vagus nerve (CN X).

What is a tracheotomy and when is it performed?

Surgical creation of an opening in the trachea to bypass upper airway obstruction or aid ventilation.

Which respiratory center modifies breaths based on sensory information like irritant receptors?

The pontine respiratory center.

Name two types of chemoreceptors that influence respiration and what they detect.

Central chemoreceptors (detect increased CO2/H+ in CSF) and peripheral chemoreceptors (detect increased CO2/H+, decreased O2 in blood).

What structures form a portal triad in the liver?

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

Which ligament attaches the liver to the anterior abdominal wall?

The falciform ligament.

Where is the ileocecal valve located and what is its role?

Between ileum and cecum; regulates entry of chyme into the large intestine.

Define micturition.

The process of expelling urine from the urinary bladder (urination).

Which hormone stimulates red blood cell production released by the kidneys?

Erythropoietin (EPO).