A & P 2- Lecture Exam 3

What causes metabolic acidosis?

A: Alcohol ingestion; Lactic acid buildup; Ketoacidosis (diabetes, starvation); Kidney failure.

Slide quote: What leads to metabolic acidosis?

“Excessive metabolic wastes… lactic acid, shock, ketosis.”

Where is blood filtered to make filtrate?

Blood is filtered in the renal corpuscle, where the glomerulus is located inside the glomerular capsule.

What kind of capillaries are in the glomerulus?

The glomerulus contains fenestrated capillaries, which allow small particles like water and solutes to pass.

What is the function of the glomerular capsule?

It collects filtrate from the glomerulus and directs it into the proximal convoluted tubule.

What materials become filtrate?

Filtrate includes water, ions, glucose, amino acids, urea, and small solutes.

What is NOT filtered out of the blood?

Blood cells, plasma proteins, and large molecules are not filtered out.

What may occur if there is damage to the filtration membrane?

Larger molecules like proteins or blood cells may leak into the filtrate, causing proteinuria or hematuria.

Describe proteinuria and hematuria.

Proteinuria is protein in urine; hematuria is blood in urine, both indicating filtration membrane damage.

What is GFR (Glomerular Filtration Rate)?

GFR is the volume of filtrate produced by the kidneys per minute.

How much filtrate is formed per day?

About 180 liters of filtrate are produced daily.

What happens if GFR is too high?

Filtrate moves too quickly, leading to dehydration and nutrient loss.

What happens if GFR is too low?

Filtrate moves too slowly, causing waste accumulation in the blood.

Describe the juxtaglomerular apparatus (JGA).

A structure where the afferent arteriole meets the distal convoluted tubule, which regulates blood pressure and GFR.

What afferent/efferent arteriole changes increase GFR?

Dilating the afferent arteriole or constricting the efferent arteriole increases GFR.

What afferent/efferent arteriole changes decrease GFR?

Constraining the afferent arteriole or dilating the efferent arteriole decreases GFR.

How does the sympathetic nervous system regulate the kidney under stress?

It constricts the afferent arteriole, decreasing GFR to conserve water.

Define tubular reabsorption.

Movement of materials from the filtrate back into the blood.

Describe the peritubular capillary bed.

A network of capillaries that reabsorbs water and solutes surrounding the renal tubules.

What direction does tubular reabsorption occur?

From the tubular lumen into the blood.

How much of the organic nutrients are reabsorbed?

Nearly 100% of organic nutrients like glucose and amino acids.

Describe glycosuria and proteinuria.

Glycosuria is glucose in urine; proteinuria is protein in urine.

Define tubular secretion.

Movement of materials from the blood into the filtrate.

What is the direction of movement during tubular secretion?

From blood into the tubular lumen.

What materials are secreted and why?

Drugs, toxins, and excess ions are secreted to eliminate waste and maintain pH.

What is produced as the end product of these processes? Where is it excreted?

Urine, excreted through the collecting duct, papilla, calyces, renal pelvis, ureter, bladder, and urethra.

What gland produces ADH and what is its target?

ADH is produced by the hypothalamus and targets the collecting ducts.

What is the main function of ADH and what regulates it?

ADH promotes water reabsorption, regulated by blood osmolarity and hydration.

What gland produces aldosterone and what is its target?

Aldosterone is produced by the adrenal cortex and targets the distal convoluted tubule.

What is the main function of aldosterone and what regulates it?

Aldosterone reabsorbs sodium, regulated by RAAS and potassium levels.

What happens when there is a drop in pressure?

JG cells release renin in response to low blood pressure.

What produces angiotensinogen and what converts it to Angiotensin I?

Angiotensinogen is produced by the liver and converted by renin.

What converts Angiotensin I to Angiotensin II and what organ produces it?

ACE converts Angiotensin I to Angiotensin II, produced in the lungs.

What are three effects of Angiotensin II?

Vasoconstriction, stimulates aldosterone release, and stimulates ADH release.

What are other effects of Angiotensin II?

Increases thirst and sodium reabsorption.

What is the end result of the actions of Angiotensin II on systemic blood pressure?

Increases systemic blood pressure.

Who might take an ACE inhibitor and why?

Individuals with high blood pressure to prevent Angiotensin II formation.

Describe dilute urine. Are ADH or aldosterone present?

Dilute urine is low in solutes and occurs with little or no ADH.

Describe concentrated urine. Are ADH or aldosterone present?

Concentrated urine is rich in solutes, occurs with ADH present.

What are the physical characteristics of urine?

Typical characteristics include yellow color, slightly aromatic odor, pH around 6, and specific gravity of 1.001 to 1.035.

What are the chemical constituents of urine?

Normal urine contains water, urea, and ions; abnormal constituents include glucose, proteins, ketones, blood, bilirubin, and pus.

What causes each abnormal constituent in urine?

Glycosuria (high blood glucose), proteinuria (filtration damage), ketonuria (fat breakdown), hemoglobinuria (hemolysis), bilirubinuria (liver issues), hematuria (bleeding), pyuria (infection).

Define diuretic.

A substance that increases urine output.

What are examples of diuretics?

Caffeine, alcohol, and certain medications.

What is renal clearance?

The rate at which kidneys remove a substance from the blood.

What is renal failure?

The inability of the kidneys to filter blood properly.

What is dialysis?

A procedure that filters blood when kidneys are not functioning.

What is a renal calculi? What causes it?

A kidney stone caused by mineral buildup like calcium or uric acid.

What is micturition?

The process of urination.

What muscles are involved in micturition?

Detrusor muscle contracts; internal and external urethral sphincters relax to allow urination.

What happens at ~200 mL in the bladder?

The urge to void is triggered by stretch receptors.

What happens at ~400 mL in the bladder?

A stronger urge to urinate; harder to ignore.

What happens at 500-600 mL in the bladder?

Voluntary control over urination may be lost.

Describe incontinence and urinary retention.

Incontinence is the inability to control urination; urinary retention is the inability to empty the bladder.

Nose

Provides airway for respiration.

Olfactory mucosa

Located in the superior nasal cavity and contains smell receptors.

Respiratory mucosa

Lines nasal cavity sides and base, trapping particles with mucus.

Sinuses

Frontal, sphenoid, and ethmoid bones that lighten the skull.

Nasopharynx

Region that only allows air to pass.

Oropharynx

Region that allows both food and air to pass.

Laryngopharynx

Region that allows both food and air to pass.

Pharyngeal tonsil

Located in the nasopharynx.

Palatine tonsil

Located at the back of the oral cavity.

Lingual tonsil

Located at the base of the tongue.

Pharyngotympanic tubes

Connect nasopharynx to middle ear to equalize pressure.

Larynx

Routes air to the trachea and food to the esophagus; involved in voice production.

Adam's apple

Thyroid cartilage that forms the structure of the larynx.

Elastic cartilage

Type of cartilage that covers larynx during swallowing.

Hyaline cartilage

Type of cartilage found in thyroid and tracheal cartilages.

Vestibular folds

Protect the airway (false vocal cords).

Vocal folds

Produce sound (true vocal cords).

Laryngitis

Inflammation of vocal cords causing hoarseness.

Valsalva maneuver

Breath-holding while bearing down, increases abdominal pressure.

Trachea

Located in mediastinum, with C-shaped cartilaginous rings.

Goblet cells

Produce mucus that traps debris in the respiratory tract.

Mucociliary elevator

Mechanism for moving debris upward using cilia.

Parietal pleura

Lines the thoracic cavity.

Pulmonary pleura

Covers the lungs (visceral pleura).

Alveoli

Sites of gas exchange with a large surface area.

Respiratory membrane

Very thin membrane for efficient gas diffusion.

Pulmonary arteries

Carry deoxygenated blood to the lungs.

Pulmonary veins

Carry oxygenated blood to the heart.

Bronchioles

Small airways with smooth muscle and no cartilage.

Inspiration

Phase of ventilation where diaphragm contracts and air flows in.

Expiration

Phase of ventilation where air flows out due to pressure increase.

Lung compliance

Ease of lung expansion.

Surfactant

Substance that reduces surface tension in alveoli.

Spirometer

Device used to measure lung volumes and capacities.

External respiration

Gas exchange between alveoli and blood.

Pulmonary edema

Condition that thickens the membrane, reducing gas exchange.

Emphysema

Lung condition that destroys alveoli, reducing surface area.

Hemoglobin

Protein that binds oxygen in red blood cells.

Saturated hemoglobin

Hemoglobin fully loaded with oxygen.

Carbon dioxide transport

Majority transported as bicarbonate in blood.

Medulla

Part of the brain that sets respiratory rhythm.

Perfusion

Movement of oxygen into tissues.

Asthma

Condition marked by inflamed bronchi and increased airway resistance.

Pneumonia

Condition where alveoli are fluid-filled, reducing compliance.

COPD

Chronic obstructive pulmonary disease, includes emphysema and bronchitis.

Lung cancer

Uncontrolled cell growth in lung tissue, primarily linked to smoking.