questions 70-105 from study guide

Brain Control of Ventilation

• Ventilation is controlled by the medulla oblongata.

Intrapulmonary Pressure During Inspiration

• Intrapulmonary pressure decreases below atmospheric pressure during inspiration.

Role of Negative Intrapleural Pressure

• Negative intrapleural pressure prevents lung collapse.

Intrapulmonary and Atmospheric Pressure During Expiration

• During expiration, intrapulmonary pressure becomes greater than atmospheric pressure.

Transpulmonary Pressure (Ptp)

• Transpulmonary pressure (Ptp) represents the difference between intrapulmonary and intrapleural pressures.

Transpulmonary Pressure During Inspiration

• Transpulmonary pressure increases as the thoracic volume increases during inspiration.

Effect of Decreased Transpulmonary Pressure

• Decreased transpulmonary pressure leads to lung collapse or atelectasis.

Brain Control of Breathing Rhythm

• The medulla oblongata primarily controls the basic rhythm of breathing.

Location of Peripheral Chemoreceptors

• Peripheral chemoreceptors are located in the carotid and aortic bodies.
• These receptors monitor carbon dioxide, pH, and oxygen levels in the blood.

Brain Areas for Voluntary Breathing

• The cerebral cortex is involved in the voluntary control of breathing (e.g., speaking or singing).

Function of the Pontine Respiratory Group (PRG)

• The pontine respiratory group (PRG) modulates the rate and depth of breathing.

Key Gas in Regulating Ventilation Rate

• Carbon dioxide is the most important gas in regulating the rate of ventilation.

Response of Peripheral Chemoreceptors to Low Oxygen

• Peripheral chemoreceptors trigger an increase in the rate of breathing when oxygen levels fall below 60 mmHg.

Effect of Increased Blood CO2 on pH

• An increase in blood CO2 concentration causes a decrease in blood pH (acidosis).

Hypoxic Hypoxia

• Hypoxic hypoxia occurs when there is inadequate oxygen diffusion from the alveoli into the blood, despite normal ventilation.

Anemic or Hypemic Hypoxia

• Anemic or hypemic hypoxia is caused by a reduced ability of blood to carry oxygen.

Histotoxic Hypoxia

• Histotoxic hypoxia occurs when there is normal oxygen content in the blood, but cells cannot effectively use the oxygen due to toxins or metabolic disturbances.

Circulatory or Ischemic Hypoxia

• Circulatory or ischemic hypoxia is described as decreased blood flow preventing oxygen from reaching tissues.

Hypoxia at High Altitudes

• Hypoxic hypoxia is most likely to occur at high altitudes due to decreased atmospheric oxygen pressure.

Location of the Pre-Bötzinger Complex

• The pre-Bötzinger complex is located in the VRG (Ventral Respiratory Group).

Role of the Pontine Respiratory Group (PRG)

• The pontine respiratory group (PRG) plays a key role in modulating the rate and depth of breathing.

Effect of Damage to the Pons

• Damage to the pons typically causes abnormal and irregular breathing patterns, such as apneustic or ataxic breathing.

Function of the Pneumotaxic Center

• The pneumotaxic center of the pons is primarily responsible for terminating inspiration and regulating inspiratory volume.

Nephron and Reabsorption

• The proximal convoluted tubule is primarily responsible for the reabsorption of most of the filtered water and solutes in the nephron.

Descending Limb of the Loop of Henle

• The descending limb of the Loop of Henle is highly permeable to water, leading to water reabsorption.

Ion Reabsorption in the Ascending Limb

• Sodium is actively reabsorbed in the thick ascending limb of the Loop of Henle.

Collecting Duct Regulation by Aldosterone

• Water reabsorption in the collecting duct is primarily regulated by aldosterone.

Site of Glucose Reabsorption

• The majority of glucose reabsorption occurs in the proximal convoluted tubule of the nephron.

Function of the Countercurrent Multiplier System

• The countercurrent multiplier system in the Loop of Henle generates a concentration gradient that allows for the reabsorption of water in the collecting duct.

Hormonal Control of Water Reabsorption

• Antidiuretic hormone (ADH) primarily controls water reabsorption in the collecting duct.

Respiratory Alkalosis

• A patient with rapid breathing, dizziness, decreased partial pressure of carbon dioxide (PaCO₂) in the blood, and a pH of 7.48 is most likely experiencing respiratory alkalosis.

Respiratory Acidosis

• A patient with a pH of 7.30, bicarbonate (HCO₃⁻) of 24 mEq/L, and an elevated partial pressure of carbon dioxide (PaCO₂) is most likely experiencing respiratory acidosis.

Metabolic Alkalosis

• A patient with a pH of 7.50 and bicarbonate (HCO₃⁻) levels of 30 mEq/L and a PCO₂ of 30mmHg is most likely experiencing metabolic alkalosis.

Glomerular Filtration

• Glomerular capillary hydrostatic pressure promotes the movement of fluid from the glomerular capillaries into the Bowman's capsule during glomerular filtration.

Forces Opposing Glomerular Filtration

• Glomerular capillary oncotic pressure opposes glomerular filtration by pulling fluid back into the glomerular capillaries.