BIO 202 Respiratory Final Exam Review Guide

Absolutely, Sarah! Here's a comprehensive and structured review guide tailored to your BIO 202 Respiratory Final. I’ve organized it into digestible sections with bullet points and key terms to help you master each concept.

🫁 1. Structures & Functions of the Respiratory System

Upper Respiratory Tract

• Nose & Nasal Cavity: Filters, warms, humidifies air

• Pharynx: Passageway for air and food

• Larynx: Voice production; protects lower tract during swallowing

Lower Respiratory Tract

• Trachea: Windpipe; conducts air to bronchi

• Bronchi & Bronchioles: Branching airways; regulate airflow

• Alveoli: Site of gas exchange

• Lungs: House alveoli; facilitate ventilation

🫧 2. Alveolar Structure & Gas Exchange

• Alveoli: Thin-walled sacs surrounded by capillaries

• Type I cells: Gas exchange

• Type II cells: Secrete surfactant to reduce surface tension

• Gas exchange: Driven by partial pressure gradients (O₂ in, CO₂ out)

🌬 3. Respiratory Tract Structures & Pressures

• Airflow: Moves from high to low pressure

• Intrapulmonary pressure: Pressure inside alveoli

• Intrapleural pressure: Always negative to keep lungs inflated

• Transpulmonary pressure: Difference between the two; drives lung expansion

🧠 4. Pons & Medulla Oblongata Functions

• Medulla:

  • Dorsal respiratory group (DRG): Controls inspiration

  • Ventral respiratory group (VRG): Controls forced expiration

• Pons:

  • Apneustic center: Stimulates inspiration

  • Pneumotaxic center: Inhibits inspiration for rhythm control

⚗ 5. Gas Laws in Breathing & Exchange

📊 6. Lung Volumes & Capacities

🌀 7. Resistance & Airflow

• Airflow ∝ Pressure / Resistance

• Resistance ↑ with:

  • Bronchoconstriction

  • Mucus/inflammation

• Airflow ↓ with:

  • Narrow airways

  • High resistance

🔄 8. Internal vs External Respiration

• External: Gas exchange between alveoli & blood

  • Influenced by partial pressures, membrane thickness, surface area

• Internal: Gas exchange between blood & tissues

  • Driven by cellular metabolism and pressure gradients

🩸 9. CO₂ Transport in Blood

• Dissolved in plasma (~7%)

• Bound to hemoglobin as carbaminohemoglobin (~23%)

• As bicarbonate (HCO₃⁻) via carbonic anhydrase (~70%)

🌎 10. Atmospheric Gases

📈 11. Oxygen Dissociation Curve, Carbonic Anhydrase, Carbaminohemoglobin

• O₂ Dissociation Curve: Sigmoidal; shows hemoglobin’s affinity for O₂

  • Shift right: ↓ affinity (↑ CO₂, ↑ temp, ↓ pH)

  • Shift left: ↑ affinity

• Carbonic Anhydrase: Enzyme converting CO₂ + H₂O ↔ H₂CO₃ ↔ H⁺ + HCO₃⁻

• Carbaminohemoglobin: CO₂ bound to hemoglobin (not at O₂ binding site)

🧪 12. Bohr & Haldane Effects

• Bohr Effect: ↑ CO₂ or ↓ pH → ↓ hemoglobin affinity for O₂

• Haldane Effect: Deoxygenated hemoglobin binds CO₂ more readily

😮‍💨 13. Hyperventilation vs Hypoventilation

🧬 14. Neuronal Control of Breathing

• Central chemoreceptors: Detect CO₂ & pH in CSF

• Peripheral chemoreceptors: Detect O₂, CO₂, pH in blood (carotid/aortic bodies)

• Stretch receptors: Prevent overinflation (Hering-Breuer reflex)

💪 15. Muscles of Ventilation & Thoracic Pressure

Primary Muscles

• Diaphragm: Contracts → ↑ thoracic volume

• External intercostals: Elevate ribs

Accessory Muscles

• Inspiration: Sternocleidomastoid, scalenes

• Expiration (forced): Internal intercostals, abdominal muscles

Absolutely, Sarah! Here’s your BIO 202 Respiratory System Lecture Notes, written in simple language, organized like classroom-style slides, and ready to be turned into flashcards or study sheets. I’ll keep the explanations clear, conversational, and include emoji cues to make it easier to visualize.

🫁 Lecture 1: Overview of the Respiratory System

🔹 Main Jobs:

• Bring oxygen into your body 💨

• Remove carbon dioxide 🫶

🔹 Two Main Zones:

• Upper Tract: Nose, nasal cavity, pharynx, larynx – filters, warms, and moistens air

• Lower Tract: Trachea, bronchi, lungs, alveoli – passes and exchanges gases

🫧 Lecture 2: Alveoli & Gas Exchange

🔹 Alveoli = tiny air sacs (like grapes)

• Very thin walls

• Surrounded by capillaries 🩸

🔹 Gas Exchange:

• O₂ moves from alveoli → blood

• CO₂ moves from blood → alveoli

Think of them as “swap stations” where oxygen and carbon dioxide trade places.

🌬 Lecture 3: Breathing Pressures

🔹 Air moves from high to low pressure

• When chest expands → pressure drops → air rushes in

• When chest shrinks → pressure rises → air goes out

🔹 Key Pressures:

• Intrapulmonary (inside lungs)

• Intrapleural (between lungs and chest wall) – always negative to keep lungs open

🧠 Lecture 4: Brain Control (Pons & Medulla)

🔹 Medulla:

• Controls normal breathing rhythm

• Turns breathing on and off like a switch

🔹 Pons:

• Smooths breathing

• Coordinates inhale & exhale timing

⚗ Lecture 5: Gas Laws Made Easy

• Boyle’s Law: Bigger space = lower pressure

• Dalton’s Law: Air is made of lots of gases

• Henry’s Law: Gases dissolve based on pressure

• Fick’s Law: More surface area = better gas exchange

📊 Lecture 6: Lung Volumes

🌀 Lecture 7: Resistance & Airflow

🔹 Narrow tubes = harder to breathe

• Conditions like asthma or mucus increase resistance

• Air wants to flow freely, but blockages slow it down

🔄 Lecture 8: Internal vs External Respiration

• External: Alveoli ↔ Blood (lungs)

• Internal: Blood ↔ Cells (body tissues)

🩸 Lecture 9: CO₂ Transport

• Dissolved in plasma: Small amount

• Bicarbonate: Most common (70%)

• Carbaminohemoglobin: Attached to hemoglobin

🌎 Lecture 10: Air Composition

• Nitrogen: 78%

• Oxygen: 21%

• Others (CO₂, water vapor, etc.): 1%

📈 Lecture 11: Oxygen & CO₂ Exchange Helpers

• Dissociation Curve: Shows how oxygen loads & unloads

• Carbonic Anhydrase: Converts CO₂ into transportable form

• Carbaminohemoglobin: CO₂ stuck to hemoglobin

🧪 Lecture 12: Haldene vs Bohr Effects

😮‍💨 Lecture 13: Breathing Imbalances

• Hyperventilation = breathing too fast → low CO₂

• Hypoventilation = breathing too slow → high CO₂

🧬 Lecture 14: Nerve Control

• Central sensors: Detect CO₂/pH in brain

• Peripheral sensors: Detect gases in blood

• Stretch receptors: Prevent lungs from overfilling

💪 Lecture 15: Breathing Muscles

They change chest space to control pressure, letting air in or out.