Exam

Perfect! That’s the best approach. We’ll go through every objective in order, and I’ll make each section detailed enough that by the end you’ll have a complete study guide for your exam.

Section 1: Objectives 1–8

(Based on your objectives and the PowerPoint.)

Objective 1: Describe the 4 Major Processes of Respiration

Respiration is the overall process of supplying oxygen (O₂) to body tissues and removing carbon dioxide (CO₂). It occurs in 4 major steps:

1. Pulmonary Ventilation (Breathing)

Movement of air into and out of the lungs.
Includes:
- Inspiration (breathing in)
- Expiration (breathing out)

Purpose: Bring oxygen into the lungs and remove carbon dioxide.

2. External Respiration

Occurs between:

Alveoli
Pulmonary capillaries

Here:

Oxygen diffuses from alveoli → blood.
Carbon dioxide diffuses from blood → alveoli.

Blood changes from:

Deoxygenated → Oxygenated

3. Transport of Respiratory Gases

Blood transports gases throughout the body.

Oxygen:

98.5% attached to hemoglobin
1.5% dissolved in plasma

Carbon dioxide:

Mostly bicarbonate ions
Carbaminohemoglobin
Dissolved in plasma

4. Internal Respiration

Occurs between:

Systemic capillaries
Body tissues

Here:

Oxygen leaves blood and enters cells.
Carbon dioxide leaves cells and enters blood.

Blood changes from:

Oxygenated → Deoxygenated

Easy Memory Trick

PETI

P = Pulmonary ventilation

E = External respiration

T = Transport

I = Internal respiration

Objective 2: Distinguish Upper vs Lower Respiratory Tracts

Upper Respiratory Tract

Includes:

Nose
Nasal cavity
Paranasal sinuses
Pharynx

Functions

Warm air
Humidify air
Filter air
Smell
Speech resonance

Lower Respiratory Tract

Includes

Larynx
Trachea
Bronchi
Bronchioles
Alveoli
Lungs

Functions

Conduct air
Gas exchange
Voice production (larynx)

Exam Tip

Upper = Mostly prepares air.

Lower = Conducts air and performs gas exchange.

Objective 3: Conducting Zone vs Respiratory Zone

Conducting Zone

Purpose:
Moves air only.

Includes:

Nose
Nasal cavity
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Terminal bronchioles

Functions

Filters air
Warms air
Moistens air

NO gas exchange occurs here.

Respiratory Zone

Purpose:
Gas exchange.

Includes

Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli

Contains approximately 300 million alveoli, providing a huge surface area for gas exchange.

22, Respiratory Vu (11 ed).ppt

Memory Trick

Conducting = Conducts

Respiratory = Respiration (gas exchange)

Objective 4: Trace Air From Nostril to Alveoli

Know this pathway in order:

Nostrils (nares)

↓

Nasal cavity

↓

Nasopharynx

↓

Oropharynx

↓

Laryngopharynx

↓

Larynx

↓

Trachea

↓

Carina

↓

Primary bronchi

↓

Secondary bronchi

↓

Tertiary bronchi

↓

Bronchioles

↓

Terminal bronchioles

↓

Respiratory bronchioles

↓

Alveolar ducts

↓

Alveolar sacs

↓

Alveoli

Bronchi Numbers

Primary bronchi = 2

Secondary bronchi = 5

Right = 3
Left = 2

Tertiary bronchi = 20 total

10 in each lung

Structure	Function	Epithelium
Nasal cavity	Warm/filter air	Pseudostratified ciliated columnar (except olfactory area)
Nasopharynx	Air only	Pseudostratified ciliated columnar
Oropharynx	Food & air	Stratified squamous
Laryngopharynx	Food & air	Stratified squamous
Trachea	Conduct air	Pseudostratified ciliated columnar with goblet cells
Bronchi	Conduct air	Pseudostratified ciliated columnar
Bronchioles	Conduct air	Simple cuboidal
Alveoli	Gas exchange	Simple squamous (Type I cells)

Objective 6: Paranasal Sinuses

These are air-filled cavities in the skull surrounding the nasal cavity.

Functions

Lighten skull weight
Warm inspired air
Humidify air
Produce mucus
Improve voice resonance

Types

Frontal
Maxillary
Ethmoid
Sphenoid

Objective 7: Nasal Cavity

The nasal cavity lies behind the nose and is divided by the nasal septum.

Vestibule

Area just inside the nostrils.
Contains vibrissae (nose hairs) that trap large particles.

Olfactory Mucosa

Located in the superior nasal cavity.
Contains smell receptors.

Respiratory Mucosa

Covers most of the nasal cavity.
Goblet cells produce mucus.
Cilia move mucus toward the pharynx.
Mucus contains lysozyme and defensins, which help destroy bacteria.

Objective 9: Describe the Components of the Larynx

What is the Larynx?

The larynx (voice box) connects the laryngopharynx to the trachea.

Location

Inferior to the pharynx
Superior to the trachea
Attached to the hyoid bone

Three Main Functions

1. Maintain an open airway

Allows air to travel into the lungs.

2. Direct food and air

Acts like a traffic controller.

Food ➜ Esophagus

Air ➜ Trachea

3. Voice Production

Contains the vocal folds that vibrate to produce sound.

Cartilages of the Larynx

Thyroid Cartilage

Largest cartilage
Hyaline cartilage
Forms the Adam’s apple
Protects vocal cords

Cricoid Cartilage

Ring-shaped
Located below thyroid cartilage
Only complete cartilage ring around the airway

Epiglottis

Elastic cartilage

Function:

Covers the laryngeal opening during swallowing.
Prevents food from entering the trachea.

Remember:

Epiglottis = “Food Stopper”

Three Pairs of Small Cartilages

Know these for the exam.

Arytenoid Cartilages

Most important.

Functions:

Anchor vocal cords
Open and close glottis
Control speaking

Cuneiform Cartilages

Support soft tissues.

Corniculate Cartilages

Support arytenoids.

Easy Mnemonic

A C C

Arytenoid

Corniculate

Cuneiform

Objective 10: Vocal Production

True Vocal Cords

Made of elastic fibers.

Function:

Produce sound.

False Vocal Cords

Located above true cords.

Function:

Protection only.

NO sound production.

Glottis

Opening between true vocal cords.

Pitch

Determined by

Length
Tension

Higher tension

↓

Higher pitch

Loudness

Determined by

Force of air passing over vocal cords.

More air

↓

Louder voice

Speech Formation

Sound is shaped by

Tongue
Lips
Soft palate
Pharynx

Think:

Vocal cords make sound.

Mouth shapes words.

Objective 11: Trachea

The trachea is a flexible airway connecting the larynx to the bronchi.

Functions

Conduct air
Filter air
Warm air
Humidify air

Position

Extends from

Larynx

↓

Carina

↓

Primary bronchi

Layers of the Trachea

1. Mucosa

Contains

Goblet cells
Ciliated pseudostratified columnar epithelium

Goblet cells produce mucus.

Cilia move mucus upward.

2. Submucosa

Contains

Connective tissue
Blood vessels
Seromucous glands

3. Adventitia

Contains

C-shaped hyaline cartilage rings.

Purpose:

Prevent airway collapse.

Trachealis Muscle

Located posteriorly.

Function:

Narrows trachea during coughing.

Allows esophagus to expand during swallowing.

Objective 8: Pharynx

The pharynx is a funnel-shaped muscular tube connecting the nasal and oral cavities to the larynx and esophagus.

1. Nasopharynx

Air passage only.
Lined with pseudostratified ciliated columnar epithelium.
Contains the pharyngeal tonsil.
Connected to the auditory (Eustachian) tubes.

2. Oropharynx

Common passageway for food and air.
Lined with stratified squamous epithelium.
Contains the palatine and lingual tonsils.

3. Laryngopharynx

Common passageway for food and air.
Extends to the larynx and esophagus, where the respiratory and digestive pathways diverge.

Objective 12: Bronchial Tree

Know this pathway perfectly.

Trachea

↓

Carina

↓

Primary bronchi

↓

Secondary bronchi

↓

Tertiary bronchi

↓

Bronchioles

↓

Terminal bronchioles

↓

Respiratory bronchioles

↓

Alveolar ducts

↓

Alveolar sacs

↓

Alveoli

Number of Bronchi

Primary = 2

Secondary = 5

Right = 3

Left = 2

Tertiary = 20

10 in each lung.

Structural Changes

As airways get smaller:

Cartilage

↓

Decreases

Smooth Muscle

↓

Increases

Goblet Cells

↓

Disappear

Epithelium

Changes from

Pseudostratified columnar

↓

Simple cuboidal

↓

Simple squamous

Bronchioles

Remember

NO cartilage

NO goblet cells

Complete layer of circular smooth muscle.

This is why asthma causes bronchoconstriction.

Objective 13: Alveoli & Respiratory Membrane

The alveoli are tiny air sacs where gas exchange occurs.

Approximately

300 million alveoli

Huge surface area for diffusion.

Type I Cells

Simple squamous epithelial cells.

Functions

Form alveolar wall
Gas exchange
Produce ACE (angiotensin-converting enzyme)

Type II Cells

Functions

Produce pulmonary surfactant.

Surfactant

A lipid-protein substance.

Function

Reduces surface tension.

Keeps alveoli open.

Without surfactant

↓

Alveoli collapse (atelectasis).

Premature infants may develop infant respiratory distress syndrome (IRDS) because they do not produce enough surfactant.

Alveolar Macrophages

“Dust cells”

Functions

Eat bacteria
Remove debris
Clean alveoli

Respiratory Membrane

Extremely thin.

Consists of

Type I alveolar cell
Fused basement membrane
Capillary endothelium

Purpose

Allows oxygen and carbon dioxide to diffuse quickly.

Objective 14: Lung Anatomy

The lungs occupy most of the thoracic cavity except the mediastinum.

Surfaces

Apex

Superior tip.

Base

Rests on diaphragm.

Costal Surface

Touches ribs.

Hilum (Hilus)

Entry point for

Bronchi
Pulmonary arteries
Pulmonary veins
Nerves
Lymphatics

Lobes

Right Lung

Three lobes

Superior
Middle
Inferior

Separated by

Horizontal fissure
Oblique fissure

Left Lung

Two lobes

Superior
Inferior

Separated by

Oblique fissure

Has a cardiac notch for the heart.

Bronchopulmonary Segments

Functional subdivisions of each lung supplied by one tertiary bronchus.

There are 10 segments in each lung.

Clinical significance:

A diseased segment can sometimes be removed without removing the whole lung.

Objective 15: Pleural Membranes

The pleurae are thin, double-layered serous membranes surrounding the lungs.

Parietal Pleura

Lines the thoracic wall and diaphragm.

Visceral Pleura

Covers the outer surface of the lungs.

Pleural Cavity

The small space between the pleural layers.

Contains pleural fluid.

Functions of Pleural Fluid

Lubricates the lungs
Reduces friction during breathing
Creates surface tension that helps keep the lungs expanded

Objective 16: High-Yield Review

Know These Numbers

Primary bronchi = 2
Secondary bronchi = 5
Tertiary bronchi = 20
Lung lobes = Right 3, Left 2
Bronchopulmonary segments = 10 per lung
Alveoli = ~300 million

Epithelium Progression

Nasal cavity & trachea → Pseudostratified ciliated columnar
Bronchioles → Simple cuboidal
Alveoli → Simple squamous (Type I cells)

Cartilage Progression

Trachea → C-shaped cartilage
Bronchi → Cartilage plates
Bronchioles → No cartilage

Objective 17: Describe Boyle’s Law and How It Explains Pulmonary Ventilation

Boyle’s Law

Boyle’s Law states:

As the volume increases, pressure decreases.

As the volume decreases, pressure increases.

22, Respiratory Vu (11 ed).ppt

Why?

Gas molecules spread farther apart when volume increases, so they hit the walls of the container less often, decreasing pressure.

How Boyle’s Law Applies to Breathing

During Inspiration

Thoracic cavity volume increases.

↓

Lung volume increases.

↓

Pressure inside the lungs decreases.

↓

Air flows into the lungs.

During Expiration

Thoracic cavity volume decreases.

↓

Lung volume decreases.

↓

Pressure inside the lungs increases.

↓

Air flows out of the lungs.

Memory Trick

Big lungs = Low pressure

Small lungs = High pressure

Objective 18: Quiet Inspiration

Quiet inspiration is an active process because muscles contract.

Step-by-Step

Step 1

Diaphragm contracts.

Moves downward (flattens).

Step 2

External intercostal muscles contract.

Ribs move:

Step 3

Thoracic cavity volume increases.

Step 4

Lungs stretch.

Intrapulmonary volume increases.

Step 5

Intrapulmonary pressure drops to about –1 mmHg.

Step 6

Air flows into the lungs until lung pressure equals atmospheric pressure.

Objective 19: Quiet Expiration

Quiet expiration is normally a passive process.

No muscle contraction is required.

Step-by-Step

Step 1

Diaphragm relaxes.

Moves upward.

Step 2

External intercostals relax.

Ribs fall downward.

Step 3

Thoracic cavity volume decreases.

Step 4

Elastic lungs recoil.

Step 5

Intrapulmonary pressure rises to about +1 mmHg.

Step 6

Air leaves the lungs until pressure equals atmospheric pressure.

Muscle	Action
Diaphragm	Relaxes
External intercostals	Relax
Thoracic volume	Decreases
Lung pressure	Increases
Air movement	Out of lungs

Which process is active?

✔ Inspiration

Which process is passive?

✔ Quiet expiration

Objective 20: Factors Affecting Airflow

Three major factors influence pulmonary ventilation:

Airway resistance
Alveolar surface tension
Lung compliance

22, Respiratory Vu (11 ed).ppt

Airway Resistance

Resistance is friction that opposes airflow.

Formula from the slides:

Flow (F) = Pressure gradient (ΔP) ÷ Resistance (R)

22, Respiratory Vu (11 ed).ppt

Increased Resistance

Causes:

Asthma
Bronchoconstriction
Excess mucus

Result:

Harder to breathe.

Decreased Resistance

Occurs with bronchodilation.

Example:

Epinephrine relaxes bronchioles and reduces resistance.

22, Respiratory Vu (11 ed).ppt

Surface Tension

Water molecules inside alveoli naturally attract each other.

This creates surface tension that tends to collapse alveoli.

Surfactant

Produced by:

Type II alveolar cells

Functions:

Reduces surface tension
Prevents alveolar collapse
Makes breathing easier

Premature infants with too little surfactant can develop infant respiratory distress syndrome (IRDS).

22, Respiratory Vu (11 ed).ppt

Lung Compliance

Compliance = How easily the lungs stretch.

High compliance:

Easy to inflate lungs.

Low compliance:

Difficult to inflate lungs.

Causes of Low Compliance

Fibrosis (scar tissue)
Reduced surfactant
Decreased flexibility of the thoracic cage
Thoracic deformities
Ossification of costal cartilage
Paralysis of intercostal muscles

22, Respiratory Vu (11 ed).ppt

Objective 21: Muscles of Breathing

Quiet Inspiration

Main muscles:

Diaphragm

Most important muscle.

Responsible for most normal breathing.

External Intercostals

Lift ribs.

Increase chest diameter.

Forced Inspiration

Occurs during exercise or deep breathing.

Uses:

Sternocleidomastoid
Scalenes
Pectoralis minor
Serratus posterior superior
Erector spinae

22, Respiratory Vu (11 ed).ppt

Forced Expiration

Normally expiration is passive.

Forced expiration uses:

Internal intercostals
External oblique
Transversus abdominis
Transversus thoracis
Serratus posterior inferior

Quiet Inspiration	Forced Inspiration	Forced Expiration
Diaphragm	Sternocleidomastoid	Internal intercostals
External intercostals	Scalenes	Abdominal muscles
Pectoralis minor	Transversus thoracis

Objective 22: Pneumothorax

Definition

Air enters the pleural cavity because the sealed pleural space is opened.

This causes:

Loss of negative pressure
Lung collapse (atelectasis) on the affected side

22, Respiratory Vu (11 ed).ppt

Causes

Gunshot wounds
Knife wounds
Broken ribs
Chest trauma

Symptoms

Sudden chest pain
Shortness of breath
Collapsed lung

Objective 23: Breathing Patterns

Eupnea

Normal quiet breathing.

Apnea

Temporary absence of breathing.

Dyspnea

Difficult or labored breathing.

Occurs in:

COPD
Asthma
Heart failure

Note on Cheyne-Stokes

Your objectives mention Cheyne-Stokes, but the uploaded PowerPoint section provided here does not define or explain it. Since we’re staying grounded in your course materials, I can’t add details that aren’t supported by the uploaded slides.

Objectives Respiratory System.docx

Objective 24: Modified Respiratory Movements

Coughing

Purpose:

Clear the respiratory passages.

Steps:

Deep inspiration
Glottis closes
Strong expiration blasts air out

Hiccuping

Caused by:

Sudden spasmodic contraction of the diaphragm
Rapid closure of the glottis

Produces the characteristic “hic” sound.

22, Respiratory Vu (11 ed).ppt

⭐ Exam Memory Box

Boyle’s Law

↑ Volume = ↓ Pressure
↓ Volume = ↑ Pressure

Inspiration

Active
Diaphragm contracts
Pressure ↓
Air enters

Expiration

Passive (quiet)
Diaphragm relaxes
Pressure ↑
Air leaves

Airflow Factors

Airway resistance
Surface tension
Lung compliance

Surfactant

Made by Type II cells
Lowers surface tension
Prevents alveolar collapse

Pneumothorax

Air in pleural cavity
Causes lung collapse (atelectasis)

Breathing Terms

Eupnea = normal breathing
Apnea = no breathing
Dyspnea = difficult breathing

Objective 25: Describe Lung Volumes and Capacities

A lung volume is the amount of air moved during a specific part of breathing.

A lung capacity is the sum of two or more lung volumes.

1. Tidal Volume (TV)

Amount of air inhaled or exhaled during normal quiet breathing.

Normal value:

500 mL (0.5 L)

2. Inspiratory Reserve Volume (IRV)

The extra air you can inhale after a normal inspiration.

Think:
Normal breath + deepest breath possible.

3. Expiratory Reserve Volume (ERV)

The extra air you can force out after a normal expiration.

4. Residual Volume (RV)

Air that remains in the lungs after the strongest possible expiration.

Purpose:

Prevents lung collapse.
Keeps alveoli open.

Lung Capacities

Vital Capacity (VC)

Maximum amount of air that can be moved.

Formula:

VC = TV + IRV + ERV

This is one of the most important formulas to memorize.

Objectives Respiratory System.docx

Total Lung Capacity (TLC)

Maximum amount of air the lungs can hold.

Formula:

TLC = VC + RV

TV	Normal breath
IRV	Extra air in
ERV	Extra air out
RV	Air left after maximal exhalation
VC	TV + IRV + ERV
TLC	VC + RV

Objective 26: Spirometer

A spirometer measures the amount of air entering and leaving the lungs.

Uses:

Measures lung volumes
Evaluates respiratory health
Helps diagnose lung disease
Monitors treatment progress

22, Respiratory Vu (11 ed).ppt

Incentive Spirometer

Purpose:

Encourages deep breathing after surgery.

Helps:

Prevent atelectasis
Improve lung expansion

Objective 27: Dead Space

Anatomical Dead Space

Definition:

Air in the conducting zone where no gas exchange occurs.

Normal value:

150 mL

Includes:

Nose
Pharynx
Larynx
Trachea
Bronchi
Bronchioles

Alveolar Ventilation

Air that actually reaches the alveoli each minute.

Formula:

(Tidal Volume − Anatomical Dead Space) × Respiratory Rate

Example from your slides:

(500 mL − 150 mL) × 12 = 4.2 L/min

22, Respiratory Vu (11 ed).ppt

Physiological Dead Space

Definition:

Anatomical dead space plus any alveoli that are not participating in gas exchange because of damage or disease (such as pneumonia). Normally, physiological dead space equals anatomical dead space.

22, Respiratory Vu (11 ed).ppt

Objective 28: Dalton’s Law

Dalton’s Law states:

Each gas in a mixture exerts its own partial pressure independently of the other gases.

Total atmospheric pressure = 760 mmHg.

Partial pressure of oxygen:

760 × 21% = 160 mmHg.

22, Respiratory Vu (11 ed).ppt

Why It Matters

Gas exchange depends on partial pressure differences.

Oxygen moves:

High PO₂ → Low PO₂.

Carbon dioxide moves:

High PCO₂ → Low PCO₂.

Objective 29: Henry’s Law

Henry’s Law states:

The amount of gas that dissolves in a liquid depends on:

Pressure
Solubility of the gas

Examples from your slides:

Scuba diving
Nitrogen narcosis
Decompression sickness (“the bends”)
Hyperbaric oxygen therapy

22, Respiratory Vu (11 ed).ppt

Objective 30: Hyperbaric Oxygen Therapy

Hyperbaric oxygenation is a clinical application of Henry’s Law.

Patient breathes 100% oxygen inside a chamber with increased pressure (3–4 atmospheres).

This dissolves more oxygen into the blood and tissues.

Uses listed in your slides:

Anaerobic bacterial infections (tetanus, gangrene)
Carbon monoxide poisoning
Cerebral edema
Bone infections
Gas embolisms
Crush injuries
Some heart disorders

22, Respiratory Vu (11 ed).ppt

Objective 31: External Respiration

Occurs between:

Alveoli
Pulmonary capillaries

Oxygen:

Alveoli → Blood

Carbon dioxide:

Blood → Alveoli

Result:

Deoxygenated blood becomes oxygenated.

22, Respiratory Vu (11 ed).ppt

Objective 32: Internal Respiration

Occurs between:

Systemic capillaries
Body tissues

Oxygen:

Blood → Cells

Carbon dioxide:

Cells → Blood

Result:

Oxygenated blood becomes deoxygenated.

22, Respiratory Vu (11 ed).ppt

Objective 33: Ventilation–Perfusion (V/Q) Coupling

The slides state:

Decreased PO₂ → vasoconstriction of pulmonary arterioles
Increased PCO₂ → bronchodilation of bronchioles

This helps match airflow (ventilation) with blood flow (perfusion).

22, Respiratory Vu (11 ed).ppt

Objective 34: High-Yield Review

Lung Volumes

TV = Normal breath
IRV = Extra inhale
ERV = Extra exhale
RV = Air remaining

Important Formulas

VC = TV + IRV + ERV
TLC = VC + RV
Alveolar ventilation = (TV − Dead Space) × Respiratory Rate

Dead Space

Anatomical = Conducting zone only
Physiological = Anatomical + nonfunctioning alveoli

Gas Laws

Dalton’s Law: Partial pressures drive diffusion.
Henry’s Law: Higher pressure dissolves more gas in liquids.

External vs. Internal Respiration

External	Internal
Alveoli â†” Blood	Blood â†” Tissues
Blood gains Oâ‚‚	Tissues gain Oâ‚‚
Blood loses COâ‚‚	Blood gains COâ‚‚

Objective 35: Know the Percentages of O₂ and CO₂ Transported in Blood

Oxygen (O₂) Transport

There are two ways oxygen is transported:

1. Attached to Hemoglobin (98.5%)

Forms oxyhemoglobin (HbO₂).
This is the main way oxygen is transported.
Oxygen does not dissolve well in water, so it mostly travels attached to hemoglobin inside red blood cells.

22, Respiratory Vu (11 ed).ppt

2. Dissolved in Plasma (1.5%)

Only a small amount of oxygen travels dissolved in plasma.
Only dissolved oxygen can diffuse directly into tissues.

Easy Memory Trick

98.5% = Hemoglobin

1.5% = Plasma

Carbon Dioxide (CO₂) Transport

According to your slides, 100 mL of blood carries about 55 mL of CO₂.

CO₂ is transported in three ways:

1. As Bicarbonate Ions (Most)

CO₂ + H₂O → H₂CO₃ → HCO₃⁻ + H⁺

This is the primary method of CO₂ transport.

22, Respiratory Vu (11 ed).ppt

2. Attached to Hemoglobin

Forms carbaminohemoglobin (HbCO₂).

CO₂ binds to the globin portion of hemoglobin.

3. Dissolved in Plasma

A small amount travels freely dissolved in plasma.

Objective 36: Hemoglobin Saturation & Oxygen Affinity

Hemoglobin Saturation

Hemoglobin saturation is the percentage of oxygen-binding sites on hemoglobin that are occupied by oxygen.

High saturation = More oxygen is bound.
Low saturation = Less oxygen is bound.

Oxygen Affinity

Oxygen affinity refers to how strongly hemoglobin holds onto oxygen.

High affinity → Hemoglobin holds oxygen tightly and releases less to tissues.
Low affinity → Hemoglobin releases oxygen more easily to tissues.

22, Respiratory Vu (11 ed).ppt

Objective 37: Factors That Affect Oxygen Affinity

Your objectives list the Bohr effect (acidity), Haldane effect (increase CO₂), temperature, and BPG. The uploaded PowerPoint fully explains acidity (Bohr effect), increased CO₂, temperature, and BPG, but it does not define or explain the Haldane effect by name. Because we’re staying grounded in your course materials, I’ll only include what the slides specifically cover.

Objectives Respiratory System.docx

A. Bohr Effect (Acidity)

As acidity increases (pH decreases):

↓

Hemoglobin’s affinity for oxygen decreases.

↓

Hemoglobin releases more oxygen to tissues.

Reason given in the slides:

H⁺ binds to hemoglobin and alters it, leaving oxygen behind in needy tissues.

22, Respiratory Vu (11 ed).ppt

B. Increased CO₂

As PCO₂ increases (such as during exercise):

↓

More carbonic acid forms.

↓

More H⁺ is produced.

↓

pH decreases.

↓

Hemoglobin releases oxygen more easily.

22, Respiratory Vu (11 ed).ppt

C. Increased Temperature

As temperature increases:

↓

More oxygen is released.

The slides relate this to:

Increased metabolic activity
Heat production

22, Respiratory Vu (11 ed).ppt

D. Increased BPG

The slides state:

More BPG → More oxygen released.

22, Respiratory Vu (11 ed).ppt

Memory Trick

All of these cause more oxygen to leave hemoglobin:

↑ Acidity (Bohr effect)
↑ CO₂
↑ Temperature
↑ BPG

Objective 38: Carbon Monoxide Poisoning

Carbon monoxide (CO):

Comes from car exhaust and tobacco smoke.
Binds to hemoglobin more successfully than oxygen, preventing oxygen from binding.

22, Respiratory Vu (11 ed).ppt

Treatment

The slides state:

Administer pure oxygen.

Objective 39: Types of Hypoxia

Hypoxia = Deficiency of oxygen at the tissue level.

1. Hypoxic (Hypoxemic) Hypoxia

Cause:

Low PO₂ in arterial blood.

Examples:

High altitude
Fluid in lungs
Airway obstruction

2. Anemic Hypoxia

Cause:

Too little functioning hemoglobin.

Examples:

Hemorrhage
Anemia

SECTION 5: Objectives 35–42

Oxygen Transport, Hemoglobin Saturation, Bohr Effect, CO₂, Temperature, BPG, Carbon Monoxide Poisoning, Hypoxia & Carbon Dioxide Transport

(Based on your uploaded objectives and PowerPoint.)

Objective 35: Know the Percentages of O₂ and CO₂ Transported in Blood

Oxygen (O₂) Transport

There are two ways oxygen is transported:

1. Attached to Hemoglobin (98.5%)

Forms oxyhemoglobin (HbO₂).
This is the main way oxygen is transported.
Oxygen does not dissolve well in water, so it mostly travels attached to hemoglobin inside red blood cells.

22, Respiratory Vu (11 ed).ppt

2. Dissolved in Plasma (1.5%)

Only a small amount of oxygen travels dissolved in plasma.
Only dissolved oxygen can diffuse directly into tissues.

Easy Memory Trick

98.5% = Hemoglobin

1.5% = Plasma

Carbon Dioxide (CO₂) Transport

According to your slides, 100 mL of blood carries about 55 mL of CO₂.

CO₂ is transported in three ways:

1. As Bicarbonate Ions (Most)

CO₂ + H₂O → H₂CO₃ → HCO₃⁻ + H⁺

This is the primary method of CO₂ transport.

22, Respiratory Vu (11 ed).ppt

2. Attached to Hemoglobin

Forms carbaminohemoglobin (HbCO₂).

CO₂ binds to the globin portion of hemoglobin.

3. Dissolved in Plasma

A small amount travels freely dissolved in plasma.

Objective 36: Hemoglobin Saturation & Oxygen Affinity

Hemoglobin Saturation

Hemoglobin saturation is the percentage of oxygen-binding sites on hemoglobin that are occupied by oxygen.

High saturation = More oxygen is bound.
Low saturation = Less oxygen is bound.

Oxygen Affinity

Oxygen affinity refers to how strongly hemoglobin holds onto oxygen.

High affinity → Hemoglobin holds oxygen tightly and releases less to tissues.
Low affinity → Hemoglobin releases oxygen more easily to tissues.

22, Respiratory Vu (11 ed).ppt

Objective 37: Factors That Affect Oxygen Affinity

Objectives Respiratory System.docx

A. Bohr Effect (Acidity)

As acidity increases (pH decreases):

↓

Hemoglobin’s affinity for oxygen decreases.

↓

Hemoglobin releases more oxygen to tissues.

Reason given in the slides:

H⁺ binds to hemoglobin and alters it, leaving oxygen behind in needy tissues.

22, Respiratory Vu (11 ed).ppt

B. Increased CO₂

As PCO₂ increases (such as during exercise):

↓

More carbonic acid forms.

↓

More H⁺ is produced.

↓

pH decreases.

↓

Hemoglobin releases oxygen more easily.

22, Respiratory Vu (11 ed).ppt

C. Increased Temperature

As temperature increases:

↓

More oxygen is released.

The slides relate this to:

Increased metabolic activity
Heat production

22, Respiratory Vu (11 ed).ppt

D. Increased BPG

The slides state:

More BPG → More oxygen released.

22, Respiratory Vu (11 ed).ppt

Memory Trick

All of these cause more oxygen to leave hemoglobin:

↑ Acidity (Bohr effect)
↑ CO₂
↑ Temperature
↑ BPG

Objective 38: Carbon Monoxide Poisoning

Carbon monoxide (CO):

Comes from car exhaust and tobacco smoke.
Binds to hemoglobin more successfully than oxygen, preventing oxygen from binding.

22, Respiratory Vu (11 ed).ppt

Treatment

The slides state:

Administer pure oxygen.

Objective 39: Types of Hypoxia

Hypoxia = Deficiency of oxygen at the tissue level.

1. Hypoxic (Hypoxemic) Hypoxia

Cause:

Low PO₂ in arterial blood.

Examples:

High altitude
Fluid in lungs
Airway obstruction

2. Anemic Hypoxia

Cause:

Too little functioning hemoglobin.

Examples:

Hemorrhage
Anemia

3. Ischemic (Stagnant) Hypoxia

Cause:

Blood flow is too low.

4. Histotoxic Hypoxia

Cause:

Cyanide poisoning.

Cyanide blocks cells from using oxygen.

22, Respiratory Vu (11 ed).ppt

Objective 40: Carbon Dioxide Equation

Know this equation exactly:

CO₂ + H₂O ⇌ H₂CO₃ ⇌ HCO₃⁻ + H⁺

What it means:

CO₂ combines with water.
Carbonic acid (H₂CO₃) forms.
Carbonic acid breaks into:
- Bicarbonate (HCO₃⁻)
- Hydrogen ions (H⁺)

This is the main way CO₂ is transported in the blood.

22, Respiratory Vu (11 ed).ppt

Objective 41: Carbon Dioxide Transport at the Tissues

At body tissues:

Oxygen leaves the blood and enters tissues.
Carbon dioxide enters the blood.
Inside red blood cells, carbonic anhydrase rapidly converts CO₂ and H₂O into carbonic acid, which then dissociates into bicarbonate and H⁺.
Bicarbonate leaves the red blood cell in exchange for chloride ions (the chloride shift shown in the figure).

22, Respiratory Vu (11 ed).ppt

Objective 42: Carbon Dioxide Transport at the Lungs

At the lungs:

Oxygen enters the blood.
Carbon dioxide leaves the blood and enters the alveoli.
The reactions reverse so bicarbonate is converted back into CO₂, which is exhaled.
Chloride ions move back out of the red blood cell (reverse chloride shift).

22, Respiratory Vu (11 ed).ppt

⭐ HIGH-YIELD EXAM REVIEW

Oxygen Transport

98.5% attached to hemoglobin (oxyhemoglobin)
1.5% dissolved in plasma

Carbon Dioxide Transport

Three methods:

Bicarbonate ions (main method)
Carbaminohemoglobin
Dissolved in plasma

Factors That Cause More O₂ Release

✔ Increased acidity (Bohr effect)

✔ Increased CO₂

✔ Increased temperature

✔ Increased BPG

Carbon Monoxide

Binds hemoglobin more strongly than oxygen.
Treatment: Pure oxygen.

Type	Cause
Hypoxic	Low arterial POâ‚‚
Anemic	Low functioning hemoglobin
Ischemic	Poor blood flow
Histotoxic	Cells canâ€™t use oxygen (cyanide)

Objective 43: How Do DRG, VRG, and PRG Regulate Respiration?

The respiratory centers are located in the brainstem.

There are three major respiratory groups:

1. Dorsal Respiratory Group (DRG)

Located in the medulla.

Function

Controls quiet inspiration.
Sends nerve impulses to the diaphragm and external intercostal muscles.
Determines inspiratory depth.

2. Ventral Respiratory Group (VRG)

Located in the medulla.

Function

Mainly active during forced breathing.
Stimulates muscles used in forceful inspiration and expiration.

3. Pontine Respiratory Group (PRG)

Located in the pons.

Function

Modifies the activity of the medullary centers.
Smooths the transition between inspiration and expiration.
Continuously inhibits the inspiratory center.

22, Respiratory Vu (11 ed).ppt

Objective 44: Sympathetic vs. Parasympathetic Effects

Your objectives ask you to know the effects of the sympathetic and parasympathetic nervous systems. However, the uploaded PowerPoint does not specifically explain these effects, so I can’t add details beyond what your course materials provide.

Objectives Respiratory System.docx

Objective 45: Factors Influencing Respiratory Rate and Depth

The slides list four major factors.

1. Pulmonary Irritant Reflexes

Receptors are located throughout the lungs and are mediated by the vagus nerve.

Triggered by:

Dust
Mucus
Smoke
Noxious fumes

Effects:

Bronchioles constrict
Trachea and bronchi initiate coughing
Nasal cavity initiates sneezing

22, Respiratory Vu (11 ed).ppt

2. Inflation Reflex (Hering–Breuer Reflex)

Stretch receptors are located in the lungs and visceral pleura.

When lungs become overinflated:

Stretch receptors send inhibitory signals to the medulla via the vagus nerve.
Inspiration stops.
Expiration begins.

22, Respiratory Vu (11 ed).ppt

3. Higher Brain Centers

Hypothalamus

Strong emotions and pain can change breathing.

Examples:

Anger
Fear
Excitement
Sharp pain

Cerebral Cortex

Allows voluntary control of breathing.

Example:

Holding your breath

This control is limited because rising CO₂ eventually causes the medulla to resume breathing automatically.

22, Respiratory Vu (11 ed).ppt

4. Chemical Factors

The most powerful stimulus regulating breathing is PCO₂ (carbon dioxide).

Normal PCO₂:

37–43 mmHg
About 40 mmHg on average.

Central chemoreceptors respond rapidly when CO₂ changes.

22, Respiratory Vu (11 ed).ppt

Objective 46: Hypercapnia vs. Hypocapnia

Hypercapnia

Definition:

Increased CO₂ in the blood.

Process:

CO₂ diffuses into cerebrospinal fluid (CSF).
Carbonic acid forms.
H⁺ increases.
Central chemoreceptors are stimulated.
Breathing becomes deeper and may become faster (hyperventilation) to remove excess CO₂.

22, Respiratory Vu (11 ed).ppt

Hypocapnia

Definition:

Decreased CO₂ in the blood.

Effects:

Breathing becomes slow and shallow (hypoventilation).
Anxiety-induced hyperventilation can lower CO₂ so much that cerebral vasoconstriction causes dizziness or fainting.
The slides recommend sitting down and placing the head over the knees.

22, Respiratory Vu (11 ed).ppt

Objective 47: Central vs. Peripheral Chemoreceptors

Central Chemoreceptors

Location:

Brainstem

Respond primarily to:

Increased CO₂
Increased H⁺

They are the main regulators of normal breathing.

22, Respiratory Vu (11 ed).ppt

Peripheral Chemoreceptors

Location:

Carotid bodies
Aortic bodies

Respond mainly to:

Low oxygen (PO₂)

According to the slides:

Under normal conditions, the effect of declining PO₂ is limited.
PO₂ becomes a significant stimulus only when it falls below 60 mmHg.

22, Respiratory Vu (11 ed).ppt

Objective 48: Hypoxic Drive

Normally:

CO₂ controls breathing.

However, in chronic pulmonary diseases such as:

Emphysema
Chronic bronchitis

Persistent elevation of CO₂ makes central chemoreceptors less sensitive.

Then:

Low oxygen becomes the major stimulus for breathing.

This is called hypoxic drive.

22, Respiratory Vu (11 ed).ppt

Objective 49: Influence of Arterial pH

Even without changes in PO₂ or PCO₂:

Accumulation of acids such as:

Lactic acid
Fatty acids
Other organic acids

Increases ventilation.

This response is mediated by peripheral chemoreceptors.

22, Respiratory Vu (11 ed).ppt

Objective 50: COPD

COPD = Chronic Obstructive Pulmonary Disease

Examples:

Chronic bronchitis
Emphysema

Common history:

Smoking

Symptoms:

Progressive dyspnea
Chronic cough
Frequent pulmonary infections

Advanced COPD may cause:

Respiratory failure
Hypoxemia
Carbon dioxide retention
Respiratory acidosis

22, Respiratory Vu (11 ed).ppt

Objective 51: Emphysema

Characteristics:

Irreversible loss of gas exchange surface area
Inflammation beyond terminal bronchioles
Destruction of elastic connective tissue
Enlarged alveoli with fewer total alveoli
Difficulty exhaling

Causes:

Usually smoking
Rarely alpha-1 antitrypsin deficiency

Objective 52: Asthma

Symptoms:

Dyspnea
Wheezing
Chest tightness

The slides describe asthma as an immune response involving:

IL-4
IL-5
IgE
Airway inflammation that precedes bronchospasm

Medications Listed

Bronchodilators

Albuterol (Ventolin)
Ipratropium (Atrovent)
Albuterol + Ipratropium (Combivent, Duoneb)

Inhaled Steroids

Fluticasone (Flovent)
Budesonide + Formoterol (Symbicort)

22, Respiratory Vu (11 ed).ppt

Objective 53: Tuberculosis (TB)

Cause:

Mycobacterium tuberculosis

Symptoms:

Fever
Night sweats
Weight loss
Severe cough
Splitting headache

Treatment:

12-month course of antibiotics

22, Respiratory Vu (11 ed).ppt

Objective 54: Lung Cancer

Accounts for about one-third of cancer deaths in the United States.

According to the slides:

90% of patients were smokers.

Types

1. Squamous Cell Carcinoma

20–40%
Originates in bronchial epithelium

2. Adenocarcinoma

25–35%
Originates in the peripheral lung

3. Small Cell Carcinoma

20–25%
Originates in the primary bronchi
Metastasizes early

22, Respiratory Vu (11 ed).ppt

⭐ FINAL EXAM CRAM SHEET

Brainstem Respiratory Centers

DRG: Quiet inspiration
VRG: Forced breathing
PRG: Smooths breathing; inhibits inspiration

Four Factors Affecting Breathing

Pulmonary irritant reflex
Inflation (Hering–Breuer) reflex
Higher brain centers
Chemical factors

Chemoreceptors

Central: Respond to CO₂/H⁺
Peripheral: Respond mainly to low PO₂