ATI TEAS Respiratory System

Respiratory system

Organ system that brings oxygen into the body and removes carbon dioxide

What is the main function of the respiratory system?

To exchange oxygen and carbon dioxide between the air and blood

Alveoli

Tiny thin-walled air sacs where gas exchange occurs

Why are alveoli effective for gas exchange?

They have thin walls and large surface area, allowing rapid diffusion

Ventilation

Movement of air into and out of the lungs

What is the difference between ventilation and gas exchange?

Ventilation moves air, while gas exchange swaps oxygen and carbon dioxide

Trachea

Tube reinforced with cartilage that carries air to the bronchi

Why does the trachea have cartilage rings?

To prevent collapse and keep the airway open

Bronchi

Main branches from the trachea that lead into each lung

Bronchioles

Smaller airways that branch from bronchi and lead to alveoli

What structure directly connects to alveoli?

Bronchioles

Surfactant

Substance that reduces surface tension in alveoli

Why is surfactant important?

It prevents alveoli from collapsing

Right lung

Lung with three lobes

Left lung

Lung with two lobes

Why is the left lung smaller than the right lung?

To make room for the heart

Mediastinum

Space between the lungs where the heart is located

Pleura

Double membrane surrounding the lungs

What is the function of pleural fluid?

Reduces friction between lungs and chest wall

Capillaries

Tiny blood vessels where gas exchange occurs

How do the respiratory and cardiovascular systems work together?

Lungs oxygenate blood, and the heart transports it throughout the body

Diffusion

Movement of molecules from high to low concentration

What drives gas exchange in the lungs?

Concentration gradients of oxygen and carbon dioxide

In which direction does oxygen move during gas exchange?

From alveoli into blood

In which direction does carbon dioxide move?

From blood into alveoli

Why is the alveolar wall thin?

To decrease diffusion distance and increase efficiency

Diaphragm

Muscle that controls breathing by changing lung volume

What happens when the diaphragm contracts?

Lung volume increases and air flows in

What happens when the diaphragm relaxes?

Lung volume decreases and air flows out

Intercostal muscles

Muscles between ribs that assist with breathing

What causes air to move into the lungs?

Decreased pressure inside the lungs

What causes air to move out of the lungs?

Increased pressure inside the lungs

Tidal volume

Amount of air inhaled or exhaled during normal breathing

Residual volume

Air remaining in lungs after exhalation

Why does residual volume exist?

To prevent lung collapse and maintain gas exchange

Medulla oblongata

Brain region that controls breathing

What triggers an increase in breathing rate?

Increased carbon dioxide or decreased blood pH

Asthma

Condition where airways narrow due to inflammation or mucus

What happens to airflow during asthma?

Airflow is restricted, making breathing difficult

Inflammation

Swelling that narrows airways and reduces airflow

How do pollutants affect the respiratory system?

They damage airways, reduce function, and trigger inflammation

Cystic fibrosis

Genetic disorder causing thick mucus buildup in lungs

How does cystic fibrosis affect breathing?

Mucus blocks airways and reduces gas exchange

Influenza

Viral infection that affects the respiratory system

How does influenza affect the body?

It infects respiratory cells and triggers immune response causing symptoms

What determines the rate of diffusion in the lungs?

Surface area, concentration gradient, and thickness of membrane

Why is large surface area important in lungs?

It increases the rate of gas exchange

What happens if alveoli walls become thick?

Gas exchange slows down

What is pulmonary circulation?

Movement of blood from heart to lungs and back

What is systemic circulation?

Movement of oxygenated blood from heart to body

What happens to blood after it leaves the lungs?

It becomes oxygenated and returns to the heart

How does breathing help maintain blood pH?

By regulating carbon dioxide levels