Biology 20 – Unit D Respiratory System

These flashcards cover key vocabulary and concepts related to the respiratory system, including definitions and functions of various components involved in breathing and gas exchange.

Breathing Movement

Controlled by the brainstem, specifically related to carbon dioxide and oxygen chemoreceptors.

Carbon Dioxide Chemoreceptor

Located in the medulla oblongata, sensitive to levels of carbon dioxide in the blood; activates breathing when CO2 levels rise.

Oxygen Chemoreceptor

Located in the carotid artery and aortic arch; signals the body to breathe when oxygen levels are low, serving as a backup system.

Negative Feedback Loop

A mechanism that regulates breathing by responding to changes in blood gas concentrations.

Carbon Monoxide

A dangerous gas that enters the bloodstream, preventing oxygen from binding to hemoglobin.

Breathing Rate (BR)

The speed at which an individual breathes, influenced by levels of carbon dioxide and oxygen in the blood.

Ventilation of the Alveoli

Increases significantly during heavy exercise to meet the demand for oxygen and carbon dioxide removal.

Hemoglobin

A protein in red blood cells that carries oxygen and can also buffer blood pH.

Gas Exchange

The process of breathing, transporting gases, and exchanging them at the cellular level in tissues.

Mucus

A sticky substance produced by cilia in the trachea that traps debris to help clean the air.

Larynx

The voice box composed of vocal cords; produces sound when air passes through.

Alveoli

Tiny air sacs where gas exchange occurs, connecting to a capillary network.

Intercostal Muscles

Muscles located between the ribs that aid in the breathing process.

Inhalation

The process of taking air into the lungs, expanding the chest cavity and lowering pressure.

Exhalation

The process of expelling air from the lungs, compressing the chest cavity and increasing pressure.

Carbonic Acid

Formed when carbon dioxide dissolves in the plasma; plays a role in maintaining blood pH.