BIO 102-Chapter 30: The Respiratory System

the three characteristics of a respiratory surface

(1) Its surface area must be relatively large, (2) it must come into contact with either air or water, (3) it must consist of moist membranes across which O2 and CO2 diffuse.

larynx

A boxlike structure, located just below and in front of the pharynx, that produces the voice. It also directs ingested food and drink away from the respiratory system. AKA the Adam's apple.

epiglottis

A cartilage flap that covers the glottis during swallowing so that food enters the digestive tract instead of the lungs.

blood

A connective tissue consisting of cells and platelets suspended in plasma.

tidal volume

A measure of lung capacity by the amount of air inhaled or exhaled during a quiet breath taken at rest.

vital capacity

A measure of lung capacity by the total amount of air that a person can exhale after taking the deepest possible breath.

countercurrent exchange

A mechanism found in the gills of bony fishes, in which two adjacent currents flow in opposite directions and exchange materials with each other.

pharynx

A passageway leading from the back of the nose and the mouth. AKA the throat.

gills

A respiratory surface found in fishes, amphibian larvae and many invertebrates. Gases are exchanged at blood vessels covered by a thin layer of epithelium.

tracheae

A respiratory surface found in many arthropods including insects. Gases enter these chitin-lined air tubes and diffuse directly into the cells; they do not enter capillaries first as in most other respiratory systems.

body respiratory surface

A respiratory surface found in many invertebrates and amphibians. Gases diffuse through the body's surface.

lungs

A respiratory surface found in terrestrial vertebrates that allows for two-way airflow.

respiratory cycle

A single cycle of inhalation and exhalation.

exhale

Air flowing out of the lungs.

inhale

Air moving into the lungs.

hemoglobin

An iron-containing protein in red blood cells that reversibly binds oxygen.

red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

external respiration

Gas exchange between an animal's body and its environment.

internal respiration

Gas exchange between tissue cells and the bloodstream.

glottis

Slit-like opening between vocal cords.

respiratory surface

The area of an animal's body where external respiration occurs.

plasma

The liquid component of blood.

respiratory system

The organ system that does the breathing.

nose

The part of the body that forms the external entrance to the nasal cavity. functions in breathing, immunity and the sense of smell.

capillaries

The tiniest of blood vessels.

vocal cords

Two elastic bands of tissue that are stretched over the larynx. They vibrate as air from the lungs passes through the glottis producing the sounds of speech.