Bio Ch 35 Flashcards
(40 cards)
Respiration
sequence of events that results in gas exchange between the body’s cells and the environment
Ventilation
breathing; includes inspiration (entrance of air into the lungs) and expiration (exit of air from the lungs)
External respiration
gas exchange between the air and the blood within the lungs; blood then transports oxygen from the lungs to the tissues
Internal respiration
gas exchange between the blood and the tissue fluid; blood then transports carbon dioxide to the lungs
Gills
finely divided, vascularized outgrowths of the body surface or the pharynx
Tracheae
insects have a system of air tubes called this through which oxygen is delivered directly to the cells without entering the blood
Lungs
terrestrial vertebrates usually have these, which are vascularized outgrowths from the lower pharyngeal region
Countercurrent exchange
fish use this to transfer oxygen from the surrounding water into their blood
Pharynx
air and food passages in humans cross in this; advantage = letting you breathe through your mouth in case your nose is plugged up; also permits greater intake of air during heavy exercise, when greater gas exchange is required
Glottis
air passes from the pharynx through this, which is an opening into the larynx
Larynx
voice box
Vocal cords
at the edges of the glottis are two folds of connective tissue covered by mucous membrane, called these; flexible and pliable bands that vibrate against each other, producing sound when air is expelled past them through the glottis from the larynx
Trachea
windpipe; held open by a series of C-shaped, cartilaginous rings that do not completely meet in the rear
Epiglottis
when food is being swallowed, the larynx rises, and the glottis is covered by a flap of tissue called this
Bronchi
trachea divides into 2 primary ____, which enter the right and left lungs
Bronchioles
branching continues from the bronchi, eventually forming a great number of smaller passages called this
Alveoli
each bronchiole terminates in an elongated space enclosed by a multitude of air pockets, or sacs, called this, which fill the internal region of the lungs; internal gas exchange occurs between the air in these and the blood in the capillaries
Inspiration
inhalation; act of moving air into the lungs
Expiration
exhalation; act of moving air out of the lungs
Diaphragm
horizontal muscle that divides the thoracic cavity (above) from the abdominal cavity (below)
Tidal ventilation mechanism
all terrestrial vertebrates except birds use this, so called because the air moves in and out by the same route
One-way ventilation mechanism
birds use this method of breathing; incoming air is carried past the lungs by a trachea, which takes it to a set of posterior air sacs; air then passes forward through the lungs into a set of anterior air sacs; from here it is expelled; fresh air never mixes with used air in the lungs, thereby greatly improving gas-exchange efficiency
Respiratory center
rhythm of ventilation is controlled by this in the medulla oblongata of the brain; automatically sends out impulses by way of a spinal nerve to the diaphragm (phrenic nerve) and intercostal nerves to the intercostal muscles of the rib cage (inspiration occurs); when this stops sending neural signals, expiration occurs
Carotid bodies
structure located at the branching of the carotid arteries; contains chemoreceptors sensitive to the O2, CO2, and H+ content in blood