9. Respiration And Regulation Of The Internal Environment Flashcards
What is partial pressure?
A measure of the force exerted by the individual components in a mixture of gases.
What is total pressure?
The sum of all partial pressures of all the gases in a mixture.
What is atmospheric pressure?
The pressure exerted by the weight of the atmosphere.
What is the mean atmospheric pressure at sea level?
760 mm Hg.
101.3 kPa
What is the partial pressure equation of atmospheric oxygen?
Pressure oxygen = total pressure X % Oxygen
Is partial pressure the same as concentration?
No.
When a liquid is exposed to air, what is the difference in partial pressure of a gas present in both the liquid and air?
It is the same because an equilibrium state is reached.
What is the difference in oxygen solubility in water vs air?
Oxygen is less soluble in water than it is in air.
Why is getting oxygen from water harder than getting it from air?
Water is more dense and has a higher viscosity than air.
Respiratory surfaces are always…?
Moist.
What are 2 characteristics of respiratory surfaces?
- Large.
- Thin.
Diffusion is faster with a large surface area and a short path to travel
What are gills?
Branching organs with a high surface area, dense with capillaries, that are suspended in water for gas exchange.
What is ventilation?
The process of the respiratory medium moving over the respiratory surface.
Ventilation maintains the partial pressure gradients of oxygen and carbon dioxide.
Why do fish need to maximise their oxygen uptake?
There is a lower concentration of oxygen in water.
Where do fish uptake water?
Fish take water in through their mouth and pass it over their gills.
What is countercurrent exchange in fish?
In fish capillaries, blood and water flow in opposite directions, which drives net oxygen diffusion from the water into the blood.
What is the enclosed respiratory system of an insect called?
The tracheal system.
What is the tracheal system?
A network of tubes throughout an insect’s body, with air sacs located near organs that need oxygen and spiracles in the tracheal branches.
What are spiracles?
External openings that allow air to flow in and out of a system.
What is the simplified process of respiration in an insect’s body?
- Air enters through spiracles (external openings).
- Air moves to trachea and through tracheal branches, bringing oxygen within a short distance of all cells.
- Gas diffusion occurs through the moist epithelial lining at the end of the branches.
- Carbon dioxide leaves the body through the spiracles.
Can insects regulate the amount of air that moves through their tracheal system?
Yes.
But it is complicated.
What are lungs?
Specialised internal respiratory organs that are not in direct contact with the rest of the body, requiring transport of gases from unreachable cells via the circulatory system.
What type of circulatory system has lungs?
Both closed and open circulatory systems.
What is a cloaca?
An opening at an animal’s posterior where the digestive, reproduction, and urinary tracts meet.
Found in reptiles, avians and some other vertebrates
Turtles can supplement lung breathing with gas exchange known as…?
Cloacal breathing.
What is the larynx?
The voice box.
Vocal chords are located in the upper larynx.
Where is the larynx?
The upper part of the respiratory tract.
Before the trachea and after the pharynx.
What is the pharynx?
A muscular tube consisting of the nasopharynx, oropharynx, and laryngopharynx.
Where is the pharynx?
The upper respiratory tract.
At the junction where food and air cross, above the larynx.
What is the epiglottis?
A small moveable flap just above the larynx that prevents food and drink from entering the trachea.
What is the trachea?
A single tube that connects the larynx to the bronchi.
Also known as the windpipe.
What are the bronchi?
A pair of pipes that branch from the trachea to the lungs.
bronchus = singlular
What are the bronchioles?
The finer branches of the bronchi that transport air to and from the alveoli.
What are the alveoli?
Air sacs at the end of a bronchiole where gas exchange occurs.
alveolus = singular
What are 3 anatomic characteristics of alveoli?
- Very thin walls.
- Dense covering of capillaries to support gas exchange.
- Lined with surfactant.
What is surfactant?
A surface-agent secreted by alveoli that decreases surface tension, preventing alveoli collapse.
What is choking?
Breathing difficulties resulting from acute obstruction of the airways.
What is the diaphragm?
A sheet of muscle that forms the bottom wall of the thoracic cavity in mammals.
What are 8 anatomic features passed through in respiration?
- Nasal cavity.
- Pharynx.
- Epiglottis.
- Passes larynx.
- Trachea.
- Bronchi.
- Bronchioles.
- Alveoli air sacs.
What is the function of the nasal cavity?
It fillters, warms and humidifies the air.
How many lobes does the human right lung have?
3 lobes.
Upper, middle and lower.
How many lobes does the human left lung have?
2 lobes.
Upper and lower.
Why do humans have a different number of lobes on the left and right lungs?
The left lung has to accommodate the heart.
What are the 4 structures that air goes through from the bronchioles to the air sacs?
- Terminal bronchioles.
- Respiratory bronchioles.
- Alveoli ducts.
- Alveoli sacs.
Where does deoxygenated blood enter the alveoli from?
The pulmonary artery.
Where does oxygenated blood leave the alveoli from?
The pulmonary vein.
How many spherical alveoli are in alveolar sacs?
20 to 30
What is breathing?
The process of ventilating the lungs through an alternation between inhalation and exhalation of air.
What mechanism of breathing occurs in birds?
Two cycle breathing.
What mechanism of breathing occurs in amphibians?
Positive pressure breathing.