gas ex Flashcards
6 factors influencing gas exchange
respiratory surface or organ
Respiratory system relies on the diffusion of gases down pressure gradient.
Surface-to-volume ratio
Ventilation
Perfusion
Respiratory Pigments or Proteins
part of an animal’s body where gases are exchanged with the environment.
respiratory surface or organ
allow the gas exchange, it must be moist, large enough, and protected from dedication.
respiratory surface or organ
Partial pressures for gas in the atmosphere can be computed.
Respiratory system relies on the diffusion of gases down pressure gradient.
partial pressure of oxygen in alveolar air is about
104 mm Hg
partial pressure of oxygenated pulmonary venous blood is about
100 mm Hg
states that the amount of diffusion of a gas across a membrane is proportional to the surface area and the difference in partial pressure between two sides and inversely proportional to the thickness of the membrane.
Frick’s Law
s, the surface area increases at a lesser rate than its volume, making diffusion of gases into the interior more difficult.
Surface-to-volume ratio
a body design that keeps the internal cells close to the surface
Surface-to-volume ratio
refers to the movement of the respiratory medium (air or water) over the respiratory surface.
Ventilation
refers to the flow of blood to alveolar capillaries.
Perfusion
volumes involved in ventilation and perfusion should be compatible.
Perfusion
Adaptations of animals for gas exchange include respiratory pigments that bind and transport gases.
Respiratory Pigments or Proteins
3 the respiratory surfaces or organs in invertebrates
Integumentary exchange
External gills-
Tracheal system in arthropods
3 the respiratory surfaces or organs in vertebrates
External gills-
Internal gills-
Lungs-
nternal respiratory surfaces shaped as a cavity or sac
Lungs
provided a membrane for gaseous exchange.
Lungs
rows of slits or pockets in adults fishes positioned at the back of the mouth such that water that enters the mouth can flow over them as it exits just behind the head.
Internal gills
thin, vascular projections from the body surface of a few amphibians.
External gills
- refers to the general body surface or skin used by animals with high surface-to-volume ratio;
Integumentary exchange-
used by invertebrates that live in aquatic habitats;
External gills
gills are highly folded, thin-walled, vascualarized epidermis that project outward from the body
External gills-
utilizes fine air-conditioning tubules to provide gaseous exchange at the cellular level. It is not dependent on a circulatory system;
Tracheal system in arthropods
Water flows over the gills and blood circulates through them in opposite direction. This mechanism, called
countercurrent flow
is much more efficient than co-current exchange.
Countercurrent
controls oxygen and carbon dioxide levels for the entire body by regulating the rate and depth of breathing.
nervous system
the muscles around bronchioles contract more than usual, increasing resistance to airflow.
asthma
abnormal condition of the lungs marked by decreased respiratory function. It is associated with smoking or chronic bronchitis or old age.
Emphysema
is an infectious disease involving inflammation and fluid buildup in the lungs.
Pneumonia
conduct substances such as products of photosynthesis, water, and other compounds.
Phloem cells
can be explained by both “push” from below and “pull” from above.
xylem
describes the movement of substances in the phloem from source cells to sink cells.
Pressure flow or bulk flow
do not have a circulatory system.
sponges, cnidarians, and flatworms,
rely on water flow through their bodies for obtaining food, oxygen, and removing waste.
Sponges
have direct contact of cells with water for oxygen, nutrient, and waste exchange.
Cnidarians
being small and flat, can diffuse oxygen through their skin and do not require a circulatory system.
Flatworms,
Vertebrates, including humans, have a circulatory system.
closed circulatory system.
collect blood from veins
Atria
pump blood into arteries.
ventricles
prevent backflow of blood between chambers.
Valves
a connective tissue consisting of plasma, red blood cells, white blood cells, and platelets.
Blood
Blood vessels include;
arteries, arterioles, capillaries, venules, and veins.
carry oxygenated blood except for the pulmonary artery,
Arteries
carries deoxygenated blood.
pulmonary artery
return deoxygenated blood back to the heart.
Veins
systems use hemolymph and have a central body cavity (hemocoel) for nutrient and gas exchange.
Open circulatory
have blood enclosed within vessels and are more efficient.
- Pulmonary circulation moves blood to and from the lungs for oxygenation.
Closed circulatory system
moves blood to and from the lungs for oxygenation.
Pulmonary circulation
provides oxygen and nutrients to body tissues and removes waste products.
Systemic circulation
supplies oxygenated blood to the heart muscle.
Coronary circulation
