Week One Flashcards
Partial pressure
Pressure due to each individual gas
At a fixed temperature and pressure a partial pressure of a gas is proportional
To its concentration
Henry’s law
Amount of gas dissolved in a solution is proportional to its partial pressure
Active contraction of the diagram causes
Increased volume and decreased pressure in the chest cavity, and air flows into lungs
Relaxation of the diaphragm
Decreases volume and increases pressure of chest cavity, so air flows out of lungs
During inhalation aveolar pressure must be less or greater then atmospheric
Lower
Gas exchange occurs at the
Alveoli
Dead space refers to what part of the lungs
Trachea, bronchi, bronchioles
Volume of fresh air that reaches the alveoli is calculated as
Tidal volume - dead space volume
Partial pressure of oxygen decreases as
Rate of depth under water does
The atrium has —- walls whereas the ventricle has —- walls
Thin, thick
Describe steps of pulmonary circulation
- Blood returns to heart from body, and enters right atrium
- Blood then enters right ventricle
- Blood is then pumped from right ventricle to lungs
Describe steps of systemic circulation
- Blood returns to left atrium from the lungs
- Blood enters left ventricle
- Blood is pumped from left ventricle to rest of body
Cardiac cells are connected by
Gap junctions that are called intercalated disks that allow electrical signals to travel from cell to cell
Impulse conduct steps
- Electrical signal arrives at SA node
- Electrical activity goes rapidly to AV node via internodal pathway
- Electrical signal will spread slowly across atria and conduction slows through AV node
- Electrical signal flows rapidly through ventricular conducting system to apex of heart
- Electrical signal spreads upwards from apex
Why is it important that blood moves slowly through capillaries
It allows time for substances to be exchanged
