Diffusion (of anything) occurs because of a concentration gradient meaning there is more oxygen in one place than another.
Alveolus when you inhale will have a higher concentration of oxygen that that of the alveolar capillary resulting in a concentration gradient, this causing diffusion to occur until equilibrium is met.
This means more oxygen in alveolus so oxygen travels into the alveolar capillary until a balanced amount of oxygen is in both places, but then of course the oxygen is transported and you exhale and inhale so the process repeats.
Before diffusion there is a higher concentration of oxygen molecules outside the cell than inside the cell. After diffusion the concentration of oxygen molecules is the same outside and inside the cell.
Yes it is.
Diffusion along the (partial) pressure gradient.
It defuses throught the respiratory membrane and binds to hemoglobin (in humans) following a hemoglobin type-specific binding affinity curve (depending on the Po2 of the local atmosphere.)
a capillary is our body's smallest form of blood vessel the more capillary's at the muscles, the more oxygen the muscles can use an increase in capillarisation means that there is an increase in blood vessels and subsequently an increase in the opportunity for blood (and oxygen) to be transported to and used by the muscles a decrease in capillarisation means that there is a decrease in poo vessels and subsequently a decrease in the opportunity for blood (and oxygen) to be transported to and used by the muscles aerobic or endurance training does well to bring about an increase in capillarisation, meaning that muscles can perform for longer peroids of time as they are able to use more oxygen for contraction
Emphysema. The alveolar walls are destroyed and replaced with scar tissue, which cannot allow diffusion of oxygen from the alveolus to the capillary. It cannot be reversed.
Simple diffusion
Oxygen is transferred to hemoglobin at the alveolar/capillary function. This transfer occurs through diffusion.
Oxygen.
Around the lungs,the blood is separated from the air inside each alveolus by only two cell layers; the cells making up the wall of the alveolus and the capillary wall itself. This is a distance of less than a thousandth of a millimetre. Because the air in the alveolus has a higer concentration of oxygen than the blood entering the capillary network, oxygen diffuses from the air across the wall of the alveolus and into the blood. That is why the distance is important.
In the alveoli
It will be absorbed from the air into your lungs. Then when it reachs the alveolus it will diffuse from the alveolus into the blood capillaries down an oxygen concentration through diffusion where it will combine with the heamoglobin in the Red Blood Cells.
Oxygen diffuses into the blood capillary
Oxygen and carbon dioxide travel into and out of the bloodstream via diffusion across alveolar and capillary membranes.
Within the lungs.
diffusion
The alveolus is a air sac that holds the oxygen. It squashes the oxygen molecules so they diffuse from the alveolus into the capillary. From there, they attach themselves to deoxygenated Red Blood Cells. The oxygen in the blood plasma are also squashed and are diffused. They go from the capillary to the alveoli to get breathed out. The alveoli transfers the oxygen to the lung capillaries and oxygenates the blood, then it is breathed out as Carbon Dioxide.