Gas Exchabge Flashcards
How does your body adapt from aerobic excercise
None makes more red blood cells so more oxygen can be transported in the blood,
your arteries become wider and more elastic so that your blood pressure falls
Your heart grows bigger (hypertrophies) and the walls become thicker so that they can pump more blood with each beat. This means it doesn’t have to beat so fast.
More blood capillaries grow within your muscles so that more oxygen can get there more quickly
Your heart rate returns to normal more quickly following excercise
More blood capillaries also grow around the alveoli in your lungs so more oxygen is taken into the blood and more carbon dioxide is released .
Your diaphragm and intercostal muscles become stronger so they can make your chest cavity bigger meaning you can breathe in more air
How does excercise cause adaptations within your muscles bones , joints and energy systems
Your muscles grow lager and stronger
Your tendons grow bigger and stronger
Your body gets better at respiring fat , even when you aren’t excercise for
Your muscles get better at using oxygen
Your oxygen consumption rate increases
Ligaments and cartilage at your joints grow thicker and stronger
Bones become stronger
What happens when we breath in
Chest expands and the diaphragm contracts , increasing volume in the thorax and atmospheric pressure pushes air into the lungs
How is the thorax adapted
Two pleural membranes are internally lubricated and cause the chest movement to be frictionless
How does exhalation occur
External intercostal sand diaphragm relax and the chest contracts and the elastic recoil causes the pressure in the thorax to increase and forces air out of the lungs
How do we increase the rate of exhalation
During active breathing , as when we run , the internal intercostal muscles need to contract in order to increase the rate of exhalation which would otherwise be too low during vigorous exercise
How does gaseous exchange occur
Gas exchange will only occur so long as there is a concentration gradient of the gases in the appropriate directions .the heart continually replaced blood in contact with the alveoli with fresh deoxygenated blood , keeping the oxygen concentration low and the carbon dioxide concentration high on the capillary side of the respiratory membrane . The process of ventilation maintains the oxygen concentration high and the carbon dioxide concentration low on the alveolar side of the respiratory membrane .it the concentration of both gases were the Same no gas exchange would occur
What is asthma
A chronic inflammatory problem that causes the overproduction of mucas and reduction in diameters of smaller bronchi and bronichles in response to an allergen
What is bronchitis
An inflammatory response involving hyoertrophy of glands and goblet cells lining the bronchi. Atmospheric pollution may be a contributory factor , excessive mucus being produced as sputum. Chemicals in tar paralyse cilia and stimulate additional mucus production , mucus gravitates to the lungs , bacteria becomes trapped in the mucus and causes infection and irritation . Mucus blocks the airways and breathing is more difficult and gas exchange is reduced
How can cigarette smoking harm your lungs
It produces lots of inflammatory substances and is the major cause of chronic bronchitis , lasting from months to years . Nicotine in the smoke dissolves in the alveolar capillaries and then causes adrenaline to be secretes , raising cardiac output and blood pressure . Cigarette smoking also deactivates the enzyme anti trypsin which normally inhibits the proteases and elastases which would otherwise attack the alveoli
What is emphysema
Removal of soot by white cells and continuous coughing damages the alveoli. Alveolar walls disintegrate resulting in large air spaces which do not close during exhalation . Reduced surface area for gaseous exchange and loss of elasticity make exhalation very hard are effects. The major cause of this problem is long term irritation of the air passages as from cigarette smoking or air pollution
What is diffusion
Diffusion is the net passive movement of particles (atoms, ions or molecules) from a region in which they are in higher concentration to regions of lower concentration.
What is aerobic excercise
Submaximal excercise which gets your heart rate and breathing rate up over a sustained period , for example : jogging , swimming , cycling . If you perform aerobic excercise regularly your body adapts. It is excellent for the health of your heart and lung
How does diffusion occur in humans
In humans gases drawn into the lungs diffuse across the thin walls of the alveoli and the blood
What happens when we breathe
Air is moved into and out of our lungs , this involves different parts of the respiratory system inside the thorax.
When we breathe in , air enters through the nose and mouths in the nose the air is moistened and warmed .
The air travels down the trachea to the lungs , tiny hairs called cilia help to remove dirt and microorganisms.
The air enters the lungs through the bronchi which branch and divide to form bronichles.
At the end of the bronichles are air sacks . Alveoli are in the air sacs , the alveoli are covered in tiny blood capillaries where oxygen and carbon dioxide are exchanged
What surrounds the lungs
Pleural membranes . An inner one attached to the lung surface and an outer one attached to the thoracic wall and diaphragm. Between the membranes is a little fluid that helps them slide smoothly over each other.
What is outside the pleural membranes
The ribs , joined together by intercostal muscles, there are two sets of intercostal muscles : external and internal
What is below the lungs
The diaphragm , a large sheet of tough tendon tissue surrounded by muscle tissue that attaches to the thorax .
What do the pleural membranes , ribs , intercostal muscles and diaphragm do
Work together to allow breathing
What is ventilation
The way that oxygen is taken into our bodies and carbon dioxide removed
How are the changes in thorax volume caused
The diaphragm and intercostal muscles . In gentle breathing , only the diaphragm . I’n deep breathing such as during exercise the intercostal muscles and ribs become involved also
What happens during inhalation
1.the diaphragm contracts and flattens in shape
2.The external intercostal muscles contract making the ribs move upwards and outwards
3.these changes cause the volume of the thorax to increase
4.this causes air pressures to decrease 5. This decrease in pressure draws air into the lungs
Rings of cartilage in the trachea and bronchi keep air passages open and preven them from collapsing when air pressure decreases and bursting when pressure increased
What happens during exhalation
- The diaphragm relaxes and returns to its domed shape, pushed up by the liver and stomach. This means it pushes up on the lungs.
- The external intercostal muscles relax, allowing the Ribs to drop back down. This also presses on the lungs. If you are breathing hard internal intercostal muscles also contract, helping the Ribs to move down
- These changes cause the volume of the thorax to decrease , causing air pressure in the thorax to increase and air is then pushed out of the lungs
What happens to other gases in the air we breathe in
Oxygen is diffused into the blood and all other gases are breathed out almost unchanged
