Human+Respiration


 * Drowning

> Human can die from drowning ** > What is the cause of death? : Water enters the lungs. - too little oxygen in the water, too much water, can't undergo ventilation

Why are muscles red? Because of the myoglobin in the muscles. (e.g. chicken thighs) Haemoglobin When we are running, oxygen is taken from the myoglobin, not waited for the oxygen to be transported there.

Over time, as the oxygen produced lessens, the lactic acid will build up. The production will lessen and lessen until the person either faints (the face turns pale because all blood is taken from the face/head to the legs—to allow one to run more with more oxygen) or spasms. When one stops, they pant, to get more oxygen, and get rid of the lactic acid. The lactic acid cannot be converted to anything. They have to go to the liver and be converted to carbon dioxide and water, because lactic acid is deemed as 'poisonous' in the body. An accumulation of lactic acid in the body is bad for the body.

Tracheal contains fluid. The cockroaches have oxygen-riched water in the lungs and let the oxygen diffuse in the body.
 * Why don't cockroaches drown?!?!?!

**Gas Exchange The process by which oxygen is acquired and carbon dioxide is removed. Cellular respiration creates a constant demand for oxygen and a need to eliminate carbon dioxide gas.

Lungs: moisture must dissolve before the air can be used by the body. To stay alive underwater longer: lungs must contain oxygenated water, instead of air.

We don't breathe in water. We breathe in air. The lungs use diffusion to move the oxygen into the carbon dioxide.

Is our air only carbon dioxide and oxygen? Nah. There is also nitrogen. Do we have dissolved nitrogens in the body? Logically, yes. But. We don't have them. Because oxygen bond with the haemoglobin, but nothing binds to nitrogen. The body doesn't want it, so it diffuses out (from fluid first, then become gaseous)

Diffusion is the universal transfer. Osmosis is only for water ^^

Divers: if they surface quickly without depressurizing, they would suffer diver's bent. The joints cannot bend. Big fat air bubbles going through the tiny capillaries would give it too much pressure and causing it to burst.

1. Large surface area: volume ratio 2. Thin membrane 3. Moisture (oxygen has to dissolve in moisture before going into the body.) 4. Efficient Transport system (circulatory system) so as to establish a concentration gradient (the haemoglobin with oxygen must quickly move away: take oxygen and remove: so that the transport system is efficient.) 5. Ventilation (when you breathe, you're actually ventilating the space (chest area): our body only has one opening, so there must be a ventilating system that allows the air to go in and out)
 * Properties of Gas Exchange Surfaces:

Ribs: Intercostal muscles: the ribs move by one, joined by the intercostal muscle Middle of ribcage: sternum CPR: press the sternum because it is cartilage and is elastic. The end of the sternum is a flap that is flexible. Muscles are in bunches (bunched up by a membrane) so as to be able to move more easily. Individual muscles do not have enough strength to move on its own. We are not symmetrical because the heart is on the left side. The left sided lung have one less lobe than the one on the right to make space for the heart -.-"

We must move when we sleep: muscles contract and relax, else it would have lactic acid buildup. Trachea must always be maintained as a tube to allow easy breathing (like a straw. A flat straw cannot take in water easily). If it is a tube, the tube next to it (esophagus). The trachea has c-shaped cartilage around it to hold it in place? To hold is as a tube. However, not the entire trachea is cartilaged so that the esophagus can expand when the bolus of food goes down. If not, the esophagus cannot expand. Also, if the esophagus is cartilaged, food will just zoom down.

Increase the thoracic value, and the air will go in to balance out the pressure. Decrease, and the air goes out. Increase in volume cause a decrease in pressure in the lungs, causing the air to rush in to balance the pressure. And vice versa. Pressure = inverse of volume

Air is filtered by cilia, moistened by mucus membrane, and warmed by the blood. The larynx/voice box contains the vocal cord?

Haemoglobin with oxygen: red Without oxygen: purplish Give out oxygen as they travel through vessels

Interesting phenomenon about haemoglobin: In order to make sure that the oxygen from the atmosphere is dissolved and quickly transported away, haemoglobin quickly takes it and carries it away to maintain the concentration gradient. When the red blood cells goes to the muscles, the haemoglobin gives the oxygen away to the muscles

partial pressure

carbon dioxide form carbonic acid (pH of blood is slightly acidic because there is always dissolved co2—carbonic acid) in the blood. They will need an enzyme to get rid of it. Co2 is converted into carbonic acid so that it can be carried away faster by the plasma

High pH, high CO2: body believes that you are working and needs more ATP. When the pH goes up (the carbonic acid gathers), the brain (all blood go through the brain) realizes that the pH is abnormal, and the lungs should relax and contract more (people start panting) The control of breathing is controlled by the presence of co2 rather than the absence of o2. There is no way the body can detect too much/too little oxygen, but it can detect the amount of co2 due to the amount of acid in the blood.

Is dissolving carbon dioxide in the plasma the only way to lower the pH? In your diet, because of other mechanism, the pH changes and is lowered. The body will think that there is not enough oxygen, causing the body to breathe more. Some medicine also has the same effect. When you are conscious of your breathing, it shows that something is wrong. Breathing should be subconscious.

Carbon monoxide has the same property as oxygen, and form a more permanent bond with the haemoglobin, refusing to let go despite drop in pressure. More and more haemoglobin are bound by carbon monoxide. ** People feel sleepy due to carbon monoxide poisoning—lack of oxygen. People falls asleep, and the oxygen level drops and they die. **
 * Carbon Monoxide