Breathing is an involuntary action because it is controlled by the brain.
When humans respire anaerobically, this produces lactic acid.
Birds have lungs with air sacs. The air sacs make the body of the bird light in weight. This is an adaptation that helps birds fly.
Gaseous exchange takes place through moist skin. The entire body surfers as the respiratory organ.
When we are bored, tired or hungry, there is a lack of oxygen level inside our body. So yawning helps us to bring more oxygen into our blood and move more carbon dioxide out of the blood.
Respiration through the lungs is known as pulmonary respiration and respiration through the skin is known as cutaneous respiration.
The hair and mucus present in the nostrils trap dust and germs present in the air. Trachea too contains mucus which traps dust and microorganisms that have managed to pass through the nostrils which prevents dust particles from entering into lungs.
When muscles fail to receive enough oxygen, they respire anaerobically for a short period of time. This produces lactic acid and the person developed cramps temporarily and is forced to rest for a while.
The root hairs have tiny pores open for respiration. If we over-watered the plant, the spaces between the soil particles are occupied by water. So the roots do not get oxygen from the air spaces and the plant will die.
As the blood flows through the body, carbon dioxide formed during respiration passes into the blood and binds to the red blood cells.
This blood reaches the heart, which sends the blood to the lungs.
In the lungs, Carbon dioxide detaches from the red blood cells and enters the air sacs. Carbon dioxide is removed from the lungs when you breathe out.
When climbing mountains, the amount of oxygen in the air decreases (due to low air pressure). So, the mountaineers feel dizziness. To avoid such problems mountaineers carry oxygen cylinders with them.
Taking in oxygen and given out carbon dioxide is external respiration also called breathing.
Carrying oxygen to the cells and carbon dioxide out of the cell through blood is called internal respiration.
Breaking down of food/glucose within the cell in the presence of oxygen to release energy is called cellular respiration.
The RBCs contain a protein called hemoglobin which binds with oxygen and forms a compound called oxyhaemoglobin. Oxyhaemoglobin is carried through the blood to all the cells of the body. In the cells, oxygen is released from oxyhaemoglobin. Cells use this oxygen to breakdown glucose (sugar) to form carbon dioxide and water.
(a)In Cockroaches, exchange of gases occurs through small openings or pores called spiracles present on the sides of their body.
(b) network of these pores is connected with air tubes called trachea, which carries oxygen to different parts of the body.
(c)Carbon dioxide diffuses out to the trachea and exits through the spiracles.
