What role does hair present in nasal cavity play in the process of respiration?
Answer
Air around us contains various unwanted particles like smoke, dust, pollens, etc. during inhalation of air these particles get trapped in the hair of nasal cavity and thus these hairs allow clean air to enter our body.
In water, frogs exchange gases through its thin, moist and smooth skin which is richly supplied with blood capillaries. On land, frogs breathe through lungs.
When breathe is released after holding it for few minutes. What happens and give reason for its occurrence?
Answer
Releasing breathe after holding it for sometime results in rapid breathing. It occurs to maintain a healthy balance between intake of $O_2$ and release of carbon dioxide.
Write the difference in the composition of inhaled and exhaled air.
Answer
The inhaled air has larger concentration of oxygen and lesser concentration of carbon dioxide, whereas exhaled air has larger concentration of carbon dioxide and lesser amount of oxygen.
Fish respire through their gills. Dissolved air in the water is taken in by the gills and is supplied to blood capillaries where exchange of gases takes place.
Pick the odd-one-out from each of the groups given below on the basis of respiratory organs. Give reason for your answer. cockroach, grasshopper, snail, ant.
Answer
Snail is the odd one, as it does not breathe by means of tracheae.
Thin and moist skin helps frog in breathing. Because of thin skin, gases can diffuse (or exchange through) easily. Moist surface also helps gases to dissolve and diffuse into and out of skin cells.
In plants each part can independently take in oxygen from air and give out carbon dioxide. Leaves of the plants have tiny pores called 'stomata' for exchange of oxygen and carbon dioxide. Roots take up air from the pores (air spaces) present between the soil particles.
Water animals have gills that help them to use oxygen dissolved in water. Gills are projections of the skin which are well supplied with blood vessels for exchange of gases.
A food stall owner was preparing dough for making bhaturas. He added a pinch of yeast and sugar to the dough and left it in a warm place. After few hours, the dough had risen. There was a sour smell too. Why did the dough smell sour?
Answer
Yeast, during anaerobic respiration also produces alcohol which results in the sour smell of dough.
On a very cold morning, Boojho and Paheli were talking with each other as they walked down to their school. They observed that the air coming out of their mouth looked like smoke. They were asumed and wondered how it happened. Help them to find the answer.
Answer
On a cold day, the warm and moist air exhaled by us condenses into moist when it comes in contact with the cold air of the atmosphere, this looks like white smoke.
Why should you breathe through your nose and not your mouth?
Answer
When we breathe through the nose, the dust particles, smoke, etc. get stuck in the hair present in the nose, which act as filters. But if we breathe through the mouth, all the dust will enter our body system.
All organisms breathe in $\mathrm{O}_2$ and $\mathrm{CO}_2$. Should be less $\mathrm{O}_2$ and excess of $\mathrm{CO}_2$ in our environment.
Answer
The $\mathrm{CO}_2$ released by us is used by plants during the process of respiration and they release $\mathrm{O}_2$ as a result of this process which is used by rest of the organisms.
Insects have several small openings called spiracles on the lateral sides of their bodies. These spiracles lead to air tubes called trachea. Exchange of gases takes place through spiracles into trachea.
During aerobic respiration, carbon dioxide and water are released along with a large amount of energy. $\text{Glucose}\xrightarrow{\text{O}_2}\text{CO}_2+\text{Water}+\text{Energy}$