Question : (a)Write the reaction that occurs when glucose breaks down anaerobically in yeast.(b)Write the mechanism by which fishes breath in water.(c)Name the balloon likes structures present in lungs. List its two functions.(d)Name the respiratory pigment and writeits role in human beings.

Question : (a)Write the reaction that occurs when glucose breaks down

1.	Question : (a)Write the reaction that occurs when glucose breaks down anaerobically in yeast.(b)Write the mechanism by which fishes breath in water.(c)Name the balloon likes structures present in lungs. List its two functions.(d)Name the respiratory pigment and writeits role in human beings.
Answer» Solution :(a) Glucose BREAKS down anaerobically, i.e., in absence of `O_(2)`, in yeast in thefollowing manner : Glucose ` overset("In Cytoplasm")to "Pyruvate" overset(" In Cytoplasm, In absence of "O_(2))to "Ethanel" + CO_(2) +` Energy (b) Since fishes are aquatic, they take in `O_(2)` dissolved in water. They take water through theirmouth which goes to theirgills where the dissolved oxygen is taken up by the blood and transported. The `CO_(2)`is given out through the same passage. (C) The balloon like structures in our lungs are the alveoli. Their functions are : (i) They are very thin walled and hence help in gaseous exchange. (ii)They contain extensive network of blood vessels which help in TRANSPORT of respiratory gases. (iii)They INCREASE the surface area for absorption of gases. (d)Therespiratory pigment is haemoglobin. Its role is :(i)It has affinity for oxygen and hence helps in transport of oxygen form alveoli to body tissues. (ii)It also has affinity for `CO_(2)` and hence helps in transport of `CO_(2)`from body tissues to alveoli .