Q.11 What do you know about Nicotine? Answer: Nicotine is a powerful poison and was widely used as an insecticide in the past. When inhaled through tobacco smoking, it reaches our circulatory system and not only hardens the walls of the arteries but also damages the brain tissues.
Q.9 Describe different types of respiratory disorders in man. Q.9 Describe different types of respiratory disorders in man. Answer: There are a number of respiratory disorders which affect people. The high percentage of respiratory disorders in Pakistan is due to more concentration of air pollutants both in urban and rural atmosphere. Some of the important …
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Q.8 Describe the comparison between the inspired and the expired air. Answer:
Q.7 Describe the mechanism of breathing Answer: The physical movements associated with the gaseous exchange are called breathing. Phases of Breathing There are two phases of breathing i.e. 1. Inhalation 2. Exhalation 1. Inhalation or inspiration a) Contraction of rib muscles and diaphragm During inspiration the rib muscles contract and ribs are raised. At the …
Q.6 Describe the structure and functions of human respiratory system Answer: Introduction In humans and other higher animals, the exchange of gases is carried out by the respiratory system. We can divide respiratory system in two parts i.e. (1)The air passageway (2)The lungs 1. Air passageway Definition It consists of the parts through which the …
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Q.5 Describe the process of gaseous exchange in plants. Answer: Introduction Plants have no organs or systems for the exchange of gases with the environment. Every cell of a plant exchanges gases with the environment by its own. Explanation i) Gaseous exchange in leaves and young stems The leaves and young stems have stomata in their …
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Q.4 What is breathing? How is it different from respiration? Answer: Breathing The process through which animals take air in their bodies to get oxygen from it and then give out the air for getting rid of carbon dioxide. Difference between respiration and breathing. RESPIRATION (i) It involves the mechanical and the bio-chemical processes. (ii) It is …
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Q.3 Define gaseous exchange. Why oxygen is needed? Answer: Cellular respiration is the process in which the C-H bonds in food are broken by oxidation reduction reactions and energy is transformed into ATP.