Grade 5 Q&A: Chapter 21: Busy at Work - Our Internal Organs

Concept Questions

Q1: What is respiration?

Answer: Respiration is the process by which our body continuously takes in oxygen from the air through breathing, using organs like the lungs.

Q2: What are cilia and mucous in the respiratory system, and what is their function?

Answer: Cilia are fine hair-like structures on the inner lining of the respiratory organs, and mucous is a sticky substance also on this lining. Their function is to trap dust, smoke particles, and disease-producing micro-organisms, preventing them from reaching the lungs.

Q3: Name the main organs of the respiratory system.

Answer: The main organs of the respiratory system are the nose, trachea (windpipe), lungs, and diaphragm.

Q4: What is the diaphragm and how does it help in breathing?

Answer: The diaphragm is an organ like a flexible sheet located between the thoracic cavity and the abdominal cavity. When it moves downward, we breathe in; when it moves upwards, air is pushed out of the lungs, facilitating breathing.

Q5: How does the exchange of oxygen and carbon dioxide take place in the lungs?

Answer: In the lungs, oxygen from the inhaled air passes into the thin blood vessels around the alveoli and is carried to all parts of the body. At the same time, carbon dioxide brought by the blood from the body enters the air in the alveoli and is exhaled.

Q6: What are the ill effects of smoking on the lungs?

Answer: Smoking causes toxic substances to collect in the respiratory tract, reducing the efficiency of the lungs, increasing the likelihood of lung diseases (including lung cancer), and reducing the oxygen supply to the body due to a sticky layer inside the alveoli.

Q7: What is passive smoking?

Answer: Passive smoking refers to facing the consequences of smoking even if one does not smoke oneself, due to being around people who smoke.

Q8: What is the alimentary canal?

Answer: The alimentary canal is a long and flexible tube inside our body, extending from the mouth to the anus, where the digestion of food takes place.

Q9: Name the main organs of the digestive system.

Answer: The main organs of the digestive system are the mouth, oesophagus (gullet), stomach, small intestine, large intestine, rectum, and anus. Salivary glands, liver, and pancreas also assist in digestion.

Q10: What is the function of the stomach in digestion?

Answer: In the stomach, food is churned, digestive juices bring about digestive processes, and some disease-producing germs in the food are destroyed. Food changes into a thin slurry here.

Q11: Why is sufficient water necessary for digestion?

Answer: Sufficient water is necessary for the processes of digestion to take place properly and for the food to keep moving through the alimentary canal. Lack of water can lead to constipation.

Q12: What is a 'system' in the context of the human body?

Answer: A group of organs which work together to carry out a function of the body is called a system. For example, the respiratory system.

Q13: What is the main function of the circulatory system?

Answer: The main function of the circulatory system is to keep the blood flowing continuously through all parts of the body, carrying oxygen and energy-giving substances.

Q14: What is the hardest substance in our body and what is its function?

Answer: Enamel is the hardest substance in our body. It covers and protects the delicate inner parts of the tooth.

Q15: What is the main function of the nervous system?

Answer: The nervous system, consisting of the brain and a network of nerves, functions to coordinate all our bodily functions and carry messages between the brain and different parts of the body.

Application-Based Questions

Q16: Why do we breathe faster after running a hundred metres?

Answer: We breathe faster after running a hundred metres because our body needs more oxygen to produce the extra energy required for physical activity. Faster breathing helps to take in more oxygen and expel more carbon dioxide.

Q17: Why is it important not to eat in a hurry or speak while eating?

Answer: It is important not to eat in a hurry or speak while eating because the upper ends of both the oesophagus (food pipe) and the windpipe (air pipe) open in the throat next to each other. If we eat in a hurry or talk, food may accidentally enter the windpipe and cause us to choke.

Q18: How does the body get energy from the food we eat?

Answer: Substances formed during digestion mix with the blood and reach all parts of the body. Oxygen, obtained through respiration and carried by blood, helps in the slow burning of these substances (fuel) in the body, which releases energy for all our tasks.

Q19: If a person drinks alcohol for a long time, how does it affect their digestive organs and other systems?

Answer: If a person drinks alcohol for a long time, it can cause ulcers on the inner lining of the digestive organs. It can also seriously affect the functions of the liver and kidneys, and impacts the nervous system leading to loss of control and lack of coordination.

Q20: Why is it dangerous to drive after drinking alcohol?

Answer: It is dangerous to drive after drinking alcohol because alcohol affects the nervous system, leading to drowsiness, confusion, and loss of control over body movements and coordination. This impairs a person's ability to react quickly and safely, making driving hazardous.

Q21: What happens if the function of any one of our body systems is disturbed? Give an example.

Answer: If the function of any one of our systems is disturbed, it affects all the other systems in the body too. For example, if the digestive system is not working properly, the body may not get enough energy, which would then affect the ability of the circulatory and nervous systems to function optimally.

Q22: Why should we look after our teeth carefully?

Answer: We should look after our teeth carefully because each tooth has a covering of enamel, the hardest substance in our body, which protects its delicate inner parts. If we do not keep our teeth clean, even this enamel can corrode, leading to tooth decay and damage to the tooth's inner parts.

Higher-Order Thinking Questions

Q23: "The body is like a complex machine." Explain this analogy by referring to the different systems in the human body.

Answer: The body is like a complex machine because, just like a machine has different parts working together for a purpose, our body has various **systems** (like respiratory, digestive, circulatory, nervous) that work in **coordination** to perform vital functions. If one part of a machine breaks, the whole machine might stop; similarly, if one body system is disturbed, it affects all others, highlighting the intricate and interdependent nature of our internal organs and systems.

Q24: A person has fainted and a crowd of people has surrounded him. What immediate actions would you take based on your understanding of the respiratory system?

Answer: Based on the understanding of the respiratory system, the immediate action would be to **clear the crowd** around the fainted person. This is crucial to ensure they get a continuous supply of fresh air, which is essential for breathing and providing oxygen to the body. Lack of fresh air due to a crowd could worsen their condition.

Q25: How do the respiratory and circulatory systems work together to provide energy to the body?

Answer: The respiratory and circulatory systems work closely together. The **respiratory system** (lungs) takes in oxygen from the air and releases carbon dioxide. This oxygen then enters the blood. The **circulatory system** (heart and blood vessels) then pumps this oxygen-rich blood, along with energy-giving substances from digested food, to all parts of the body. In the body cells, oxygen helps in the slow burning of these substances, releasing the energy needed for all bodily tasks.

Q26: Why is it important for us to pay attention to changes in the taste or smell of food?

Answer: It is important to pay attention to changes in the taste or smell of food because these are often signs that the food has **spoiled**. Spoiled food may contain disease-producing micro-organisms or toxic substances that can cause food poisoning or other illnesses if consumed. By noticing these changes, we can avoid eating bad food and protect our health.

Q27: How does the ban on smoking in public places contribute to public health, even for non-smokers?

Answer: The ban on smoking in public places contributes to public health by protecting non-smokers from **passive smoking**. When people smoke in public, the harmful substances in the smoke spread in the air, and non-smokers breathe them in, facing similar health risks as smokers. The ban ensures cleaner air in public spaces, reducing the exposure of non-smokers to these toxic substances and preventing respiratory and other diseases in the wider community.

Q28: Explain how the nervous system acts as the 'coordinator' of all bodily functions.

Answer: The nervous system, comprising the brain and a network of nerves, acts as the 'coordinator' by sending and receiving messages to and from all parts of the body. It ensures that all different bodily functions (like breathing, digestion, circulation, and voluntary movements) occur at the right time and in the right manner. For instance, it tells salivary glands to secrete saliva when food is in the mouth or ensures respiration continues ceaselessly, thus maintaining overall bodily harmony and function.

Q29: What are the ethical implications of consuming substances like alcohol that can affect the nervous system and lead to loss of control?

Answer: The ethical implications of consuming substances like alcohol that affect the nervous system include the potential for **harm to oneself and others**. Loss of control can lead to dangerous behaviors (like drunk driving, causing accidents), impaired judgment, and inability to fulfill responsibilities, impacting family, work, and society. Ethically, it raises questions about personal responsibility, public safety, and the moral obligation to avoid actions that can cause harm due to impaired faculties.

References

1. Maharashtra State Board Environmental Studies (Part One) Standard Five Textbook (2015 Edition) - Chapter 21: Busy at Work - Our Internal Organs, pages 107-114.
2. Maharashtra State Board 5th Standard Environmental Studies Syllabus.
3. Balbharati Environmental Studies Part 1 Textbook.