5th Std EVS 1 Digest Chapter 21 Busy at Work – Our Internal Organs Textbook Questions and Answers
1. what’s the solution?
Question 1.
A person has fainted and a crowd of people has surrounded him.
2. Use your brain power!
Question (a)
Why do we sometimes choke suddenly while eating?
Answer:
The food that we chew in the mouth enters the oesophagus after swallowing. The upper ends of both the oesophagus and the windpipe open in the throat next to each other. When we swallow the food in a hurry while eating, sometimes the food suddenly enters the windpipe causing us to suddenly choke.
Question (b)
How is the air that we inhale purified in our body?
Answer:
The inner lining of the respiratory tract secretes a sticky substance called mucus. It also has hair-like structures called cilia. The air that we inhale is purified with the help of this mucus and cilia. The cilia filter the dust, smoke, micro-organisms etc. and these substances get entangled in the sticky mucus and stick to the inner lining of the nose. Sometimes the cilia push out these substances towards the nostrils which is then blown out by sneezing. Thus this is how air that we inhale is purified.
3. Fill in the blanks.
Question (a)
………………… gas is continuously transported to all parts of the body.
(a) Oxygen
(b) Carbon dioxide
(c) Nitrogen
Answer:
(a) Oxygen
Question (b)
The stomach is like a …………………… .
(a) ball
(b) skin
(c) bag
Answer:
(c) bag
4. Match the columns:
Question 1.
Match the columns:
| Group ‘A’ | Group ’B’ |
| 1. Lungs | (a) Circulation |
| 2. Stomach | (b) Respiration |
| 3. Heart | (c) Co-ordination |
| 4. Brain | (d) Digestion |
Answer:
| Group ‘A’ | Group ’B’ |
| 1. Lungs | (b) Respiration |
| 2. Stomach | (d) Digestion |
| 3. Heart | (a) Circulation |
| 4. Brain | (c) Co-ordination |
5. Answer the following questions.
Question (a)
Name the systems that carry out the different functions of the body.
Answer:
The systems that carry out the different functions of the body are Digestive system, Respiratory system, Circulatory system, Excretory system, Nervous system and Skeletal system.
Question (b)
Describe how the exchange of oxygen and carbon dioxide gases takes place in the lungs.
Answer:
The air that we inhale contains oxygen. This outside air reaches the lungs with the help of the respiratory organs like nose, trachea and diaphragm. When the outside air reaches the alveoli present in the lungs it passes into the thin blood vessels around the alveoli.
With the blood, it flows to the various parts of the body. At the same time the carbon dioxide that is brought by the blood from all parts of the body leave the blood and enters the alveoli. When we exhale this carbon dioxide is given out. In this way the exchange of oxygen and carbon dioxide gases takes place in the lungs.
Question (c)
Why do we call saliva, a digestive juice?
Answer:
The digestive juice are the juices secreted by the glands present outside the digestive system and they help in digesting the food. When food is taken in the mouth, saliva is secreted by the glands called salivary glands into the mouth.
The saliva then mixes with the food that is chewed and it converts the food into soft moist ball called bolus which is easy to swallow. The saliva also digests the starch present in the food. Since saliva helps in digestion of food it, is called a digestive juice.
6. Choose the appropriate word from the brackets:
Question (a)
Respiration takes place because of its up and down movement.
Answer:
diaphragm
Question (b)
The process of keeping the blood flowing continuously throughout the body
Answer:
circulation
Question (c)
Air that enters through the nose and passes into this tube.
Answer:
trachea
Environmental Studies Part 1 Standard 5th Solutions Chapter 21 Busy at Work – Our Internal Organs Additional Important Questions and Answers
Fill in the blanks with the correct answers from the options given below:
Question 1.
The …………………. is present between the thoracic cavity and abdominal cavity below the lung.
(a) stomach
(b) diaphragm
(c) heart
Answer:
(b) diaphragm
Question 2.
The air sacs formed at the end of the last branches of the trachea are called ………………… .
(a) alveoli
(b) thoracic
(c) blood vessel
Answer:
(a) alveoli
Question 3.
The inner lining of the respiratory organs has the fine hair-like structures called ……………….. .
(a) nose
(b) cilia
(c) alveoli
Answer:
(b) cilia
Question 4.
A layer of sticky substances present in the inner lining of the respiratory organ is known as …………… .
(a) mucus
(b) cilia
(c) skin
Answer:
(a) mucus
Question 5.
Smoking causes life threatning diseases like ………………… .
(a) lung cancer
(b) asthma
(c) pneumonia
Answer:
(a) lung cancer
Question 6.
The process of digestion begins in the …………….. .
(a) stomach
(b) oesophagus
(c) mouth
Answer:
(c) mouth
Question 7.
Small intestine of an adult is …………………. long and the large intestine is ………………. long.
(a) 7 mtrs
(b) 1 1/2 mtr
(c) 2 mtrs
Answer:
(a) 7 mtrs, (b) 1 1/2 mtr
Question 8.
………………….. is the hardest substance in our body.
(a) Tooth enamel
(b) Nail
(c) Hair
Answer:
(a) Tooth enamel
Question 9.
…………………… is secreted by the salivary glands.
(a) Mucus
(b) Saliva
(c) Cilia
Answer:
(b) Saliva
Question 10.
It is necessary for the body to get a continuous supply of ………………… .
(a) oxygen
(b) nitrogen
(c) carbon dioxide
Answer:
(a) oxygen
Question 11.
When the diaphragm moves …………….. we breathe in.
(a) upward
(b) sideways
(c) downward
Answer:
(c) downward
Question 12.
The food we eat is ………………….. in our body.
(a) mixed
(b) churned
(c) digested
Answer:
(c) digested
Question 13.
The teeth, tongue and saliva all help to convert food into a soft moist ball called a …………………………. .
(a) bolus
(b) cilia
(c) saliva
Answer:
(a) bolus
Question 14.
As a result of respiration, …………………. enters the blood in the body and spreads to all parts of the body.
(a) carbon
(b) sulphur
(c) oxygen
Answer:
(c) oxygen
Question 15.
The process of keeping the blood flowing through all parts of the body is called ……………….. circulation.
(a) body
(b) blood
(c) oxygen
Answer:
(b) blood
Question 16.
As long as we are alive, the process of blood ………………… goes on continuously, day and night.
(a) respiration
(b) circulation
(c) co-ordination
Answer:
(b) circulation
Question 17.
Maintaining the co-ordination of the different functions in the body is the function of the ……………… .
(a) lung
(b) nerves
(c) brain
Answer:
(c) brain
Question 18.
A network of ………………… carry messages to and fro between the brain and the parts of the body.
(a) nerves
(b) blood vessels
(c) muscles
Answer:
(a) nerves
Question 19.
The brain and the network of nerves are together called the ………………. system.
(a) circulatory
(b) nervous
(c) respiratory
Answer:
(b) nervous
Define the following or Explain the terms:
Question 1.
System
Answer:
A group of organs that carry out similar functions in the body is called a system.
Question 2.
Blood circulation
Answer:
The process of keeping the blood flowing through all parts of the body is called blood circulation.
Question 3.
Digestion
Answer:
The process of converting food to simpler substances which can get mixed into blood easily is called digestion.
Question 4.
Respiration
Answer:
The process of entering of oxygen into the blood, so that it can be used to burn the food and release energy is called respiration.
Question 3.
Choose the appropriate word from the brackets:
(constipation, trachea, diaphragm, circulation, breathing, brain, enamel)
- Maintaining co-ordination between various systems is its function.
- When there is a tooth decay this is corroded a.
- The process of inhaling oxygen and exhaling carbon dioxide.
- Passing hard stool or not passing stool regularly.
Answer:
- brain
- enamel
- breathing
- constipation
4.
Question (A)
Match the columns:
| Group ‘A’ | Group ‘B’ |
| 1. Mouth | (a) Excess water present is absorbed |
| 2. Stomach | (b) Faeces collected |
| 3. Small intestine | (c) Formation of bolus |
| 4. Large intestine | (d) Food absorbed into the blood |
| 5. Rectum | (e) Food changes to thin slurry |
Answer:
| Group ‘A’ | Group ‘B’ |
| 1. Mouth | (c) Formation of bolus |
| 2. Stomach | (e) Food changes to thin slurry |
| 3. Small intestine | (d) Food absorbed into the blood |
| 4. Large intestine | (a) Excess water present is absorbed |
| 5. Rectum | (b) Faeces collected |
Question 5.
Name the following:
- An organ that pumps blood continuously.
- An organ that maintains and co-ordinates the functioning of all the organ systems.
- An organ that expels4faeces.
- Organs which are affected by drinking alcohol for a long period of time.
- A system that gives support and shape to the body.
- A system that expels the waste substances that are formed in the body.
Answer:
- Heart
- Brain
- Anus
- Liver and Kidney
- Skeletal System
- Excretory System
Answer in one or two sentences:
Question 1.
Which organ helps us to enjoy many different tastes and flavours while having our meals?
Answer:
The tongue and the nose help us to sense the taste and flavours while having our meal.
Question 2.
Name the organs of the digestive system. (Use your brain power.)
Answer:
The organs of the digestive system are mouth, oesophagus, stomach, small intestine, large intestine, rectum, anus and all the other outside glands like salivary glands, liver and pancreas.
Question 3.
In which cavity of the body are the brain, lungs, heart and stomach situated and what is its function?
Answer:
The brain is situated in the cranial cavity, the heart and the lung is present the thoracic cavity and the stomach is present in the abdominal cavity. The bones present in the cavity protect these delicate organs.
Question 4.
Which bones protect the brain, heart and lungs and the stomach?
Answer:
The brain is protected by the skull, the heart and lungs are protected by rib cage as they are present inside it and the stomach is protected by strong muscles and by the rib cage.
Question 5.
How is faeces formed?
Answer:
When the digested food and water gets absorbed into the blood, and then what remains behind forms the faeces.
Question 6.
How many times do humans breathe per minute when resting or sitting comfortably?
Answer:
A healthy adult breathes 16-20 times per minute whereas a child of 6 months breathes 25-40 times per minutes and a child of 6-10 years breathes 18-25 times per minute.
Question 7.
How many times does one breathe after running a hundred metre race?
Answer:
When a person runs a race the breath rate is more than 16-20 times per minute for an adult and more than 18-25 times per minute for a child of 6 -10 years.
Give reasons:
Question 1.
Harmful substances like dust, smoke and microorganisms present in the air cannot reach the lungs.
Answer:
The inner lining of the nose has thin hair-like structures called cilia. This inner lining also secretes a sticky substance called mucus. The harmful substances like dust, smoke, micro-organisms etc. are filtered by the cilia and they get entangled in the mucus.
This then sticks to the inner lining of the nose. The cilia sometimes pushes these substances towards the nostril. This is then blown out by sneezing. Thus the harmful substances are prevented from entering the lungs.
Question 2.
Smoking for a long time reduces the efficiency of the lung.
Answer:
When one keeps smoking over a long period of time, the toxic substances in the smoke collect in the respiratory tract. The solid particles in this tobacco smoke form a sticky layer inside the alveoli. As these toxic substances get collected more and more, the exchange of gases like oxygen and carbon dioxide does not take place properly. Therefore, the efficiency of the lung decreases.
Question 3.
It is important to drink adequate quantities of water after eating.
Answer:
Water is absorbed through the alimentary canal and used for all processes. If one does not drink enough water digestion cannot take place properly, as food cannot keep moving properly. This will lead to constipation. Also water absorbed is used for the proper functioning of all other body processes. Therefore, it is important to drink adequate quantity of water.
Question 4.
We must not eat in a hurry and avoid speaking while eating.
Answer:
The upper ends of both the oesophagus and the windpipe open in the throat next to each other. When food is swallowed the wind pipe remains closed. If we eat in a hurry or speak while eating, food may enter the windpipe and cause us to choke. To avoid this from happening, we must not eat in a hurry or speak while eating.
Question 5.
It is dangerous to drive after drinking alcohol.
Answer:
Alcohol affects the nervous system. Hence when one drinks alcohol, one loses control over the movements of the body due to lack of co-ordination. Due to lack of co-ordination while driving when many accidents occur on the road, leading to loss of life. Therefore, it is dangerous to drive after drinking alcohol.
Use your brain power!
Question 1.
Describe which systems work together to provide the body with energy.
Answer:
The oxygen present in the inhaled air enters the blood due to the respiratory system. The food is digested and it also enters the blood due to the digestive system. The blood then flows to every part of the body due to circulatory system and it supplies the digested food and oxygen.
The food acts as fuel and it bums slowly in presence of oxygen releasing energy. This energy is then used by various parts of the body to do work. Thus the respiratory system, digestive system and circulatory system work together to provide the body with energy.
Answer the following questions:
Question 1.
Describe the process of digestion taking place in the stomach.
Answer:
The soft bolus which is swallowed enters the stomach through the oesophagus. Here the food is then churned. The digestive juices mix with this food and bring about some digestive process. At the same time disease producing . germs present in the food are destroyed. The food then changes into a thin slurry’ and passes into the small intestine.
Question 2.
How is food absorbed into the blood?
Answer:
The thin slurry formed in the stomach enters the small intestine. Many glands like liver, pancreas secrete their digestive juices into the small intestine. These secretions help in the digestive process. As a result of these processes, some substances which can easily mix with the blood are formed. These substances are then absorbed into the blood.
Question 3.
Give the functions of the following system, (a) Skeletal System (b) Nervous System (c) Excretory System.
Answer:
(a) Skeletal System gives support and shape to our body. They also protect the important organs like brain, heart, lungs, etc. present in our body.
(b) Nervous System: It helps to co-ordinate the functions of various systems. Thus it maintains the smooth functioning of all the systems.
(c) Excretory System: It helps to expel the waste produced in our body and helps in keeping us
healthy.
Question 4.
How do we inhale and exhale air?
Answer:
When the diaphragm moves down, the air is sucked inside the lung. Thus air is inhaled when diaphragm moves up the air inside the lung is pushed out. Thus the air is exhaled. The up and down movement of the diaphragm causes us to exhale and inhale air.
Question 5.
Draw neat and labelled diagram of:
(1) Respiratory system (2) Digestive system.
Answer:
1. Respiratory system
2. Digestive system
Can you tell?
Question 1.
Name the organs that bring about respiration.
Answer:
The organs that help in respiration are, the nose, the trachea or wind pipe, the diaphragm and the lungs.
Question 2.
How do we know that we are hungry and that we should eat?
Answer:
When the food absorbed in the blood gets exhausted, after release of energy, the message reaches the brain via the network of nerves. Due to this, the brain then gets the signal that the body needs food. We realise we are hungry and we need to eat food.
Question 3.
How do the salivary glands come to know that there is food in the mouth and it is time to secrete saliva?
Answer:
When we eat food the nerve present in the nose and tongue send the message via the network of nerves to the brain. The brain then sends the message to the salivary gland to secrete the saliva. This is how the salivary glands comes to know that there is food in the mouth and it needs to secrete saliva.
Question 4.
What makes respiration and blood circulation go on all the time and the process of digestion happen at the right time?
Answer:
Our body needs energy to do work. Due to this our body requires a supply of oxygen continuously. Thus to supply oxygen continuously respiration goes on continuously. To carry oxygen to all the parts of the body continuously blood needs to circulate. Therefore circulation also needs to go on continuously. When energy is released the food absorbed in the blood gets exhausted. Through the network of nerves the brain gets the message and it signals us that we are hungry and we need to eat food.
The moment we eat food the nervous system brings about co-ordination between the digestive organs and digestion takes place at the right time. Thus respiration and blood circulation go on all the time and the process of digestion happens at the right time.
Glossary:
- moist – slightly wet
- churned – moved vigorously.
- adequate – acceptable in quantity.
- corroded – damaged
- expels – forces out from body.
- choke – difficulty in breathing
- secretes -produces and discharges (a substance).
- slurry – a semi-liquid mixture.