NCERT Solutions for Class 10 Science Chapter 6 – Life Processes, contains solutions to various questions in Exercises for Chapter 6. Life Processes Class 10 NCERT Solutions have been explained in a simple and easy to understand manner. We are providing NCERT Solutions for Class 10 all subjects which can be accessed by clicking here.
NCERT Solutions for Class 10 Science Chapter 6 – Life Processes – NCERT Exercises
NCERT Solutions for Class 10 Science Chapter 6 – Life Processes, Exercises includes all in text and exercise solved questions which helps you to understand the topic covered in Chapter 6 Life Processes Class 10, in a better manner to help you to score good marks in your examinations.
NCERT Solutions for Class 10 Science Chapter 6 – Intext Questions – Page 95
1. Why is diffusion insufficient to meet the oxygen requirements of multicellular organisms like humans?
Diffusion is insufficient to meet the oxygen requirements of multicellular organisms like humans because it is a slow process and multicellular organisms require rapid diffusion of oxygen throughout their large bodies.
2. What criteria do we use to decide whether something is alive?
There are several movements and processes like walking, digestion, breathing, requirement of food and water, etc that can be used as a criteria to decide if something is alive. Many times, a lot of processes are not visible to the naked eyes. In such cases, presence of life is considered as a criteria to decide whether something is alive or not.
3. What are outside raw materials used for by an organism?
Outside raw materials used by an organism are food, water and oxygen. However, the requirements of these raw materials also varies with the complexity and environment of an organism.
4. What processes would you consider essential for maintaining life?
Life processes like respiration, circulation, transportation, digestion, and excretion are essential for maintaining life. These processes help the body of the organism to generate energy, remove waste products and ensure a healthy life.
Intext Questions – Page 101
1. What are the differences between autotrophic nutrition and heterotrophic nutrition?
In autotrophic nutrition, the organism prepares its own food with the help of water, sunlight and CO2 in the presence of chlorophyll. This process is performed by plants and green bacteria and is also called photosynthesis.
Heterotrophic nutrition occurs when an organism is dependent on other organisms for food. All animals and most organisms have a heterotrophic mode of nutrition.
2. Where do plants get each of the raw materials required for photosynthesis?
Plants make food by the process of photosynthesis. The materials required for photosynthesis are carbon dioxide, sunlight, water and chlorophyll.
Carbon dioxide is absorbed from the atmosphere through stomata. Water from ground is transported to the leaves through root, chlorophyll is present in the leaves of the plants and sunlight in daytime gets trapped in this pigment to aid the process of photosynthesis.
3. What is the role of the acid in our stomach?
The acid present in our stomachs is HCl. It has the following roles:
- It creates an acidic environment in the stomach. Due to this, the protein digesting enzyme pepsinogen is activated and converted into pepsin.
- It plays a major role in digestion by breaking down large and complex molecules.
- It also kills of disease causing harmful pathogens o keep us healthy.
4. What is the function of digestive enzymes?
Digestive enzyme aid the process of digestion and make digestion simpler and easier by breaking large food molecules into simpler form. These simpler molecules are easily absorbed by our body giving us energy to function.
5. How is the small intestine designed to absorb digested food?
The surface of the small intestine has small bristles called micro villi. These protrusions increase the surface area of the intestine to facilitate the diffusion of food into blood vessels. The food is absorbed in blood vessels present in the intestine and is carried to the whole body by blood.
Intext Questions – Page 105
1. What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?
Oxygen is more abundant in atmosphere than in water. Terrestrial organisms can easily obtain this oxygen by the process of respiration whereas aquatic organisms need to breathe faster to get the required amount of oxygen to survive.
2. What are the different ways in which glucose is oxidised to provide energy in various organisms?
In a cell, the glucose first breaks into three carbon compounds called as called pyruvate. These compounds further breaks down by either of the two processes given below, depending on the organism.
(i) Aerobic respiration: The pyruvate is broken into water and carbon dioxide, and energy is released. It occurs in the presence of oxygen. This usually occurs in mitochondria.
(ii) Anaerobic Respiration in Muscles: When the oxygen supply is not sufficient in body while running or exercising, the pyruvate is broken into lactic acid.
(iii) Anaerobic Respiration in yeast: Pyruvate is converted into ethanol and carbon dioxide. There is no oxygen present in this process. This is also called fermentation.
3. How is oxygen and carbon dioxide transported in human beings?
Oxygen and Carbon dioxide are transported in human beings are transported by blood. Cells require oxygen and need to get rid of the carbon dioxide released. Oxygen is absorbed by the blood capillaries from the alveoli present in lung by diffusion and is transported to the cells. The carbon-dioxide brought from cells is absorbed by the alveoli from blood capillaries by diffusion.
4. How are the lungs designed in human beings to maximise the area for exchange of gases?
When we breathe in, we lift our ribs, flatten our diaphragm and chest cavity becomes larger. This action leads in inhalation of air and fills the lungs with air. The passage inside the lungs keeps on subdividing into smaller tubes which terminate in a balloon like part called alveoli. This alveoli expands and is filled with air and is the place where exchange of gases takes place. It contains an extensive network of blood vessels where oxygen and carbon dioxide are exchanged.
NCERT Solutions for Class 10 Science Chapter 6 – Intext Questions – Page 110
1. What are the components of the transport system in human beings? What are the functions of these components?
The transport system in human beings consists of the heart, the blood, and the blood vessels. All of these play important roles in our body.
The heart pumps oxygenated blood to be carried throughout the body. It receives deoxygenated blood from body and sends it to lungs for oxygenation. Then it receives oxygenated blood from lungs and pumps it out to be transported to the whole body.
Blood transports oxygen, nutrients, CO2, and nitrogenous wastes to specific site of the body, and blood vessels are the organs that carry the blood to and from the different parts of the body.
2. Why is it necessary to separate oxygenated and deoxygenated blood in mammals and birds?
Mammals and birds are warm blooded animals who have a constant body temperature irrespective of the environment. To maintain this temperature, a lot of oxygenated blood is needed to produce the required amount of energy. To get the maximum out of the circulatory system and make them efficient to produce sufficient energy, it is necessary to separate oxygenated blood and deoxygenated blood.
3. What are the components of the transport system in highly organised plants?
Highly organised plants have the following two main components:
(i) Xylem: Tissues that conduct water and minerals from roots to rest of the plant parts.
(ii) Phloem: Tissues that transport food materials from leaf to other parts of the plant
4. How are water and minerals transported in plants?
Water and minerals in plants are transported by xylem. Xylem are conducting tissues that are interconnected with all the parts of a plant like roots, stem, and leaves to form a continuous system of water-conducting channel. When plant loses water through transpiration, a suction pressure is created that forces water from ground and through roots into the xylem tissues. These tissues carry minerals and water throughout the plants.
5. How is food transported in plants?
Phloem is responsible for transporting food in plants. An osmotic pressure is created when ATP (energy) is spent. Due to this pressure, the food stored in leaves in the form of carbohydrates starts flowing in the phloem and reaches other parts of the plants as per requirement.
Intext Questions – Page 112
1. Describe the structure and functioning of nephrons.
Nephrons are tubular structures made of glomerulus, Bowman’s capsule, and a long renal tube. They are basic filtration units present in kidneys.
The blood initially enters the renal artery which branches into capillaries associated with glomerulus. At Bowman’s capsule, the water and solute are transferred to the nephron. Some substances like glucose, amino acids, salts and a major amount of water, are selectively re-absorbed as the urine flows along the proximal tubule and unwanted substances are added to the urine. This filtrate then moves down into the loop of Henle, where more water is absorbed. After this, the remaining filtrate moves upwards into the distal tubule and gets collected in the collecting duct where urine from many nephrons is collected. This collected urine moves into the urinary bladder via ureter, where it is stored until excreted.
Diagram of nephron:
2. What are the methods used by plants to get rid of excretory products?
Plants get rid of excretory products by many different methods. They get rid of dead cells and leaves by losing them. Some of these leaves may also contain waste products stored in cellular vacuoles. Other waste products are stored as resins and gums, especially in old xylem. Some waste is lost in the nearby soil.
They lose excess water by transpiration.
3. How is the amount of urine produced regulated?
The amount of urine produced depends on the amount of water consumed and the amount of waste produced in the body. Various other factors like hormones, functioning of human, health, and environment.
NCERT Solutions for Class 10 Science Chapter 6 – NCERT Exercise – Page 113
1. The kidneys in human beings are a part of the system for
(c ) Excretion
2. The xylem in plants are responsible for
(a) transport of water
(b) transport of food
(c) transport of amino acids
(d) transport of oxygen
(a) transport of water
3. The autotrophic mode of nutrition requires
(a) carbon dioxide and water
(d) all of the above
(d ) all the above. (by the process of photosynthesis)
4. The breakdown of pyruvate to give carbon dioxide, water and energy takes place in
(b ) mitochondria
5. How are fats digested in our bodies? Where does this process take place?
Food is completely digested in our small intestines. Food components like fats, carbohydrates and proteins are broken down and digested here. To facilitate the process of digestion, the small intestine receives secretions from liver and the pancreas.
First, the acidified food coming from stomach is made alkaline in nature with the help of bile from liver. This allows the pancreatic enzymes to work on it.
The food contains large globules of fats which are difficult to digest. Bile juice breaks down these large globules into smaller units. Then pancreatic juice, which contains enzyme called lipase for breaking down emulsified fats, works on it.
Finally, the walls on the intestine contain glands that secrete intestinal juice. This juice contains enzymes that convert fats into fatty acids and glycerol which can be easily absorbed by the body.
6. What is the role of saliva in the digestion of food?
Saliva contains an enzyme called salivary amylase to break the large starch molecule into smaller sugar molecules. It makes it easier to be absorbed by the alimentary canal, facilitating digestion.
7. What are the necessary conditions for autotrophic nutrition and what are its by-products?
The necessary conditions for autotrophic nutrition include carbon dioxide, sunlight, chlorophyll, water, and ability to store food.
Plants make their own food by the process of photosynthesis. They take carbon dioxide, sunlight present in atmosphere and convert them into starch.
Starch are carbohydrates that give them energy. These are not necessarily used immediately and are sometimes stored for future use.
The by-products obtained in this process are oxygen and carbohydrates.
8. What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.
Difference between aerobic an anaerobic respiration are:
Some organisms that use anaerobic mode of respiration are yeast, some kinds of bacteria and some parasites.
9. How are the alveoli designed to maximise the exchange of gases?
The passage inside the lungs keeps sub-dividing in smaller tubes, which terminate in balloon-like structures, called as alveoli. Alveoli contains a dense network of blood vessels, where the exchange of gases takes place.
As we breathe, we lift our ribs, flatten our diaphragm and our chest cavity becomes larger and air is flushed into the lungs which fills the expanded alveoli. Oxygen is absorbed by the blood capillaries from the alveoli present in lung by diffusion and is transported to the cells. The carbon-dioxide brought from cells is absorbed by the alveoli from blood capillaries by diffusion.
The lungs always contain a residual volume of air between the process of inhalation and exhalation so that there is sufficient time for oxygen to be absorbed and carbon dioxide to be released.
10. What would be the consequences of a deficiency of haemoglobin in our bodies?
Haemoglobin binds oxygen to the blood cells. It is a protein, responsible for transportation of oxygen to the body cells for cellular respiration. In the case of deficiency of haemoglobin, oxygen will not be properly circulated throughout the body, leading to lack of oxygen and hampering some important processes.
The deficiency of haemoglobin is also called anaemia and occurs due to lack of iron.
11. Describe double circulation of blood in human beings. Why is it necessary?
In double circulation of blood, the oxygenated and deoxygenated blood are separated.
In a single cycle, blood goes into heart twice. The double circulation includes pulmonary circulation and systematic circulation.
- Pulmonary Circulation: In this step, the right ventricle pumps deoxygenated blood into the lungs where it is oxygenated. The oxygenated blood is brought back to the left atrium, then it is pumped into the left ventricle and finally blood goes into the aorta for systemic circulation.
- Systematic Circulation: The oxygenated blood then, is pumped to various parts of the body from the left ventricle. The deoxygenated blood from different parts of the body passes through vena cava to reach right atrium. The right atrium transfers the blood into right ventricle. This completes the double circulation.
It is necessary to separate oxygenated and deoxygenated blood for efficient functioning of the circulatory system.
12. What are the differences between the transport of materials in xylem and phloem?
Xylem transports water and minerals from roots to all plant parts. Phloem transports food from leaves to all other parts of plant body.
13. Compare the functioning of alveoli in the lungs and nephrons in the kidneys with respect to their structure and functioning.
- Structure: Alveoli are balloon like structures, are one cell thick, and contain extensive network f blood capillaries.
- Function: Site of exchange of gases in lungs. Oxygen and carbon dioxide are exchanged through the blood capillaries present in and around alveoli.
- Structure: Nephrons are tubular structures made of glomerulus, Bowman’s capsule, and a long renal tube.
- Function: They are basic filtration units present in kidneys. Blood enters the kidney through renal artery and the nitrogenous waste in the form are collected by collecting duct in the form of urine.
Topics Covered in Life Processes Class 10 Science
- What are Life processes?
- Autotrophic Nutrition
- Heterotrophic Nutrition
- How do Organisms obtain their Nutrition?
- Nutrition in Human Beings
- Transportation in Human Beings
- Transportation in Plants
- Excretion in Human Beings
- Excretion in Plants