Class 10 Science Chapter 5 Important Questions

The various life processes which take place in the living organism are called metabolic activities or metabolism. These life processes can either be anabolic or catabolic in nature. Nutrition, respiration, transportation and excretion are some of the life process that are essential for the functioning as well as maintenance of living organism.

Nutrition is defined as a process a process by which living organism procure food or synthesize it and convert it into simple absorbable form by serious of biochemical process. Nutrition can be defined as the substance which an organism obtains from its surrounding and use it as a source of energy as well as provide raw material for the biosynthesis of body constituent. There are two basic mode of nutrition are
(i) Autotropic
(ii) Heterotrophic
(iii) Holozoic

Autotropic: In autotropic nutrition organism manufacture their own food from simple inorganic raw materials. Majority of green plant are capable of manufacturing their own food in the presence of light by using water and carbon dioxide.
Heterotrophic: Heterotrophic organism cannot prepare their own food. They depend on plants, animal or on dead decay organic materials for their food. Saprophyte derive their nourishment from dead decaying matter.
Holozoic: Holozoic nutrition is a mode of nutrition which involves swallowing of solid food material. Ingestion, digestion, absorption, assimilation and egestion are the various steps involved in holozoic nutrition.

Photosynthesis can be define as the synthesis of organic compound(carbohydrates) from CO2 and H2O using radiant energy or solar energy by chlorophyll molecules. The process of photosynthesis involving two phases: Light reaction and dark reaction.
The following event occurs during the process of photosynthesis:
(i) Absorption of light energy by chlorophyll.
(ii) Conservation of light energy to chemical energy as well as splitting of water molecules into hydrogen and oxygen.
(iii) Reduction of carbon dioxide to carbohydrate.

(i). Digestion start in mouth:
Teeth chew food, Salivary gland release Salivary Amylase which digest or broke down complex starch into simple sugar(maltose) tongue mix chew food into saliva which is known as mastigation. It makes the food soft and slippery
(ii). Food pipe (OESOPHAGUS)
It is a type of connectivity between mouth and stomach the muscle of Oesophagus regularly contract and relax which is stand to food into the stomach this motion is known as peristaltic movement.
(iii). Stomach: The wall of stomach has many gastric glands that produce gastric juice which contains HCL, Mucus, Pepsin.
HCL: It kill germs and create acidic medium for the action of pepsin (a protein digestive enzymes)
Mucus: The wall of stomach has many hairs like structure called mucus that prevent the action of HCL on the wall of stomach here food is converted into partially digested semisolid form.
Pepsin: Pepsin digest protein in acidic medium.
(iv). Small Intestine: Finally digestion of food occurs in small intestine. The semi digested food goes into small intestine with the help of Sphincter muscle. Their many types of enzymes are secreting by liver and pancreas
(v) Liver: It is a largest gland of our body it secretes bile juice that help in digestion of fat by breaking it into small globules of fat this is known as emulsification of fat. Bile juice make the medium alkaline in the small intestine that help intestinal juice to help inn digestion of food.

Trypsin: Trypsin digest protein and convert into Peptones, Peptides and amino acids.
Lipase: Lipase convert fat globules fatty acid and glycerol.
Pancreatic amylase: Pancreatic amylase convert carbohydrate into simple sugar.

Digested food passes through of villi and enters into the blood flowing in the capillaries in the villi. Villi makes the lining of wall of intestine rough that increase the surface area for absorption of food.
Assimilation: The blood carries the digested food to cell and the excessive absorbed food that is not utilized is stored in the liver as Glycogen (It is said to be animal starch).
Large Intestine: The undigested and unabsorbed food passes through large intestine here water and salt absorbed from undigested food and rest are spell out to anus (Anus contain Sphincter machine).

The real site of photosynthesis in plant in chloroplast. Present in middle portion of leaf called mesophyll layer. Plant prepare glucose(C6H12O6) and stored as a starch (Complex sugar)
(i) Upper layer of leaf is known as Epidermal.
(ii) Middle part of leaf is known as Mesophyll.
(iii) Lower part of leaf is known as Epidermal.
In Chloroplast there are three type of pigment are present.
(i) Green pigment
(ii) Colour pigment
(iii) Colourless pigment

The type of nutrition in which organisms derive their food (nutrients) from other living organisms. In heterotrophic nutrition, the energy is derived from the intake and digestion of the organic substances, normally of plant or animal tissue.
Heterotrophic mode of nutrition is of different types:
(i) Saprophytic Nutrition: Organisms that feed on dead decay body is known as saprophytes and this process is known as saprophytic nutrition. For example, Mushroom, Fungi, Bacteria and Yeast etc.
(ii) Parasitic Nutrition: It refer to the mode of obtaining food synthesis by others. The organism which obtain food is called parasite and the organism from which food is absorbed is called the Host. The nutrition is absorbed in Fungi, Bacteria, a few plants like cuscta and some and some animal like Plasmodium and roundworm.
(iii) Holozoic Nutrition: It refer to the mode of nutrition in which the complex organic matter in the form of solid food is ingested digested and then absorbed into the cells and utilized, example Amoeba, frog, human being.

Ingestion: The taking in of food.
Digestion: The process of converting complex food into simple soluble form by action of enzymes.
Absorption: The mixing of simple soluble food into blood.
Assimilation: The process by which food is transported to cells for its utilization.
Egestion: The removal of undigested food outside the body.

Blood. We have four to six liters of blood. It is also known as connective tissue. That is the transport medium of the circulatory system. The two main function of blood are to transport nutrients and oxygen to the cells and to carry carbon dioxide, urea and other waste from the cell.
COMPONENT OF BLOOD ARE:
RBC: RBC are five million in numbering in our body. RBC contain hemoglobin which helps in carrying oxygen with blood. The red colour of blood is only due to the presence of hemoglobin.
Enzymes: Exocrine gland.
Hormones: Endocrine gland.
The excess of RBC has been destroyed by liver. RBC are biconcave discs have no nucleus which gives largest surface area and allowing them to fold up and passed through the smallest capillaries.
WBC: WBC help in making the immune system of the body. It creates antibodies. When bacteria enter in our body.
Blood Platelets: Platelets are rounded, colourless, biconvex and non-nucleated cells which help in coagulation of blood. They are called thermobocytes, they are formed in bone marrow.
Blood Plasma: Approximately 55% of blood is made up of plasma. It is 90% water and 10% dissolved molecules. It is of three type Albomins(helps in water regulation), Immunoglobins (antibodies), Fibrinogen.

Blood perform the following function:
(i) Transport of oxygen: Red blood corpuscles contain hemoglobin that combines with oxygen to form oxyhemoglobin which is transported to the tissue of the body for the purpose of respiration.
(ii) Transport of carbon dioxide: Carbon dioxide produce by the tissues as a result of respiration in transported by the blood plasma and also by the hemoglobin to the lungs from where it is removed.
(iii) Transport of Nutrients: The digested and absorbed nutrition like glucose, amino acid, fatty acid, vitamins, etc. are first transported to the liver and then to the whole of tissues for their storage, Oxidation and Synthesis to new substance.
(iv) Transport of excretory products: Nitrogenous waste like ammonia, urea and uric acid of body are transported to the kidney by the blood from where they are eliminated.
(v) Regulation of body temperature: The blood flows in all parts of the body so it equalizes the body temperature it carries heat from one place to another place of the body.
(vi) Maintenance of pH: The plasma protein act as buffer system and maintain required ph of the body tissue.
(vii) Transport of Hormones: The plasma of blood transports various hormones from one region to another and bring about the coordination in the working of the body.
(viii) Water balance: The blood maintenance water balance at constant level by disturbing uniformly over the body.
(ix) Protection from diseases: The WBC (eosinophils, neutrophils, monocytes,) engulf the bacteria and other diseases causing organism by phagocytosis. The lymphocytes produce antibodies against the antigens.
(x) Clotting of blood forms a clot at the site of injury, thus preventing further loss of blood. Blood helps in rapid healing of wounds.

(i) The high blood pressure at the end of the capillary belt is much greater than the solute potential of the surrounding cells thus fluid is forced out of the capillaries the meaning of this point.
(ii) At the various and the capillaries belt the blood pressure is very low while the solute potential of the blood is much stronger since the blood is more concentrated.
(iii) The overall effect is to ensure that the tissue fluid is constantly on the move and so every cell in the body receives a fresh supply in neutrates.
Note: Not all of the fluid forced out of the capillaries is returned by the osmosis and the network of vessel which collect this excess fluid is known as Lymphatic system it returns this food to the circulatory system.

It is system of tiny tubes called lymph vessels or lymphatic and lymph nodes or lymph glands in the human body which transports the liquid, lymph from the body tissues to the blood circulatory system.
Lymphatic system runs parallel to veins consist of the following parts:
Lymph or tissue fluid is colourless containing lymphocyte cells which fight against infection. Lymph flows only in one direction that’s why from tissue in heart. Lymph is also called extracellular fluid as it lies outside the cells. Lymph drains into lymphatic capillaries.
Lymphatic capillaries are thin walled capillaries forming a network in every organ except in nervous system. Lymphatic vessels form a second pathway for fluid returning from the tissues to the heart. The lymphatic capillaries unite to form lymphatic vessels which are very small veins in structure.
Lymph Nodes or Lymph gland are situated in the course of the lymph vessel and generally occur in groups and are oval or kidney shaped. They are rich with phagocyte and lymphocyte thus act as filter for the microorganism.
Function of Lymph are:
(i) Lymph carries digested and absorbed fat from intestine and drains excess fluid from extra cellular space back into the blood.
(ii) It protects the body by killing the germs and draining it out of the body tissues with the help of lymphocytes contained in lymph nodes.

Artierioles branch into network of very small blood vessels now as capillaries these have a very large surface area and thin walls that are only one cell thick. It is in the capillaries that exchange take place between the blood and the tissue of the body. Capillaries are also narrow this shows the blood down allowing time for diffusion to take occur. Tissue fluid is form in the capillary for their walls are leak.

The control originated of cardiac vascular system in the heart. This is a hollow muscular originated that contained of regular interval forcing blood through the circulatory system. The heart is in shape of cone about the size of fist and it located in the center part of thorax between the lungs directly behind the breast bone. The ball of heart is made up of three layer of tissue the outer and the inner layer are epithermal tissue the middle layer is of myocardium. Our heart beats about once every second of every day of our life (approximately our heart beat 2.5 million times from natural to all days the heart can beat heart of two pumps sitting side by side each pump has upper part known as atrium and lower part is known as ventricle. It has totally four chamber hearts. The right side of the heart pump deoxygenated blood from the body into the lungs where gas exchange take place. In that process carbon dioxide is loss to the air and oxygen is absorbed. This oxygen is almost all carried by the RBC. The left side of the heart pump oxygenated blood from the lungs to the rest of the body. The atrium of the heart receive blood coming into the heart that help thick wall so allowing them to be filled easily. They pup the blood into the ventricle. The ventricle pump blood out of the heart and the left ventricle has the thickest wall of the heart because it has to do most of the work to pump blood to all part of the body this is where the blood has the highest pressure.

Blood move through our circulation because it is under pressure caught by the contraction of the heart and by the muscle that surrounded our blood pressure. The measure of this force is known as blood pressure. The blood pressure will away be higher in the two main artery just outside the heart because the pulmonary circulation inaccessible blood pressure is measured in the systematic circulation only that is blood living the left ventricle only normally in the upper atrium.

Systolic Pressure: To measure blood pressure ensure that patient is relax and has not taken any exercise for at least ten minutes. A cuff is inflated around a person arms stopping the flow of blood through the artery the pressure in the cuff slowly released at the same time doctor listen the first sound of blood passing through the artery this means that the ventricle is pumping with enough force to overcome the pressure exerted by the cuff. This pressure is also known as systolic pressure. The systolic pressure is 120 mm/hg.
Diastolic pressure: The pressure continues to release now listening for the disappearance of sound indicating the steady flow of blood. This pressure is known as diastolic pressure. The normal diastolic pressure is 80 mm/hg.

Plant transport system moves energy stored leaves and raw material from roots. These are two path way are constructed as conducting tubes xylem, which move water mineral obtain from the soil and phloem which transport products of photosynthesis from leaves where they are synthesis to other parts of plant.
Transport of water and mineral: Plant require water for making by photosynthesis and also need minerals salt for various purposes. The water and mineral are absorbed from soil by the roots of the plants and transported to various part of the plant like stem, leaf, flower.

Xylem: It is a tissue that transport water and mineral from the roots to all part of the vascular plant.
Xylem consists of four kind of elements:
(i) Vessels
(ii) Tracheids
(iii) Xylem fiber
(iv) Xylem Parenchyma
Phloem: It is a vascular tissue that transport food material in vascular plant from region where they are produced i.e. leaves to region such as growing points where they are needed for the purpose of the storage or consumption. Phloem consist of sieve tubes.

It is defined as the process by which plant lose water in the vapour form from then aerial plants of the plant.
Importance of transpiration:
(i) Ascent of sap: It is the upward movement of cell that’s why water and mineral through the xylem.
(ii) Removal of excess water: Transpiration helps to excess water.
(iii) Cooling effect: Transpiration helps to regulate the temperature of the plant since evaporation reduces temperature.
(iv) Absorption and distribution of salts: The continues water current produced by transpiration help to absorb and distribution the salts.
Evidence of transpiration:
(i) Diameter of tree trunk decreases during day when water loss from leaves is high.
(ii) Breakage of water column through introduction of air into the column stop upward flow of water.

90% of all water taken up by the roots is lost at leaves by evaporation. Water exist the leave through stomata. Water lost through stomata is replaced by the water released from mesophyll cells.

Most water enters through roots hair. Roots hair always turgid due to solute potential. Transport of minerals into roots is done by active transport pumps in the root here plasm membrane to accumulate minerals against the concentration gradient active transport creates solute potential in the roots and water float.

Stomata opening:
(i) Stomata are open when guard cell are turgid (full of water)
(ii) When water potential in guard cell is lower than in cell of mesophyll water enter in guard cell.
(iii) When turgid guard cell deforms and stomata open.
(iv) Guard cell can become hypotonic to the mesophyll cell by increasing their sugar concentration through active photosynthesis.
Stomata closing:
(i) Stomata are close when guard cell is shrink.
(ii) If mesophyll cell loses excessive amount of water they became hypertonic to guard cell and water leave guard cell.

(i) Humidity (decreases the transpiration rate)
(ii) Transpiration rate is also affected by the temperature.
(iii) Carbon dioxide also affect opening and closing which further affect the transpiration rate.
(iv) Deciduous plant loose leave during dry season including winter.
(v) Few leave has thick and hard appearance due to which causes loss of water.

Plant also do respiration through stomata when stomata of plant open then exchange of gases takes place oxygen enters in the plant carbon dioxide excrete out from the plant. But the rate of respiration is very less than the rate of photosynthesis. The oxygen which enters in the plants is used to breakdown the glucose formed during the photosynthesis and give carbon dioxide, water vapour and energy.

It takes place with the help of some specific respiratory organs which filters in different animal groups, according to their habitat. Aquatic animals like frog, fish have muscles gills as respiratory organ land animal like lizard, bird have lungs and insect have air tubes or trachea as their respiratory organ.
Unicellular Organism respire through its cell membrane by the process of diffusion and osmosis.
Respiration through gills: Fish and many of other aquatic animal respire through gills water enters through the mouth of the fish then it filtered through the upper membrane of the gill. The filtered water entered to the gills where exchange of gases take place. The oxygen of water enters into the blood and carbon dioxide enters in the water.
Respiration through skin: Many animals like frog and earthworms respire through skin.
Respiration through lungs: Many animals respire through lungs like human being.

The human respiratory system is composed of a pair of lungs there are attached to a system of cubes which open on the outside through the Nostrils following are the main structure in the human respiratory system.
Nostrils: There are two nostrils which converts to form a nasal passage. The inner lining of the nostrils his line by hairs and remain wet due to secretion of mucus. The mucus and the hair helps in filtering the dust particle out from inhaled hair. Further air is warmed when it enters the nasal passage.
Pharynx: It is a tube like structure which after the nasal passage.
Larynx: This part come after the pharynx. This is also known as voice box. Larynx can be seen in male in the region of throat which is known as Adan’s apple.
Trachea: this is composed of rings of cartilage. It is in the shape of incomplete rings like C shaped cartilage rings prevent the collapse of trachea in the absence of air. The inner lining of is line with mucus.
Bronchus: A pair of bronchi comes out from the trachea with one bronchi going to each lung.
Bronchioles: A bronchi divide into branches and sub ranches inside the lungs. The final bronchioles end with alveoli.
Alveoli: There are air sacs at the end of the bronchioles. Alveoli is compared of a very thin membrane and is the place where blood capillary open. This is alveoli where oxygen mix with blood and carbon dioxide exit from the blood. The exchange of the gases in alveoli take place due to pressure differential.

The breathing mechanism of lungs is controlled by the diaphragm and he some special muscle diaphragm is a membrane which separates the thoraces Chamber from the abdominal cavity when diaphragm move down the lungs expand and air is inhaled when diaphragm moves up the lungs and contract and air is exhaled.

Terrestrial animal take up oxygen from the atmosphere where as aquatic animal need to utilize oxygen present in the water air contain more oxygen as compared to water since the contact of oxygen in air is high the terrestrial animal does not have to breath faster to get more oxygen that’s why terrestrial animal does not have to show various adaptation for better gaseous exchange.

Glucose is first broken down in the cell cytoplasm into a three carbon molecule called pyruvate than pyruvate is further broken down by the different ways to produce energy?

Hemoglobin transports oxygen molecules all the body cell for cellular respiration. The hemoglobin pigments present in the blood gets attached for oxygen molecules that are obtained from breathing it does forms oxyhemoglobin and the blood becomes oxygenated. This oxygenated blood is that distribute to all the body cells by the heart after giving a way oxygen to the body cell blood takes away carbon dioxide which is the end product of cellular respiration now the blood became deoxygenated. Since hemoglobin pigment has less affinity for carbon dioxide. Carbon dioxide is mainly transported in the dissolved form this deoxygenated blood gives carbon dioxide to alveoli and takes oxygen in return.

The exchange of gases take place between the blood of the capillaries that surrounded the alveoli does alveoli is the sight for the exchange of gases the lungs get filled up with during the process of inhalation. There are 300 to 350 million alveoli present in to maximize the area of the lungs.

There are different ways through which waste product excrete out from human body.
(i) Through Lungs: Excretion of carbon dioxide of gas.
(ii) Through Kidney: Excretion of urine.
(iii) Through Sweat gland: Excretion of water.
(iv) Through Anus: Excretion of undigested food.

Digestive enzymes amylase, pepsin, trypsin other enzymes have in breaking down complex food material into simpler substances which can be easily absorbed by the blood and thus transported to all the cells of the body.

Different parts of excretory system are the following:
(i) Kidney
(ii) Ureter
(iii) Urethra
(iv)Nephron (basic unit of kidney)
(v) Urinary bladder
(i) Kidney are the main excretory part of our body there are two kidney present in the body at the back side of abdomen cavity kidney contain 1000 of basic excretory unit known as nephron kidney
(ii) Ureter is a type of duet which collect the urine from both the kidney to the urinary bladder. Urinary bladder is aa temporary storage pouch of urine where all the urine collects and store for some time after it excrete out with pressure through a duct known as ureter
(iii) Urethra is a tube from which urine excrete out from the body.
(iv) Nephron is a basic excretory unit of kidney it is a cup shape ended of a coiled tube called bones that collect the filtrate each kidney has large number of these filtration unit called nephron called packed close together. Some substance in the initial filter such as glucose amino acid salt and a major amount of water are selectively reabsorbed as the unit flows along the tube the amount of water reabsorbed depend on how much excess water there is in a body.
The waste liquid is finally collected by collectively duet which is further join to ureter. Finally, the collected urine goes through ureter and stored for some time in the urinary bladder after sometime it excretes out through urethra.
(v) Urine is a mixture of uric acid, ammonia, some waste water, waste salt etc. of our bod. It is yellow in colour and it smell is due the presence of ammonia.