Students should refer to the below Life Process Class 10 notes prepared as per the latest curriculum issued by CBSE and NCERT. These notes and questions are really useful as they have been developed based on the most scoring topics and expected questions in upcoming examinations for Class 10. Life Process is an important topic in Science Class 10 which if understood properly can help students to get very good marks in class tests and exams.
Life Process Class 10 Notes and Questions PDF Download
Read the notes below which will help you to understand all important and difficult topics in this chapter. There are some topics in Life Process chapter which you should understand carefully as many questions can come from those parts. Our team of teachers have designed the revision notes so that its helpful for students to revise entire course prior to the class tests.
All living things perform certain life processes like growth, excretion, respiration, circulation etc.
All the processes like respiration, digestion, which together keep the living organisms alive and perform the job of body maintenance are called life processes.

Autotrophic Nutrition :
The organisms which carry out autotrophic nutrition are called autotrophs (green plants) Autotrophic nutrition is fulfilled by the process bywhich autotrophs take in CO2 and H2O and convert these into carlohydrates in the presence of chlorophyll, sunlight is called PHOTOSYNTHESIS
Equation :
Raw Materials for Photosynthesis :
♦ Sunlight
♦ Chlorophyl → Sunlight absorbed by chlorophyll
♦ CO2 → enters through Stomata, and Oxygen (O2) is released as by product through stomata on leaf.
♦ Water → water + dissolved minerals like Nitrogen phosphorous etc are taken up by the roots from the soil.
Site of Photosynthesis :
Chloroplast in the leaf. Chloroplast contain chlorophyll. (green pigment) Main Events of Photosynthesis :
♦ Absorption of light energy by chlorophyll
♦ Conversion of light energy into chemical energy + splitting (breaking) of water into hydrogen and oxygen.
♦ Reduction of CO2 to carbohydrates.
STOMATA : Tiny pores present on the surface of the leaves
FUNCTIONS :
(i) Exchange of gases O2/CO2
(ii) Loses large amount of water [water vapour] during transpiration.

How do organisms obtain their food
Unicellular / single celled organism : food is taken up through entire surface.
Example : (i)Amoeba. (ii) Paramaecium


Small Intestinal →

Small Intestine → Villi → helps in absorption of food into the blood.
[finger like projections]
small intestine → Receives
secretion from

Emulsification : The process of breakdown of large fat
globules into smaller fat globules by bile juice.
Large intestine → Absorb excess of water.
→ The rest of the material is removed from the body via the anus. (Egestion)

Respiration
Respiration involves
(i) Gaseous exchange : Intake of oxygen from the atmosphere and release of CO2 → Breathing
(ii) Breakdown of simple food in order to release energy inside the cell → Cellular Respiration
Breakdown of Glucose by various pathways

Human Respiratory System
Passage of air through the respiratory system.
Nostril
↓
Nasal Passage
↓
Nasal Cavity
↓
Pharynx
↓
Larynx
↓
Trachea
↓
Bronchi
↓
Lungs
↓
Bronchioles
↓
Alveolar → Blood capillaries


* During inhalation the thoracic cavity (chest cavity) expands * Thoracic cavity contracts
* Ribs lift up * Ribs move downwards Diaphragm
becomes dome shaped
* Diaphragm become flat in shape * Volume of lungs decreases and air
exits from the lungs.
* Volume of lungs increases and air enters the lungs
Terrestial Organism – use atmospheric oxygen for respiration
Aquatic Organisms – used dissolved oxygen for respiration
Respiration in Plants :
Respiration in plants is simpler than the respiration in animals. Gaseous exchange occur through
1. Stomata in leaves
2. Lenticels in stems
3. General surface of the roots.
Life Process (II)
Transporation and Excretion
– Human beings like other multicellular organism need regular supply of food, oxygen etc., This function is performed by circulatory system or Transport system.
– The circulatory system in human beings consists of :
The circulatory system in human beings consists of :
↓———————————↓—————————————-↓
A Pumping Organ Blood vessels A circulatory medium
Heart –Arteries & Veins Blood & Lymph
Deoxygenate Vena Right Right Right
Blood → Atrium → Atrium → Ventricle
(from body) Cava (Relaxed) (contracts) (relaxed)
↓
Body Parts Blood Circulation Right
via ↑ AoRTA in Human Heart ventricle
contracts
↓
Lungs
Left Left ← Left ← Left ← Oxygenated
Ventricle Atrium Atrium Atrium blood
(contracts) (relaxed) (contracts) (relaxed)


– Lymph – a yellowish fluids escapes from the blood capillaries into the intercellular spaces contain less proteins than blood. Lymph flows from the tissues to the heart assisting in transportation and destroying germs.

– Transpiration is the process of loss of water as vapour from aerial parts of the plant.
Function :
1. Absorption and upward movement of water and minerals by creating PULL.
2. helps in temperature regulation in Plant.
– Transport of food from leaves (food factory) to different part of the plant is called Translocation.
EXCRETION
– The process of the removal of the harmful metabolic wastes from the body.
– Excretory system of human beings includes :
1) A pair of kidneys
ii) A Urinary Bladder
iii) A pair of Ureter
iv) A Urethera
– Urine produced in the kidneys passes through the ureters into the urinary bladder where it is stored until it is released through the urethera.
– The purpose of making urine is to filter out waste product from the blood ie, urea which is produced in the liver.
– Each kidney has large numbers of filtration units called nephrons.
– The Urine formation involves three steps
1. Glomerular Filtration : Nitrogenous wastes, glucose water, amino acid filter from the blood into Bowman Capsule of the nephron.
2. Tubular reabsorption : Now, useful substances from the filtrate are reabsorbed back by capillaries surrounding the nephron.
3. Secretion Extra, water, salts are secreted into the tubule which open up into the collecting duct & then into the ureter.
– Haemodialysis : The process of purifying blood by an artificial kidney. it is meant for Kidney failure patient.
Excretion in Plants

– Other wastes may be stored in leaves, bark etc. which fall off from the plant.
– Plants excrete some waste into the soil around them.
– Gums, Resin ® In old Xylem
– Some metabolic wastes in the form of crystals of Calcium oxalates in the leaves of colocasia and stem of Zamikand.
Question: What is ‘clotting of blood’? Write a ow chart showing major events taking place in clotting of blood?
Ans. Formation of clot at the site of injury to stop bleeding is known as ‘clotting of blood’. Steps for clotting of blood –

Question: With the help of a labelled diagram of human excretory system, Mention its important part and explain
them.
Ans. 1) Kidney – It is the functional unit of excretory system. Each kidney is made up of about million microscopic coiled channels called nephrons. Nephrons are the basic filtration unit in the kidneys. It consists of – Glomerulus’s, Bowman’s capsule, convoluted tubule.

2) Ureter – Wastes comes out of the kidney into the ureter.
3) Urinary bladder – Ureter pours its contents into a muscular sac called the urinary bladder.
4) Urethra – Urine flows from bladder to the outside through the urethra
Question: Why is it necessary to separate oxygenated & deoxygenated blood in mammals & birds?
Ans. Separation of oxygenated and deoxygenated blood allows good supply of oxygen to the body. This system is useful in animals that have high energy requirement Mammals and birds constantly need oxygen to get energy to maintain constant body temperature
Question: With the help of labeled diagram, Discuss the mechanism of respiration in human beings.
Ans. Mechanism of Respiration – It occurs in following steps
a) Breathing – Taking in oxygen and expelling carbon – dioxide out is called breathing. It involves following steps –
(i) Inhalation – It is taking in oxygen. It occurs due to contraction of muscles attached to ribs. This lifts ribsand flatter diaphragm, which increase the volume of thoracic cavity. Hence the pressure inside thethoracic cavity decreases and air rushes inside of the lungs.
(ii) Exhalation – It is expelling of carbon – dioxide. It occurs due to relaxation of muscles attached to ribs and diaphragm is done shaped. This decreases the volume of thoracic cavity and decreases air pressure and expels out of the lung.
b) Exchange of gases – It takes place between the alveoli of lungs and surrounding blood capillaries.
c) Transport of gases in blood – Hemoglobin present in the blood transport. in blood. Oxygen is transport from the lungs to the body cells in the form of any hemoglobin.
d) Oxidation of food – Break down of glucose molecules which produce energy. It occurs is into chondria.
Question: Differentiate between single and double circulation found in vertebrates.
Ans.

Question: What is the difference between arteries & veins?
Ans.

Question: Discuss the mode of nutrition in amoeba.
Ans. Steps of Nutrition in amoeba –
a) Formation of pseudopodia – When Amoeba comes in contact with a food particle, it forms pseudopodia
which envelops food particles.
b) Ingestion – The tips of pseudopodia fuse with each other, together with variable amount of food particles and water, forms food vacuole, this process is known as ingestion.
c) Digestion – The vacuoles are surrounded by lysosomes which fuses with vacuole and digest the food particles present in vacuole.
d) Exocytosis – The soluble products of digestion are passed out into due cytoplasm from the food vacuole.
And the remaining undigested materials are passed out of the body with the help of a process called exocytosis.
Question: What is role of skin, lungs and intestine in the process of excretion in man?
Ans. Skin – Skin excrete excess salts and water in the form of sweat.
Lungs – Lungs expel carbon – dioxide during exhalation.
Intestine – Intestine throw out undigested food in the form of faeces through anus
Question: What do you mean by ‘lymph’. Mention its function.
Ans. Lymph- The fluid present in the spaces between the cells in the tissues is called tissue fluid or lymph.
Functions of lymph:
(i) It returns tissue fluid from the interstitial spaces into the blood.
(ii) Lymph capillaries of intestinal villi called lacteals helps in absorption of fats.
(iii) It collects carbondioxide, waste products and metabolites form tissues via tissue fluid.
Question: Differentiate inhalation and exhalation.
Ans.

