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• Life Processes: Processes which carries out repair and maintenance of living structures.
• Nutrition:  Process of transferring food from outside to inside of body.
• Autotrophic Nutrition: Mode of nutrition in which organism obtain food in form of carbon dioxide and water.
• Autotrophs: Organisms which fulfill their food requirement through autotrophic nutrition. E.g. Green Plants.
• Autotrophic Nutrition – Photosynthesis : [Refer the video to understand in detail]
• Photosynthesis:  “A process in which autotrophs converts carbon dioxide and water into stored form of energy with help of sunlight and chlorophyll”.  

• Raw Materials for Photosynthesis :
1. Sunlight : Energy for photosynthesis is obtained from sunlight
2. Chlorophyll : Cells in green leaves contain chloroplast which have chlorophyll. It captures light energy from sun.
3. Carbon Dioxide :

Exchange of gases takes place through stomata. Guard cells control opening and closing of stomata. It help to prevent loss of water. CO2 is used to produce carbohydrates.

1. Other Raw materials : Water, Nitrogen, Phosphorous, Iron and Magnesium, for production of proteins and other substances.
1. Process of Photosynthesis :   [Refer the video to understand in detail]
1. Light energy absorbed by chlorophyll.
2. Chlorophyll converts light energy to chemical energy which breaks water molecules into hydrogen and oxygen.
3. Reduction of carbon dioxide to carbohydrates
1. Heterotrophic Nutrition: Mode of nutrition in which organism depend on other organism for food. E.g Cow eat grass, big fishes eat small fishes, etc.
• In heterotrophic nutrition, food intake differs from organism to organism. E.g. Humans breakdown food inside the body while yeast breakdown food outside body and again take it inside the body.
• Parasitic nutrition: Food obtained from organism without killing them. E.g. tapeworm, ticks, etc undergo parasitic nutrition.  

 

• Nutrition in single celled organism. Use cell surface to take food inside the body. E.g. amoeba and  paramecium.   

• Heterotrophic Nutrition: Human being    [Refer the video to understand in detail]

 

• Respiration : A life process that supplies oxygen for producing energy from glucose.
• Types of Respiration :
• Aerobic Respiration : Oxygen is used to break glucose into pyruvate in mitochondria of cell, producing energy. E.g. Respiration in humans.
• Anaerobic Respiration : Energy is produced by breaking glucose without using oxygen. E.g. Respiration in yeast cell  
• Breaking of pyruvate molecule in different ways :

• Respiration : Plants
• During day : Plants takes carbon dioxide and releases oxygen
• During night : Plants takes oxygen in small amount and releases carbon dioxide.

 

• Respiration : Animals

 

• Respiration in Aquatic Animals : Respire through gills, which take oxygen dissolved in water and mix it into the blood.       
• Respiration in Terrestrial Animals : Takes atmospheric oxygen inside body through respiratory organs.  
• Respiration in Humans : [Refer the video to understand in detail]
• [Image Reference : Link]
• It is facilitated by inhalation (taking air inside), filtration of air in nostrils, exchange of gases at alveoli, and exhalation (throwing air outside).  
• Alveoli contain complex network of blood capillaries where oxygen mixes in blood and CO2 diffuse in lungs.

• Transportation in Human Being:   [Refer the video to understand in detail]

• Heart: Heart has four chambers. Heart pumps deoxygenated blood to lungs whereas oxygenated blood to whole body parts. During cycle blood is collected twice in heart, hence, it is called double circulation.

• Process of double circulation:
• [ Image reference : Link]

1. Left atrium relaxes and collects oxygenated blood coming from lungs. Left atrium contracts and left ventricle relaxes. Blood is transferred from left atrium to left ventricle via bicuspid valve.
2. Simultaneously, right atrium relaxes and collect deoxygenated blood from body.  Right atrium contracts and right ventricle relax. Blood is transferred from right atrium to right ventricle via tricuspid valve.
3. Valves present at the junction of atriums and ventricles prevents backflow of blood.    
1. Lungs : Lungs collect deoxygenated blood from the heart to alveoli. At alveoli oxygen is added to blood while carbon dioxide is removed. Oxygenated blood is  brought back to heart.   
2. Blood vessels : Arteries, capillaries and veins are blood vessels. Blood exert pressure on walls of blood vessels known as blood pressure.

	Arteries	Capillaries	Veins
Structure	Due to high blood pressure these are thick walled	One cell thick	Due to low blood pressure these are thin walled
Function	Transfer oxygenated blood from heart to body organs	Connects each and every cell and exchange material between blood and connecting cell	Collect deoxygenated blood from blood from body organs to heart
Valves	No Valves	No Valves	Valves prevents backflow of blood facilitating unidirectional flow
Location	Located deep to body surface	Located inside all tissues	Located near the body surface

• Lymph : A fluid containing plasma, protein and blood cells, escaped from capillaries into intercellular spaces. Collected by lymphatic capillaries which joins to form lymph vessels and transferred to larger veins.
• Blood Clotting : During injuries blood flows out of vessel, in such case, platelet cells present in blood, forms clot at injured area, preventing loss of blood.
• Transportation in plant: [Refer the video to understand in detail]

1. Transport of water and minerals: Root hairs buried in earth, collect water by osmosis, and, ions by active transport. Osmosis takes place due to pressure difference, and active transport takes place by intake of ion using stored energy i.e. ATP. Root pressure and transpiration facilitate upward movement of water and dissolved ions through Xylem.  
2. Transport of food and other substance: Food is transported to all body parts through sieve tubes with help of companion cell in vascular tissue called Phloem. Transport of food is called as translocation. Phloem also transports amino acids and other substances. Energy from food is stored in form of ATP.
1. Excretion:
• In Humans: Nitrogenous waste in blood is separated by kidneys. Kidneys have clusters of nephron, which contains a cup shaped  tube which collects filtered urine. Tubes in nephron recollects glucose, amino acid, salt and water. Ureter transfers urine from nephron to urinary bladder. Urine is released outside body through urethra. In case of kidney failure, nitrogenous waste are filtered using artificial kidneys by process of dialysis. [for more details of dialysis refer video]
• In Plants:
1. Waste products like oxygen and water are removed through leaves.
2. In plants, waste products are stored in cell vacuoles.
3. Waste products are stored in leaves that fall from the plant.
4. Waste products are stored in form of gums and resins.