Methods of Preserving Food   Pasteurization:   i) This method is used to preserve milk and is discovered by Louis Pasteur.   ii) In this process milk is heated to 71 C and then cooled rapidly.   iii) The bacteria become retorted in growth.   iv) Hence the milk is preserved for few days.  …

Note on Exchange of Gases in Aquatic Animals   Through Skin:   The skin of aquatic animals is moist and rich with blood so that oxygen can diffuse directly. Frog and tortoises breathe through skin during hibernation.     Through Gills:   Gills are very effective for gaseous exchange in aquatic animals. Some animals have…

Importance of Anaerobic Respiration   i) In the early time earth had environment, which was totally devoid of oxygen. The aerobic organism cannot exist in anaerobic environment.   ii) Some existing organism like bacteria and parasites have anaerobic respiration. Many useful bacteria and yeasts are anaerobic.   iii) Aerobic respiration is also earlier stage of…

Modes of Nutrition in Animals   There are two methods of nutrition in uni-cellular animals:     Holozoic Nutrition:   Some unicellular animals take in solid particles of food materials called holozoic feeders. And this nutrition is called holozoic nutrition.     Sagrozoic Nutrition:   Some unicellular animals absorb liquid organic materials called saprozoic feeders.…

Modes of Nutrition in Plants   The mode of nutrition in plants are as under:   Parasitic Plants:   i) These plants cannot prepare their own food.   ii) They depend on host.   iii) They have special roots called haustoria, which penetrate into vascular bundles of host and draw food material.   iv) Dodder…

Is Carbon Dioxide Released in Aerobic Respiration   i) Set up the apparatus as shown in fig (* see fig form book)   ii) Pour concentrated soda lime (KOH) in U tube and set in the bottle with the help of glass tube in such a way that it is in contact with the limewater…

Types of Chemical Fertilizers   There are two types of fertilizers:     Organic Fertilizers:   The decaying animals refuse and excreta along with rotten leaves and fruits form useful humus. This humus when mixed with soil, it increases the fertility of soil. This type of fertilizer is called organic fertilizers.     Inorganic Fertilizers:…

Difference between Aerobic & Anaerobic Respiration   Aerobic Respiration:   i) Oxygen is necessary.   ii) 1 gm glucose release 36 ATP energy.   iii) Chemical products are inorganic compounds.   iv) Enzymes are found in mitochondria.   v) It provides the source of energy for organism.     Anaerobic Respiration:   i) Oxygen is…

How do Plants get Minerals   Plants absorb water form soil through root hairs. This water contains dissolved salts and minerals. On the basis of need of salts minerals are divided into two types:   Macronutrients:   Minerals, which are required in higher amounts to the plants, are called macronutrients.     Micronutrients:   Minerals,…

Type of Energy Released During Respiration   i) Arrange the apparatus as show n in figure. (see fig from book)   ii) Take pea seeds and soak them in water for 24 hours.   iii) Wash the seed with germicide (01% chlorine solution) to kill bacteria or fungi   iv) Take some seeds and boil…