autotrophs

We use our tongue for talking and taste. Besides, it mixes saliva with the food during chewing and aids in swallowing food. We also taste food with our tongue. It has taste buds that detect different tastes of food.

Process of respiration yields energy which is required to perform a variety of routine activities. Thus, it needs to be a continuous process

Low cost onsite sewage disposal system must be encouraged to improve sanitation.

An erect and enlarged image of an object is formed only by the concave mirror or convex lens when object is inverted and placed between F and 2F

The term shimmering means that the air shines with a slightly shaking light.

Move downwards During exhalation the ribs moves downwards causing a decrease in area of chest cavity forcing the air out.

Thermo flask is a special kind of flask for keeping liquids. It prevents loss or gain of heat by any of the three methods. It keeps liquid warm or cold for a long time. It was invented by Sir James Dewan in 1893.
It consists of a double-walled glass-cylinder. A vacuum is created in the space between the double walls. The two inner surfaces of glass walls are silvered. The flask is placed on a spring within a non-conducting cylindrical case to protect it from jerks and breakages. The gaps between flask and outer casing is packed with felt pads. The mouth of the flask is finally closed with a cork.

Since the container is made of glass which is a bad conductor of heat and therefore, the loss or gain of heat due to conduction is prevented. As there is vacuum between the double walls, it prevents transmission of heat by convection. Due to silvering of the inner surfaces, the heat loss by radiation is prevented. The cork and the felt pads also help to preserve the heat inside the flask. So, the hot liquids like tea, coffee, etc., remain hot and cold liquids like water, juice, etc., remain cold for a long time.

(i) Size of image of jug is 1cm.
(ii) Distance between image of jug and mirror is 5 cm.

(a) Animals that can breathe only through skin are earthworm and leech.
(b) Animals that can breathe through skin as well as through lungs are frogs.
(c) Animals that can breathe through lungs are buffaloes, human, and dolphins.
(d) Animals that can breathe through gills are tadpole and fish.
(e) Animals that can breathe through spiracles and tracheae are grasshopper, cockroaches, ants, housefly and mosquito.

(a) The sequence of living organisms in which one organism eats another is called a food chain.
(b) \(\underset { (Procedur) }{ Grass } \longrightarrow \underset { (Herbivore) }{ Insect } \longrightarrow \underset { (Carnivore) }{ Frog } \longrightarrow \underset { (Large\quad carnivore) }{ Snake } \longrightarrow \underset { (Top\quad carnivore) }{ Eagle } \)
(c)Scientific attitude, Obligation to maintain the ecosystem of nature.

(a) The various important component of soil are air, water, rock particles, minerals,
humus and living organisms like bacteria fungi, worms (earthworm), rodents, insects (ant and beetle), etc.
(b) The increasing order of rock particles are
Clay \(\rightarrow\)  Silt \(\rightarrow\) Sand \(\rightarrow\) Gravel
(c) The figure shows waste rnaterial like polythene bags, plastics, glass and metal objects are dumped which causes soil pollution.

The inner lining of stomach secretes the following component:
(i) Mucous: It protects the lining of stomach. 
(ii) Hydrochloric acid: It kills the germs and makes the food acidic. 
(iii) Digestive juices: They help to break the proteins into simple substances.

The two effects of electric current are
(i) Heating effect
(ii) Magnetic effect

All green plants are producers. They make food by the process of photosynthesis using water CO₂ and sunlight. All forms of animals depend on plants for food. So, if there no plants, no food will be there. Plants are give oxygen also during photosynthesis, and there would be no oxygen in absence of plant. These two basic needs make plants important for us and we cannot think of life without plants.

The vertical section of heart shows that heart is divided into four compartments called as chambers.
(a) The upper two chambers of heart are called atria or atrium.
(b) The lower two chambers of heart are called ventricles.

Burning of wood is a chemical change while cutting of wood is a physical change because, during burning, new substances are formed. After burning, we cannot get original substance (i.e. wood) back. Cutting of wood into small pieces is a physical change because no new substance is formed.