Ans. Waste water created in flight is stored in a holding tank on the aircraft until the plane sets down. When it's on the ground, a service truck rolls up and pumps the contents of the plane's holding tank aboard. A waste station at the airport serves to empty the truck's tank into the community waste water processing system.

Concave mirror

Transpiration removes extra water from plants through water vapour. It also creates a sunction pull which helps to lift up water from the soil to the xylem of plants. 

No, transpiration is not harmful to plants because it is the process by which excess amount of water is sending out in the form of vapour...

Ans. Rain water and the water from water bodies on earth’s surface pass through the soil by the process of infiltration. The infiltrated water then gets accumulated in the aquifer deep under the ground. There are some layers of impermeable rocks which prevent the water in the aquifer from seeping down further. In this way, the ground water is recharged.

The definition of science is:

• "knowledge attained through study or practice," or
• "knowledge covering general truths of the operation of general laws, esp. as obtained and tested through scientific method [and] concerned with the physical world."

Science refers to a system of acquiring knowledge. This system uses observation and experimentation to describe and explain natural phenomena.The term science also refers to the organized body of knowledge people have gained using that system.Less formally, the word science often describes any systematic field of study or the knowledge gained from it. Thus science is scientific .

Reproductive parts of flower are stamen and pistil or carpel. stamen consists of filament and anther that form pollen grain. carpel consist of stigma, style and ovary, ovule is formed inside the ovary.

Unisexual flowers include- papaya, cucurbits.

Bisexual flower include- China rose, mustard flower.

Rainfall of a place depends on types of vegitation, geographical locations and direction of monsoon winds.

Number of trees in that area

Pollution of particular area

Global warming

Ans. The heat that radiates from the sun and heats up the land begins to heat up the air and then escapes into the atmosphere due to the lack of clouds and humidity. This is the main reason that deserts can be hot during the day but cold during the night.

topsoil

Ans. The process of charging the uncharged object by bringing another charged object near to it, but not touching it, is called charging by induction.

The process of charging the uncharged object by bringing it in contact with another charged object is called charging by conduction.

Ans. 

Crystals of copper sulphate are prepared by the method of crystallization.

The process is as followed:

• Step 1: A cupful of water in a beaker is taken.
• Step 2: Few drops of dilute sulphuric acid is added to it.
• Step 3: Water is heated and when it starts boiling copper sulphate powder is added slowly while    stirring till no more copper sulphate powder dissolved in it.
• Step 4: Solution is filtered and let it cool without disturbance. After some time the crystals of copper can be observed in it.

Ans. White blood cells (WBC) are like an army. They patrol your body constantly, on the lookout for attacks from viruses, bacteria, and other infections. If the scouts find a problem, they sound the alarm and the troops swarm to the site of the attack.

And just like a military is made up of Army, Navy, Marines, and Air Forces, the WBC army also has specialists with names like Neutrophil, Esoniophil, Basophil, Lymphocyte, and Macrophage.

Each "branch" of the WBC military specializes in fighting different kinds of invaders.

They provide immunity to our body. They help in fighting against diseases, infections, allergies and foreign particles. These cells keep our body safe and healthy, much like the soldiers of a nation.

Sewage treatment is the process of removing contaminants from wastewater, primarily from household sewage.It generally involves three stages, called primary, secondary and tertiary treatment.

Because:

1) Can be wisped claen easily after use.

2) Minimizes Noise

3) Absorbs Heat

4) Environment friendy as they are sustainable, recyclable & Biodegradable too

5) Designs may vary & add interest ti a table during meal.

1) Heart Rate is the number of heart beats per minute. On the other hand pulse rate is the measure of palpable blood pressure increases throughout the body.

2) Pulse rate is the expansion and contraction rate of arteries while Heart rate is the expansion and contraction rate of heart.

3) In normal condition the heart rate and pulse rate are same but in abnormal conditions they may vary. Heart beat may be normal but pulse rate may vary due to blockage or hindrance in the path of blood.

Boom: it's a slang which means loud & deep sound.

1) Yeast reproduces by budding 

2) Bread mould reproduces by spore formation

3) and 4) Rose and banana reproduces by vegetative propagation

5) Bacteria reproduces by multiple fission

Ans. Red blood cells transfer oxygen via oxyhaemoglobin formation. Red blood cellshave haemoglobin,it is made up of iron and protein and its each molecule binds about four oxygen molecules. And this is called oxyhaemoglobin. And oxygenmolecules are carried to every cells in the tissue of body and then released.

Ans. Untreated human excretions are a health hazard. It causes pollution of soil and water including the underground water. Thus, it contaminates the sources of water from which people collect water for drinking and household purposes. When this contaminated water is used for drinking, it can cause diseases such as cholera, typhoid, hepatitis, dysentery, etc., which may even lead to death.

Sexual reproduction is the mode of producing offsprings by combination of two distinct sexes.the male produces sperms and the female produces ovum.

It is a mode of reproduction in which two parents are involved to produce their off springs. The male has sperms and female has ova as their reproductive cells. 

Ans. Petrol (known in the US as gasoline), is a product of petroleum, produced by distilling and refining petroleum. Initially produced as a byproduct of kerosene but now is the most popular oil in automotive industries. On average, 44.4% of petroleum is becomes petrol/gasoline where as the rest becomes fuel gas, liquefied petroleum gas (LPG), diesel, kerosene (minyak tanah), asphalt etc. 

Petroleum is unrefined, or crude, oil is found underground and under the sea floor. It is a a thick, flammable, yellow-to-black mixture of gaseous, liquid, and solid hydrocarbons that occurs naturally beneath the earth's surface, can be separated into fractions including natural gas, gasoline (petrol), naphtha, kerosene, fuel and lubricating oils, paraffin wax, and asphalt and is used as raw material for a wide variety of derivative products. 

In short, petroleum is raw oil, petrol is the processed one.

convex mirror -

•  as a car wing mirror ,to see through a wide angle of veiw
• in super markets and big shops and big shops
• in buses ,so thatthe driver can view

concave  mirror -

• as a shaving mirrors or while putting on makeup
• as a dentist mirror for examination.

<font color="#333333" face="Helvetica Neue, Arial, sans-serif">Ans. The main application of concave and convex lenses is as follows:-</font>

• <font color="#333333" face="Helvetica Neue, Arial, sans-serif">Convex and Concave lenses are generally used in both glasses and microscopes.</font>
• <font color="#333333" face="Helvetica Neue, Arial, sans-serif">Both of the lenses are also used in better sight.</font>
• <font color="#333333" face="Helvetica Neue, Arial, sans-serif">They are also used in cameras also.</font>

Concave lenses are used for correcting myopia or short-sightedness. 

Convex lenses are used for focusing light rays to make items appear larger and clearer, such as with magnifying glasses.

Aerobic respiration is the form of respiration which uses oxygen. It can be summarised by this equation:

glucose + oxygen → carbon dioxide + water (+ energy)

Energy is shown in brackets because it is not a substance. Notice that:

• Glucose and oxygen are used up
• Carbon dioxide and water are produced as waste products

Aerobic respiration is the form of respiration which uses oxygen. It can be summarised by this equation:

glucose + oxygen → carbon dioxide + water (+ energy)

Energy is shown in brackets because it is not a substance. Notice that:

• Glucose and oxygen are used up
• Carbon dioxide and water are produced as waste products

Aerobic respiration is the process of producing cellular energy involving oxygen. 

Excretory system is biological system that removes unnecessary excess material from the body fluids of organism so as to maintain balance of chemicals in the body.

The excretory system in human beings includes a pair of kidneys, a pair of ureters, a urinary bladder, and a urethra. This is also known as the urinary system.

The useless products of a forest are biodegradable which get disposed of by the microbs with time.That's why we can say that there is no waste in the forest (Although rotten leaves, fruits etc. can be thought as waste products of forest , but, as the time spends, these wastes get decomposed and provide nutrients to the soil where they fall)