Metals in our body enable the healthy function of the brain and organs.

Metals are elements that are required for several purposes, such as the formation of blood, bones, teeth and other tissues; osmoregulation of body fluids, and the control of physicochemical processes. Some of these metals are only needed in trace amounts.

Macro Elements

• Calcium (Ca)
  Structure of bone and teeth. Also plays a role in the growth of nerve cells.
• Phosphorous (Ph)
  Structure of bone and teeth. Required for ATP, the energy carrier in animals.
• Magnesium (Mg)
  Important in bone structure. Deficiency results in tetany (muscle spasms) and can lead to a calcium deficiency.
• Sodium (Na)
  Major electrolyte of blood and extracellular fluid. Required for maintenance of pH and osmotic balance.
• Potassium (K)
  Major electrolyte of blood and intracellular fluid. Required for maintenance of pH and osmotic balance.
• Chlorine (Cl)
  Major electrolyte of blood and extracellular and intracellular fluid. Required for maintenance of pH and osmotic balance.
• Sulfur (S)
  Element of the essential amino acids methionine and cysteine. Contained in the vitamins thiamin and biotin. As part of glutathione it is required for detoxification. Poor growth due to reduced protein synthesis and lower glutathione levels potentially increasing oxidative or xenobiotic damage are consequences of low sulfur and methionine and/or cysteine intake.

Micro Elements

• Iron (Fe)
  Contained in hemoglobin and myoglobin which are required for oxygen transport in the body. Part of the cytochrome p450 family of enzymes. Anemia is the primary consequence of iron deficiency. Excess iron levels can enlarge the liver, may provoke diabetes and cardiac falurer. The genetic disease hemochromatosis results from excess iron absorption. Similar symptoms can be produced through excessive transfusions required for the treatment of other diseases.
• Copper (Cu)
  Contained in enzymes of the ferroxidase (ceruloplasmin?) system which regulates iron transport and facilitates release from storage. A structural element in the enzymes tyrosinase, cytochrome c oxidase, ascorbic acid oxidase, amine oxidases, and the antioxidant enzyme copper zinc superoxide dismutase. A copper deficiency can result in anemia from reduced ferroxidase function. Excess copper levels cause liver malfunction and are associated with genetic disorder Wilson’s Disease.
• Manganese (Mn)
  Major component of the mitochondrial antioxidant enzyme manganese superoxide dismutase. A manganese deficiency can lead to improper bone formation and reproductive disorders. An excess of manganese can lead to poor iron absorption.
• Iodine (I)
  Required for production of thyroxine which plays an important role in metabolic rate. Deficient or excessive iodine intake can cause goiter (an enlarged thyroid gland).
• Zinc (Zn)
  Important for reproductive function due to its use in FSH (follicle stimulating hormone) and LH (leutinizing hormone). Required for DNA binding of zinc finger proteins which regulate a variety of activities. A component of the enzymes alcohol dehydrogenase, lactic dehydrogenase carbonic anhydrase, ribonuclease, DNA Polymerase and the antioxidant copper zinc superoxide dismutase. An excess of zinc may cause anemia or reduced bone formation.
• Selenium (Se)
  Contained in the antioxidant enzyme glutathione peroxidase and heme oxidase. Deficiency results in oxidative membrane damage with different effects in different species. Human deficiency causes cardiomyopathy (heart damage) and is known as Keshan’s disease.
• Fluorine (Fl)
  Fluorine is essential for the maintenance of solidity of our bones. Fluorine can also protect us from dental decay
• Cobalt (Co)
  Contained in vitamin B12. An excess may cause cardiac failure.
• Molybdenum (Mo)
  Contained in the enzyme xanthine oxidase. Required for the excretion of nitrogen in uric acid in birds. An excess can cause diarrhea and growth reduction.
• Chromium (Cr)
  A cofactor in the regulation of sugar levels. Chromium deficiency may cause hyperglycemia (elevated blood sugar) and glucosuria (glucose in the urine).—

Minerals are mainly extracted by mining, drilling or quarrying.
Mining: The process of taking out minerals from rocks buried under the earth’s surface is called mining. Mining are of two types:

1. Opencast mining: Open cast mining refers to the method of extraction in which minerals lying at shallow depths are taken out by removing the surface layer.
2. Shaft mining: Shaft mining refers to the method of extraction in which deep bores called shafts, have to be made to reach mineral deposits that lie at great depths.

Drilling: Deep wells are bored to take minerals out, is called drilling. 
Quarrying: In the process of quarrying, minerals that lie near the surface are simply dug out.

(i) Seeds should be grown at proper depth.
(ii) They should be sown at a proper distance apart from each other.
(iii) Seed used for sowing should be clean, healthy and free from any disease or infection.

Baking soda is a substance added in food for its faster cooking. Its chemical name is sodium hydrogencarbonate.

Sodium hydrogencarbonate is produced on large scale by reacting a cold and concentrated solution of sodium chloride with ammonia and carbon dioxide.

All plastics are polymers.

All plastics are polymers.

i. Moat or pulley-system: It is a manual irrigation method. By this method water is directly taken out of wells with the help of pulley and is used to irrigate fields.

ii. Chain pump: A chain pump consists of two large wheels, connected by an endless chain. The bottom wheel is half immersed in the water source. As the wheel is turned, the connected buckets dip into the pool and pick up water. The chain then lifts them to the upper wheel, where the water from the buckets is transferred to the pool. The chain then carries the empty buckets back down to be refilled and the process continues.

iii. Dhekli: In this system a rope and bucket connected to pole to obtain water from well. They connect rope and bucket on one end of a heavy stick and a heavy counter weight at the other end.

Coal was formed by the decomposition of large land plants and trees buried under the earth millions of years ago. It is believed that millions of years ago, due to earthquakes and volcanoes, etc., the forests were buried under the surface of the earth and got covered with sand, clay and water. Due to high temperature and high pressure inside the earth, and in the absence of air, wood was converted into coal.

Gravitation is the attractive force existing between any two objects that have mass. The force of gravitation pulls objects together.

Gravity is the gravitational force that occurs between the earth and other bodies. Gravity is the force acting to pull objects toward the earth. 

Since gravitational force is happening to all matter (objects) in the universe, from the largest galaxies down to the smallest atoms, it is often called universal gravitation. Sir Isaac Newton was the first to fully recognize that the force holding any object to the earth is the same as the force holding the moon, the planets, and other heavenly bodies in their orbits. According to Newton 's law of universal gravitation any two masses in the universe attract each other with a gravitational pull. The size of this force is given by 

f=gmM/r²

where
f is force
g is acceleration due to gravity
m and M are masses of the bodies.
r is distance between the bodies or radius of the body accordingly.

Plant -like organisms that do not contain chlorophyll are called fungi. Fungi may be unicellular (Yeast) or multicellular (Bread mould) and are found in warm and moist places. Fungi can be heterotrophic, saprophytic or parasitic in nutrition.
Examples: Yeast, Rhizopus (Bread mould), mushrooms, puffballs.