Elements necessary for humans

At present there are 118 elements listed in the periodic table. Some of these elements are commonly found on the earth in the form of ores. Some are radioactive and have very short half lives. Many such elements have been synthesized in the laboratory and live for a very short time.

Human body like other things existing is made of compounds which are made from the elements. Out of these 118 only some elements are connected with the human body.

Although elements as such don’t make up the body it is the combined form that is molecules constitute the human body. But elemental composition is as follows by mass.

Oxygen: 65%

Carbon: 18%

Hydrogen: 10%

Nitrogen: 3%

Other elements: 4%

Other elements include Calcium, Potassium, Phosphorus, Sulphur, Sodium, Chlorine, Magnesium, Boron, Chromium, Cobalt, Copper,  Fluorine, Iodine, Iron, Manganese, Molybdenum, Selenium, Silicon, Tin, Vanadium and Zinc.

Although these elements are used in very minor amount, they are crucial to some body processes.

Elements can be divided into different groups according to the functions they perform.

Building Blocks

The main building blocks of the body are proteins which are synthesized from amino acids. For these elements used are Hydrogen, Carbon, Nitrogen, Oxygen, Phosphorus and Sulphur. DNA also contains these elements except Sulphur. DNA is the genetic code.


Enzymes are chemicals which are catalysts for carrying out chemical reactions like breakdown of sugars and other macro molecules. Such enzymes use some elements like Magnesium, Manganese, Copper, Zinc, Selenium and Molybdenum. Enzymes play role in respiration, digestion, metabolism and immune system.

Nerves and Control

Brain sends messages to different parts of the body and this is a two way communication. Electrical signals are carried through electrolytic solutions like brines. Sodium, Potassium and Calcium ions this play the role of transmitting the signals. Similarly Chloride ions regulate the water in and out of cells. Iodine is used to make hormones which regulate metabolism.

Bones and Teeth

Bones make the template on which our body is hoisted. Strong bones and teeth are essential for the healthy body.  Bones and Teeth are made of Calcium and phosphate. Phosphate contains Phosphorus and Oxygen. Manganese element makes more stronger and resistance to breaking.


Blood is the lifeline of the body. Blood carries oxygen to the cells and removes the carbon-dioxide gas which is the byproduct of combustion reaction. Oxygen is carried by blood due to the presence of iron which binds the Oxygen. Other elements which are constituents of blood are Carbon, Oxygen, Iron and Cobalt. Cobalt is essential to make red blood cells.

Respiration and Energy

Respiration is inhalation of Oxygen. Adinosine Triphosphate (ATP) is formed during respiration which is the compound used by body as energy. Main elements involved here are Carbon, Nitrogen, Phosphorus and Oxygen.

Source: c&en magazine of American Chemical Society (ACS)


Price Paid for Being Humans-1

It is a scientific fact that all living things evolved from the simplest single cell bacteria. These are called cyano-bacteria or green algae. They were the first harvesters of sun energy using photosynthesis and making food for themselves. Thus the food comes from the Sun.

Slowly, the life diversified, especially after the introduction of oxygen into the atmosphere thanks to these green algae. Living beings evolved which cannot make their own food like plants but use the food prepared by the plants and burn it with oxygen.

Then Darwin came and after a massive study and observations in the Canary Islands announced that higher forms of living things evolve slowly from the lower forms. This is a consequence of struggle for survival and survival rate of the fittest or the species which are capable of modifying themselves according to the environment are the best. Humans are a mere speck in this diversity majority of which is staked by the bacteria.

From water to land and from crawling to walking on four limbs, human freed their forelimbs to use them as tools and also stand upright which helps in running away from danger, following the prey and gain the greater ability to watch up to far away distances to locate the danger as well as food. But we have to pay the price for this in the form of backaches, diseases and difficult child birth.

Natural selection continuously sifts the best from the individuals of each generation. But this sometimes occurs clumsily, as old parts and genes are co-opted for new roles. As a result, all species inhabit bodies imperfect for the lives they live. Our own bodies are worse off than most simply because of the many differences between the wilderness in which we evolved and the modern world in which we live. We feel the consequences every day. Here is the first.

Our cells are weird chimeras
Multicellular life started when two cells merged and fused into one. The hunter cell swallowed the prey cell and encapsulated it. Then the prey became the mitochondrion. This is the machinery which provides the cell energy and makes possible its survival. Most of the time, this ancient symbiosis proceeds amicably.

But every so often, our mitochondria and their surrounding cells fight. The result is diseases, such as mitochondrial myopathies (a range of muscle diseases) or Leigh’s disease (which affects the central nervous system).

Other handicaps shall be discussed in subsequent posts.