Elements and Compounds

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Most of us have heard something along the lines of our adult bodies are made up of about 60% water. But what does that even mean? Are just liquid contained in a solid body? What are cells? What is flesh? Aren’t we made up of proteins? What is protein? What are carbohydrates?

Most humans have an understanding that Water is a compound of mostly hydrogen and oxygen, being H2O.  When you hear this, you are referencing the body on a molecular level. Molecules are the smallest unit of measurement for two or more atoms held together by a chemical bond, wherein it is the same property of that element or compound. For an example, a “pure water” molecule is the smallest particle of matter that is still “pure water”; whereas, if you were to break it down any further then it would become two hydrogen atoms and one oxygen atom. A Carbohydrate is a molecule with a compound of hydrated carbon Cm(H2O)n, (where m may be different from n)whereas if you were break it down further to the atomic level, it would be just some variation of Carbon, Hydrogen, and Oxygen atoms.  A glucose molecule is atomic chemical bond of C6H12O6, whereas if you were break it down further to the atomic level, it would be just 6 Carbon atoms, 12 Hydrogen atoms, and 6 Oxygen atoms. The Earth’s atmosphere contains Oxygen molecules, being two or more Oxygen atoms, hence the O2 molecules we breathe in and the Ozone layer being molecules of O3.  We do not eat or consume pure elements or atoms, but a molecular compound, i.e. water, which isn’t pure H2O as there are other mineral particles bonded together in the water molecule we drink but more on that on water page.

So Molecules (two or more atoms) are combinations of the Elements (single atoms). The Elements are single atoms of matter, but atoms are made up of protons, neutrons and electrons. How many protons an atom has determines what element it is. Hydrogen has one proton and one electron. Carbon has 6 protons and 6 electrons. Oxygen has 8 protons and 8 electrons.  

Having a understanding of that will help one better understand the composition of the human body on a atomic and molecular scale, along with the foods we eat and how each are unique and different. 

We are taught by science that Matter is anything that has mass and takes up space by having volume. 

According to the lesson on Matter, Elements and Atoms on Khanacademy.org, 

“Atoms and molecules follow the rules of chemistry and physics, even when they're part of a complex, living, breathing being. If you learned in chemistry that some atoms tend to gain or lose electrons or form bonds with each other, those facts remain true even when the atoms or molecules are part of a living thing. In fact, simple interactions between atoms—played out many times and in many different combinations, in a single cell or a larger organism—are what make life possible. One could argue that everything you are, including your consciousness, is the byproduct of chemical and electrical interactions between a very, very large number of nonliving atoms!

So as an incredibly complex being made up of roughly 7,000,000,000,000,000,000,000,000,000 atoms, you'll probably want to know some basic chemistry as you begin to explore the world of biology, and the world in general.

All matter is made up of substances called elements, which have specific chemical and physical properties and cannot be broken down into other substances through ordinary chemical reactions. Gold, for instance, is an element, and so is carbon. There are 118 elements, but only 92 occur naturally. The remaining elements have only been made in laboratories and are unstable… 

The four elements common to all living organisms are oxygen (O), carbon (C), hydrogen (H), and nitrogen (N), which together make up about 96% of the human body. In the nonliving world, elements are found in different proportions, and some elements common to living organisms are relatively rare on the earth as a whole. All elements and the chemical reactions between them obey the same chemical and physical laws, regardless of whether they are a part of the living or nonliving world.”

Some people look at the world in a very material way and think of their physical body as just flesh and bones of the animal kingdom, having the organs and systems of mammals. Some people look deeper and view our bodies at the cellular level having trillions of cells that are programmed to perform automated tasks for the organs and systems to function properly. Some people go deeper and see our bodies as a molecular structure made up of about 60% water. Some people go even deeper and view our bodies as structural representations of the original Atom elements. Some people view our bodies as shells to the energy, ethereal or spiritual realm, and connect energy with matter. Let’s break it all down on a atomic, molecular, and material tissue scale so there’s a better understanding of our bodies.

Major Classes of Compounds in the Human Body

Most of the elements are found within compounds. Water and minerals are inorganic compounds. Organic compounds include fat, protein, carbohydrates, and nucleic acids.

• Water: Water is the most abundant chemical compound in living human cells, accounting for 65 percent to 90 percent of each cell. It's also present between cells. For example, blood and cerebrospinal fluid are mostly water.

• Fat: The percentage of fat varies from person to person, but even an obese person has more water than fat.

• Protein: In a lean male, the percentages of protein and water are      comparable. It's about 16 percent by mass. Muscles, including the      heart, contain a lot of muscle. Hair and fingernails are protein. Skin      contains a large amount of protein, too.

• Minerals: Minerals account for about 6 percent of the body. They include salts and metals. Common minerals include sodium, chlorine, calcium, potassium, and iron.

• Carbohydrates: Although humans use the sugar glucose as an energy source, there isn't that much of it free in the bloodstream at any given time. Sugar and other carbohydrates only account for about 1% of body mass.

All the food that we eat is a chemical compound. Our bodies are chemical compounds.

Also notice how the body has its own response and reaction regarding how it utilizes the different categories. 

According to the Wikipedia page, “Composition of the human body”

"The average 70 kg (150 lb) adult human body contains approximately 7×1027 atoms and contains at least detectable traces of 60 chemical elements. About 29 of these elements are thought to play an active positive role in life and health in humans. 

The relative amounts of each element vary by individual, mainly due to differences in the proportion of fat, muscle and bone in their body. Persons with more fat will have a higher proportion of carbon and a lower proportion of most other elements (the proportion of hydrogen will be about the same).”

Molecules

The composition of the human body is expressed in terms of chemicals:

· Water

· Proteins – including those of hair, connective tissue, etc.

· Fats (or lipids)

· Hydroxyapatite in bones

· Carbohydrates such as glycogen and glucose

· DNA

· Dissolved inorganic ions such as sodium, potassium, chloride, bicarbonate, phosphate

· Gases such as oxygen, carbon dioxide, nitrogen oxide, hydrogen, carbon monoxide, acetaldehyde, formaldehyde, methanethiol. These may be dissolved or present in the gases in the lungs or intestines. Ethane and pentane are produced by oxygen free radicals.[36]

· Many other small molecules, such as amino acids, fatty acids, nucleobases, nucleosides, nucleotides, vitamins, cofactors.

· Free radicals such as superoxide, hydroxyl, and hydroperoxyl.

The circulatory system consists of the heart and blood vessels (arteries, veins and capillaries). The heart propels the circulation of the blood, which serves as a "transportation system" to transfer oxygen, fuel, nutrients, waste products, immune cells and signalling molecules (i.e. hormones) from one part of the body to another. Paths of blood circulation within the human body can be divided into two circuits: the pulmonary circuit, which pumps blood to the lungs to receive oxygen and leave carbon dioxide, and the systemic circuit, which carries blood from the heart off to the rest of the body. The blood consists of fluid that carries cells in the circulation, including some that move from tissue to blood vessels and back, as well as the spleen and bone marrow.

The endocrine system consists of the principal endocrine glands: the pituitary, thyroid, adrenals, pancreas, parathyroids, and gonads, but nearly all organs and tissues produce specific endocrine hormones as well. The endocrine hormones serve as signals from one body system to another regarding an enormous array of conditions, and resulting in variety of changes of function.

The nervous system consists of the body's neurons and glial cells, which together form the nerves, ganglia and gray matter which in turn form the brain and related structures. The brain is the organ of thought, emotion, memory, and sensory processing; it serves many aspects of communication and controls various systems and functions. The special senses consist of vision, hearing, taste, and smell. The eyes, ears, tongue, and nose gather information about the body's environment.

From a structural perspective, the nervous system is typically subdivided into two component parts: the central nervous system (CNS), composed of the brain and the spinal cord; and the peripheral nervous system (PNS), composed of the nerves and ganglia outside the brain and spinal cord. The CNS is mostly responsible for organizing motion, processing sensory information, thought, memory, cognition and other such functions. It remains a matter of some debate whether the CNS directly gives rise to consciousness. The peripheral nervous system (PNS) is mostly responsible for gathering information with sensory neurons and directing body movements with motor neurons.

From a functional perspective, the nervous system is again typically divided into two component parts: the somatic nervous system (SNS) and the autonomic nervous system (ANS). The SNS is involved in voluntary functions like speaking and sensory processes. The ANS is involved in involuntary processes, such as digestion and regulating blood pressure.

The nervous system is subject to many different diseases. In epilepsy, abnormal electrical activity in the brain can cause seizures. In multiple sclerosis, the immune system attacks the nerve linings, damaging the nerves' ability to transmit signals. Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a motor neuron disease which gradually reduces movement in patients. There are also many other diseases of the nervous system.

The respiratory system consists of the nose, nasopharynx, trachea, and lungs. It brings oxygen from the air and excretes carbon dioxide and water back into the air. First, air is pulled through the trachea into the lungs by the diaphragm pushing down, which creates a vacuum. Air is briefly stored inside small sacs known as alveoli (sing.: alveolus) before being expelled from the lungs when the diaphragm contracts again. Each alveolus is surrounded by capillaries carrying deoxygenated blood, which absorbs oxygen out of the air and into the bloodstream.

For the respiratory system to function properly, there need to be as few impediments as possible to the movement of air within the lungs. Inflammation of the lungs and excess mucus are common sources of breathing difficulties. In asthma, the respiratory system is persistently inflamed, causing wheezing and/or shortness of breath. Pneumonia occurs through infection of the alveoli, and may be caused by tuberculosis. Emphysema, commonly a result of smoking, is caused by damage to connections between the alveoli.

The urinary system consists of the kidneys, ureters, bladder, and urethra. It removes toxic materials from the blood to produce urine, which carries a variety of waste molecules and excess ions and water out of the body.