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CHEMICAL COMPOSITION OF THE BODY
CHEMICAL
COMPOSITION OF THE
BODY
ATOMS, IONS AND BONDS:
The study of physiology requires some familiarity with the basic concepts and terminology of
chemistry. A knowledge of atomic and molecular structure, the nature of chemical bonds, and
the nature of pH and associated concepts provides the foundation for much of human
physiology. The structures and physiological processes of the body are based, to a large
degree, on the properties and interactions of atoms, ions, and molecules. Water is the major
constituent of the body and accounts for 60% to 70% of the total weight of an average adult. Of
this amount, two-thirds is contained within the body cells, or in the intracellular compartment;
the remainder is contained in the extracellular compartment, a term that refers to the blood
and tissue fluids. Dissolved in this water are many organic molecules (carbon-containing
molecules such as carbohydrates, lipids, proteins, and nucleic acids), as well as inorganic
molecules and ions (atoms with a net charge). Before describing the structure and function of
organic molecules within the body.
ATOMS:
Atoms are the basic building blocks of matter. They are made up of three types of subatomic
particles: protons, neutrons, and electrons. Protons have a positive charge, neutrons have no
charge, and electrons have a negative charge.
The number of protons in an atom's nucleus determines what element the atom is, and the
number of electrons determines its chemical properties. Atoms can bond together to form
molecules through a variety of chemical reactions, which underlie many of the physical and
biological processes in the world around us.
MASS NUMBER:
The mass of a proton is equal to the mass of a neutron and the sum of the protons and
neutrons in an atom is the mass number of the atom.
ATOMIC NUMBER:
The numbers of protons in an atom is called atomic number.
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CHEMICAL COMPOSITION OF THE BODY
ISOTOPES:
1. Isotopes are variants of a chemical element that have the same number of protons in
their nucleus but different numbers of neutrons. This means that isotopes of the same
element have the same atomic number but different atomic masses.
2. Isotopes are atoms of the same element that have different numbers of neutrons in
their nucleus. This leads to differences in the atomic mass of the isotopes, but they
share the same number of protons and electrons. Isotopes can be either stable or
unstable, with unstable isotopes undergoing radioactive decay over time.
COVALENT BONDS
Covalent bonds are formed by atoms that share electrons. They are the strongest type of
chemical bond.
1. Electrons are equally shared in nonpolar covalent bonds and unequally shared in polar
covalent bonds.
2. Atoms of oxygen, nitrogen, and phosphorus strongly attract electrons and become
electrically negative compared to the other atoms sharing electrons with them.
IONIS BONDS:
Ionic bonds are formed by atoms that transfer electrons. These weak bonds join atoms
together in an ionic compound.
1. If one atom in this compound takes an electron from another atom, it gains a net negative
charge and the other atom becomes positively charged.
2. Ionic bonds easily break when the ionic compound is dissolved in water. Dissociation of the
ionic compound yields charged atoms called ions.
HYDROGEN BOND:
When hydrogen bonds with an electronegative atom, it gains a slight positive charge and is
weakly attracted to another electronegative atom. This weak attraction is a hydrogen bond.
ACIDS, BASES AND PH:
Acids donate hydrogen ions to solution, whereas bases lower the hydrogen ion concentration
of solution.
1. The pH scale is a negative function of the logarithm of the hydrogen ion concentration
2. In a neutral solution, the concentration of H+ is equal to the concentration of OH, and the pH
is 7.
MADE BY MASHAL NADEEM
CHEMICAL COMPOSITION OF THE BODY
CHEMICAL
COMPOSITION OF THE
BODY
ATOMS, IONS AND BONDS:
The study of physiology requires some familiarity with the basic concepts and terminology of
chemistry. A knowledge of atomic and molecular structure, the nature of chemical bonds, and
the nature of pH and associated concepts provides the foundation for much of human
physiology. The structures and physiological processes of the body are based, to a large
degree, on the properties and interactions of atoms, ions, and molecules. Water is the major
constituent of the body and accounts for 60% to 70% of the total weight of an average adult. Of
this amount, two-thirds is contained within the body cells, or in the intracellular compartment;
the remainder is contained in the extracellular compartment, a term that refers to the blood
and tissue fluids. Dissolved in this water are many organic molecules (carbon-containing
molecules such as carbohydrates, lipids, proteins, and nucleic acids), as well as inorganic
molecules and ions (atoms with a net charge). Before describing the structure and function of
organic molecules within the body.
ATOMS:
Atoms are the basic building blocks of matter. They are made up of three types of subatomic
particles: protons, neutrons, and electrons. Protons have a positive charge, neutrons have no
charge, and electrons have a negative charge.
The number of protons in an atom's nucleus determines what element the atom is, and the
number of electrons determines its chemical properties. Atoms can bond together to form
molecules through a variety of chemical reactions, which underlie many of the physical and
biological processes in the world around us.
MASS NUMBER:
The mass of a proton is equal to the mass of a neutron and the sum of the protons and
neutrons in an atom is the mass number of the atom.
ATOMIC NUMBER:
The numbers of protons in an atom is called atomic number.
MADE BY MASHAL NADEEM
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CHEMICAL COMPOSITION OF THE BODY
ISOTOPES:
1. Isotopes are variants of a chemical element that have the same number of protons in
their nucleus but different numbers of neutrons. This means that isotopes of the same
element have the same atomic number but different atomic masses.
2. Isotopes are atoms of the same element that have different numbers of neutrons in
their nucleus. This leads to differences in the atomic mass of the isotopes, but they
share the same number of protons and electrons. Isotopes can be either stable or
unstable, with unstable isotopes undergoing radioactive decay over time.
COVALENT BONDS
Covalent bonds are formed by atoms that share electrons. They are the strongest type of
chemical bond.
1. Electrons are equally shared in nonpolar covalent bonds and unequally shared in polar
covalent bonds.
2. Atoms of oxygen, nitrogen, and phosphorus strongly attract electrons and become
electrically negative compared to the other atoms sharing electrons with them.
IONIS BONDS:
Ionic bonds are formed by atoms that transfer electrons. These weak bonds join atoms
together in an ionic compound.
1. If one atom in this compound takes an electron from another atom, it gains a net negative
charge and the other atom becomes positively charged.
2. Ionic bonds easily break when the ionic compound is dissolved in water. Dissociation of the
ionic compound yields charged atoms called ions.
HYDROGEN BOND:
When hydrogen bonds with an electronegative atom, it gains a slight positive charge and is
weakly attracted to another electronegative atom. This weak attraction is a hydrogen bond.
ACIDS, BASES AND PH:
Acids donate hydrogen ions to solution, whereas bases lower the hydrogen ion concentration
of solution.
1. The pH scale is a negative function of the logarithm of the hydrogen ion concentration
2. In a neutral solution, the concentration of H+ is equal to the concentration of OH, and the pH
is 7.
MADE BY MASHAL NADEEM
