2. The human body is composed of organic
molecules that participate in important processes
and chemical reactions vital to life. These
molecules are made up of particles that cannot be
seen by your unaided eyes. An atom is the smallest
particle of an element. There are 118 known types of
atoms; they constitute the chemical elements
listed in the periodic table
3.
4. There are some elements that constitute
more than 99% of the matter found in living
things. These are called bioelements. The
main bioelements that make up living
things mostly consist of carbon (C), oxygen
(O), hydrogen (H), and nitrogen (N).
5. Other bioelements found in living things
that appear in smaller quantities are
calcium, potassium, phosphorus, sulfur,
and magnesium.When bioelements are
joined, they form biomolecules.
6. Biomolecules are the building blocks of
living things. These are what living things
are made of. In the next lessons, you will
learn different biomolecules of life,
namely, carbohydrates, lipids, proteins,
and nucleic acids.
7. Biomolecules are also considered
macromolecules. These are polymers that
are built of monomers. A polymer is a long
molecule that consists of several monomers,
which are combined through covalent
bonding. A monomer is the building block of
a polymer
9. Polymers are considered complex compounds. Note
that the compounds may be expressed as an empirical
formula, which simply shows the relative number of
atoms present in it, whereas the structural formula
shows the bonding between atoms through a graphical
arrangement. As these arrangements vary, they also
affect the nature and properties of the organic
compounds.
13. Carbon (C) is an essential element of any living
matter. There is 0.09% by mass of carbon present
in Earth’s crust. Carbon occurs in different forms. It
is found freely in nature as diamond, graphite, or
components of natural gas, petroleum, and coal
that can be derived from the remains of dead
organisms million years ago.
14. Carbon has the unique ability to form long chains.
This ability makes carbon suitable to form many
different shapes of complex organic compounds.
These complex organic compounds make up the
bodies of organisms. Carbohydrates, lipids, proteins,
and nucleic acids contain carbon. This means that
carbon can be found in all parts of all living things
16. Oxygen is the most abundant element in
Earth’s crust,
constituting 46% by mass and 23% by mass in
the atmosphere. Oxygen is also one of the
biomolecules found in organisms. Oxygen in its
molecular form (O2) is an important oxidant to
break down food molecules.
17. Humans cannot survive for more than a
few minutes without oxygen.Oxygen exists
as a diatomic molecule in the free state. It
is present in all forms of biomolecules,
namely, carbohydrates, lipids, proteins,
and nucleic acids
19. Nitrogen is the most abundant element in Earth’s
atmosphere, comprising 78% by volume. Nitrogen is
an essential component found in proteins and nucleic
acids. Nitrogen is found in amino acids, which are the
building blocks of proteins. In nucleic acids, nitrogen
is part of the nitrogenous base, which is an organic
molecule containing both carbon and hydrogen.
21. Hydrogen is the simplest element known, having
one proton and one electron. It is the 10th most
abundant element in Earth’s crust. In its free state,
hydrogen exists as a diatomic molecule. It is an
essential component of the three major
biomolecules, namely, carbohydrates, proteins,
and nucleic acids.
