FIRST QUARTER MODULE 6

BIOLOGICAL
MACROMOLECULES
Physical Science– Grade 11/12
Quarter 1 – Module 6: Biological Macromolecules

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Regional Director: Gilbert T. Sadsad

Assistant Regional Director: Jessie L. Amin

Development Team of the Module

Writer: Rommel Carl R. Peralta

Illustrator: Ray Daniel Peralta

Layout Artist: Jose Gamas Jr.

Language Editor: Diana Desuyo

Editors/ Reviewers: Jocelyn Navera

Kristina Nieves
Brenly Mendoza
Bevelyn Nocomora

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Explain how the structures of biological
macromolecules such as
carbohydrates, lipids, nucleic acid and
proteins determine their properties and
functions
(S11/12PS-IIIe-22)

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 Supplementary Learning Module for Senior High School Learners

LESSON
BIOLOGICAL MACROMOLECULES

In the previous grade level, you understood

that living matter is made mostly of carbon, oxygen,
hydrogen and nitrogen with some sulfur and
phosphorous. Biological diversity has its molecular
basis in carbon’s ability to form huge number of
molecules with particular shapes and chemical
properties. In this module, you will know the critical
role of the biological macromolecules in cell
structure and function.

Nutrients are the molecules needed by

living organisms to survive and grow however
animals and plants cannot synthesize themselves.
Animals gain nutrients by consuming food, while
plants pull nutrients from soil. Hence many
critical nutrients are biological macromolecules.
Do you want to know these biological
macromolecules? Read on and accomplish the
tasks prepared for you in this module.

At the end of the module, you should be

able to:

• identify the four types of biological

marcomolecules; and
• explain how the structures of biological
macromolecules such as carbohydrates, lipids,
nucleic acid and proteins determine their
properties and functions.

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 Directions: Choose the letter of the correct answer.

1. Which of the following macromolecules serve as fuel and building material of

the body?
a. Carbohydrates
b. Protein
c. Lipids
d. Nucleic Acid

2. What do you call the relatively large molecule consisting of a chain or network
of many identical or similar monomers chemically bonded to each other?
a. Enzymes
b. Polymer
c. Amylose
d. Ribose

3. Which of the following is NOT a type of biological macromolecule?

a. Carbohydrates
b. Protein
c. Nucleic Acid
d. Iron

4. What example of protein has a function of catalysing a chemical reaction?

a. Hormones
b. Receptor Protein
c. Transport Protein
d. Enzyme

5. What biological macromolecule that store, transmit, and help express

hereditary information?
a. Carbohydrates
b. Protein
c. Nucleic Acid
d. Iron

Hi! How did you find the test?

Please check your answers at the answer key

section and see how you did. Don’t worry if you got a low
score, this just means that there are more things that
you can learn from this module. So, hop on!

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 JUMBLED LETTERS

Below are jumbled words about biological

macromolecules. Arrange the letters and
match it to its description.

1. These are polymers built from monomers

2. It includes both sugar and polymers of sugar

3. It is a diverse group of hydrophobic molecules

4. It store, transmit and help express hereditary information.

5. It includes a diversity of structures resulting in a wide range of functions

CHOICES

SIPLID ORPNTEI CUMACMOORLELE

LEINCCU IDCA YHCBODRATESAR

Good job in finishing the activity! Take note of the key concepts you had
written. These words might appear on the next activities.

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 BIOLOGICAL MACROMOLECULES

With the rich complexity of life on Earth, you can expect that all living
organisms have enormous diversity of molecules. From bacteria to whale, there are
large molecules that provide the basic necessities in order these living organisms to
survive. Carbohydrates, lipids, proteins and nucleic acid are the four types of
biological macromolecules that play vital role in building material, storing,
transmission and hereditary information.
The macromolecules in three of the four classes of life’s organic compounds-
carbohydrates, proteins, and nucleic acids- are chain-like molecules called polymers
(from the Greek polys, many and meros, part). A polymer is a long molecule
consisting of many similar or identical building blocks linked by covalent bonds,
much as a train consists of chain cars. The repeating units that serve as the building
blocks of a polymer are smaller molecules called monomers (from the Greek monos,
single). Some of the molecules that serve as monomers also have other functions of
their own.
Each cell has thousands of different macromolecules; the collection varies
from one type of cell to another even in the same organism. The inherent differences
between human siblings reflect small variations in polymers, particularly DNA and
proteins.
Despite this immense diversity, molecular structure and function can still be
grouped roughly by class. These four major classes of large biological molecules
have emergent properties not found in their individual building blocks.

CARBOHYDRATES
The word carbohydrate may be broken down to carbon and hydrate. From the
chemical formula of carbohydrate, notice that the ratio of C:H:O is 1:2:1, which can
be rewritten as Cn(H2O)n. Carbohydrates can be seen as hydrates of carbon. This is
a traditional but incorrect understanding of carbohydrates but it still presents a useful
picture of the molecule. Another term for carbohydrate is saccharide. This term is
derived from the Latin word saccharum referring to sugar--a common carbohydrate.
Carbohydrates are classified either as simple or complex. Simple sugars are
monosaccharides and disaccharides. Complex sugars are polysaccharides.

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 Carbohydrates are the primary energy source of the human body. The
different saccharides that humans eat are converted to glucose which can be readily
used by the body. Around 4 kilocalories is derived from one gram of carbohydrate.
Should there be an excessive consumption of carbohydrates, the excess is
converted to glycogen which is stored in the liver and in muscles. Glycogen is a
slow-releasing carbohydrate.
Examples of monosaccharide (one saccharide) are:
• Glucose -used in dextrose, blood sugar; the form utilized by the
human body
• Galactose -found in milk and milk products
• Fructose -found in fruits and honey

The above monosaccharides all have the same chemical formula of C6H12O6
and its structure is the one that made the difference in its properties. For example,
galactose (163-169oC) has a higher melting point than glucose (148-155oC). Glucose
is sweeter than galactose.
On the other hand, examples of Disaccharide (two saccharides) are:
• Maltose - Glucose + Glucose Found in malt
• Sucrose - Glucose + Fructose Found in regular table sugar,
sugarcane, and sugar beet
• Lactose - Glucose + Galactose Found in milk and milk
products
Individual saccharides are connected via glycosidic bonds. A water molecule
is released when two saccharides are combined.
The examples of Polysaccharide (many saccharides) are:
Starch / Amylose - Composed of 250 - 400 glucose molecules connected
via α-1-4- glycosidic bond. It is a storage form of
glucose in plants
Amylopectin - Like amylose but has more branches attached via α-1-6
glycosidic bond. It is a storage form of glucose in
plants
Glycogen -Composed of more glucose, more highly branched
(same type of bond as amylopectin) . It is storage
form of glucose in animals, stored in the liver and
muscles
Cellulose -Composed of glucose units connected via β-1-4 glycosidic
bond, linear chain arranged in a parallel manner . It is
a structural material in plants--cell wall in wood, wood
fiber cannot be digested by humans

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STRUCTURES OF CARBOHYDRATES

MONOSACCHARIDES

DISACCHARIDES

POLYSACCHARIDES

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PROTEIN
The word protein came from the Greek term “proteios” meaning first. One can
think of protein as the beginning of life. From egg albumin being pure protein to
sperm and egg cells, we all start from proteins. Proteins are composed of four
elements, namely, carbon, hydrogen, oxygen and nitrogen. Sulfur and other metals
are sometimes also found in proteins. If carbohydrates are made up of saccharides,
proteins are made up of amino acids. An amino acid is a molecule that has an amine
and a carboxyl group.
There are 20 amino acids. The combination of many amino acids creates
protein. Amino acids are joined together with a peptide bond. Proteins are also called
polypeptides.
The diagram below shows that water is released in the formation of peptide
bonds. This is similar to the formation of complex saccharides.

Different types of proteins are composed of different combinations of amino

acids arranged in a specific way. Depending on the order of the amino acids, the
protein will acquire a certain configuration and function. The configuration is
governed by several factors, namely:
a. H-bonding between amino acids which creates either a helical structure or
a pleated sheet
b. Disulfide bonds for amino acids containing sulfur
c. Salt bridges
d. Hydrophobic and hydrophilic tendencies

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 There are different examples of proteins. These are:
• Keratin. It is a structural protein found in hair, skin, and nails. It is a highly
cross-linked protein containing α-helix and β-pleated sheets. Sheep’s wool
is made largely of keratin.

• Fibroin. It is found in silk. Silk has a smooth and soft texture. It is one of
the strongest natural fibers that have high resistance to deformation. It is
also a good insulation. Silk is primarily composed of β-pleated sheets. The
long polypeptide chain doubles back on its own running parallel connected
together by H-bonds.

• Collagen. It is a major insoluble fibrous protein found in connective tissues

such as tendons, ligaments, skin, cartilage and the cornea of the eye. It
comprises as much as 30% of proteins in animals. Its strength is attributed
to its triple helix structure comprising of α-helices braided together. When
several triple helices combine, they form the fibrils that make up connective
tissues

• Enzymes. It functions to catalyze chemical reactions. They either speed up

a reaction, lower the needed energy for a reaction to take place, or bind
substances to their specific partners. Enzymes themselves are very specific
as can be seen in their shape. Examples of enzymes are: (1) Lipase - help
in digestion of fats; (2) Pepsin - help in breaking down proteins into
peptides (smaller units); (3) Sucrase - also called invertase, help in the
digestion of sugars and starches.

• Myoglobin. It is a polypeptide that stores oxygen in muscles. It is a

globular protein comprised of 153 amino acids in a single polypeptide
chain. It contains a heme group which has an iron (II) ion at its center. This
is where the oxygen is stored.

• Hemoglobin. It is a globular protein that carries oxygen from the lungs to

the bloodstream. It is composed of four sub-units, each containing a heme
group that enables it to transport four oxygen molecules at a time.

LIPIDS
The word lipid comes from the Greek word “lipos” which means fat. Lipids are
a family of biomolecules having varied structures. They are grouped together simply
because of their hydrophilic property (water-fearing). They are soluble in non-polar
solvents such as ether, acetone, and benzene. Lipids can be classified into four
categories: a. Wax; b. Triglycerides; c. Phospholipids; and d. Steroids. Examples of
Lipids are:
• Fatty acids. It is essential to understanding lipids. Fatty acids are long-
chain carboxylic acids that are insoluble in water. Fatty acids can be

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 saturated or unsaturated. Saturated fatty acids contain single bonds in its
hydro-carbon chain whereas unsaturated fatty acids contain double bonds.
An easy way to remember saturated fatty acids is to think of them as
“saturated” with hydrogen. All the carbon molecules have two hydrogen
atoms attached to it. In unsaturated fatty acids, carbons with a double bond
only have one hydrogen atom attached to it hence being “unsaturated.”
Saturated fatty acids allow their molecules to fit close together and form
strong attraction. They usually have high melting points and are solid at
room temperature. Unsaturated fatty acids are bent because of the double
bond and are therefore, not as close together as saturated fatty acids. They
are often irregularly shaped. Unsaturated fatty acids have a low melting
point and are liquid at room temperature. Lipids containing either saturated
or unsaturated fatty acids somehow are able to retain these properties.

• Triglyceride Fat and oil are the most common examples of lipids. They
are under triglycerides because they are composed of glycerol and three
fatty acids.

• Fat refers to solid triglyceride usually from animal sources such as meat,
milk, butter, margarine, eggs, and cheese. Oil refers to liquid triglycerides
from plant sources. Examples are olive oil, corn oil, sunflower oil, and
soybean oil. Animal fat contains high percentages of saturated fatty acids
while plant oil is mostly unsaturated fatty acids.

• Phospholipids contain glycerol, two fatty acids, and a phosphate group.

Unlike other lipids, phospholipids have a polar and non-polar end. This
property allows it to transport molecules in the bloodstream. It is also a
major component in the cell membrane. The two parts of a phospholipid
can be termed as the hydrophilic head (phosphate group) and hydrophobic
tail (fatty acid group). This dual property allows phospholipids to form a
phospholipid bilayer. In this configuration, the hydrophilic head sticks out
while the hydrophobic tail is tucked in and away from the watery
environment. This is why phospholipids are suitable as cell membrane.

NUCLEIC ACID
Nucleic acids play an essential role in the storage, transfer, and expression of
genetic information. Nucleic acid was discovered by a twenty-fouryear-old Swiss
physician named Friedrich Miescher in 1868. He was puzzled that an unknown
substance in white blood cells did not resemble carbohydrates, proteins, or lipids. He
was able to isolate the substance from the nucleus and initially called it nuclein. He
eventually was able to break down nuclein into protein and nucleic acids. He found
out that nucleic acids contain carbon, hydrogen, oxygen, nitrogen, and phosphorus.
The most common examples of nucleic acids are DNA (deoxyribonucleic acid)
and RNA(ribonucleic acid). DNA is a nucleic acid that carries the genetic code of

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organisms. It is fondly termed as the blueprint of life. RNA, on another hand, carries
the information from the DNA to the cellular factories for the synthesis of proteins. If
carbohydrates are composed of saccharide units, proteins of amino acids, and lipids
of fatty acids, nucleic acids are composed of nucleotides. Nucleic acids are also
known as polynucleotides. A nucleotide has three parts: a. Nitrogenous base; b.
Five-carbon carbohydrate or sugar; and c. Phosphate group
The nitrogenous bases of DNA and RNA are: DNA’s : Adenine (A), Guanine
(G), Cytosine (C), and Thymine (T) RNA’s : Adenine (A), Guanine (G), Cytosine (C),
and Uracil (U). DNA has a different sugar group than RNA. DNA has deoxyribose
while RNA has ribose.

The drawing above shows that DNA is double stranded and RNA is single
stranded. The bases are paired up as can be seen in DNA. The bases C and G have
three H-bonds between them, and A and T have two. Hydrogen bonding is greatly
responsible for the shape of both RNA and DNA. The different nucleotides are
connected in a chain via phosphodiester bonds.
The sequence of the base pairs in one’s DNA is unique for every organism
(except for identical twins). The DNA and the cell containing it determine the kind of
protein that will be synthesized. The different proteins are then responsible for the
processes that carbohydrates, lipids, proteins, and other substances in the body
undertake.

Source: Commission on Higher Education,

Teaching Guide for Senior High School Physical Science

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DIRECTIONS: Summarize your learning by filling-up the table below.

Biological Elements Found Function Example

Macromolecule in the Molecule
Carbohydrates

Protein

Lipids

Nucleic Acid

Directions: Answer the following questions.

1. What are the four types of biological marcomolecules?

2. How do the structures of biological macromolecules such as
carbohydrates, lipids, nucleic acid and proteins determine their
properties and functions?

Directions: Make a poem describing the importance of biological macromolecules to our

lives. You will be graded using the rubric below.

• Content - 50%
• Creativity - 30%
• Accuracy of Information - 20%
TOTAL 100%

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 Discuss the benefits of products or technologies that uses carbohydrates, protein,
lipids and nucleic acid. Show your answer by using a concept map.

The following terms used in this module are defined as follows:

CARBOHYDRATES. It includes both sugar and polymers of sugar.

LIPIDS. It is a diverse group of hydrophobic molecules.

MACROMOLECULE. These are polymers built from monomers.

MONOMER. These are repeating units that serve as the building blocks of a
polymer.
NUCLEIC ACID. It store, transmit, and help express hereditary information.

POLYMER. It is a long molecule consisting of many similar or identical building

blocks linked by covalent bonds.
PROTEIN. It includes a diversity or structures resulting in a wide range of functions.

Great! You have completed your learning

episodes in this module!

You are now ready to start a new

learning adventure in the next module.

Congratulations!

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TRY THIS
1) a 2) b 3) d 4) d 5) c

DO THIS: Jumbled Letters

1) MACROMOLECULE
2) CARBOHYDRATES
3) LIPIDS
4) NUCLEIC ACID
5) PROTEIN

What You Have Learned

Biological Elements Function Foods where the

Macromolecule Found in macromolecules
the can be found
Molecule
Carbohydrates C, H, O -Primary source of energy in -Bread, rice, fruits,
the body grains, root crops,
and sugar
-Structural material in plants
Protein C, H, O, N -Structural material -Meat, dairy
-Enzyme products, nuts and
-Storage molecule egg
-Transport molecule
-Antibody
Lipids C, H, O -Source of energy Oil, butter, nuts, and
-Maintaining body heat fish
-Aid in digestion
-Material for cell membrane
-Signal molecules
Nucleic Acid C, H, O, N, -Proteinsynthesis None
P -Code of life

Assess What You Have Learned

1. Carbohydrates, Protein, Lipids and Nucleic Acid

2. All biological macromolecules are being composed of carbon, hydrogen
and oxygen however there is the presence of nitrogen in both protein and
nucleic acid. Moreover, only nuclei acid has phosphorous. The presence
these elements and their molecular structure dictates the function its
function and purpose.

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Campbell, N. & Reece, J. Campbell Biology. Ninth Edition. Pearson. USA. (2005)

Commission on Higher Education. Teaching Guide for Senior High School Physical Science.
(2016)

Timberlake, K. C. Chemistry: An Introduction to General, Organic, and Biological Chemistry

5th ed. United States of America: HarperCollins Publishers Inc. (1992)
McMurry, J. E., Fay, R. C. Chemistry 5th ed. United States of America: Pearson Prentice
Hall. (2008)
Boyer, R. Concepts in Biochemistry 3rd ed. Asia: John Wiley & Sons Inc (4) see additional
resources. (2006)

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