Biological Macromolecules

Biological Macromolecules

Lesson Essential Questions:

What are biological macromolecules? What are macromolecules made of? How do living things use macromolecules? How is the expression, “You are what you eat,”

relevant to the study of macromolecules?

What are biological macromolecules?

Biological Macromolecules

large molecules essential for life (macro=large) organic = carbon-based

carbon is the building block of ALL life

Four Groups of Macromolecules

CARBOHYDRATES

LIPIDS

NUCLEIC ACIDS

PROTEINS

DNA

What are they made of? What is their structure?

Biological Macromolecules

macromolecules are polymers polymers are made of repeating subunits each subunit (building block) is called a monomer

Monomers

to form a Polymer

join together through polymerization

Biological Macromolecules

monomers are joined together through a chemical reaction called dehydration synthesis to form polymers

when chemical bonds between monomers form, a water molecule is lost “dehydration”

How do monomers join together to make a polymer?

Four Groups of Macromolecules

CARBOHYDRATES

LIPIDS

NUCLEIC ACIDS

PROTEINS

DNA

Carbohydrates Composition: Carbon, Hydrogen, & Oxygen atoms (CHO)

in a 1:2:1 ratio (e.g., C6H12O6) (ring structures)

Monomer (Building Block): Monosaccharide Polymer: Polysaccharide Functions:

1. Store energy

2. Structural components

Where Found in Organisms:1. Glycogen (short-term energy storage) in muscles & liver

2. Starch stored in fruit, seeds, & tubers of plants

3. Plant cell walls (cellulose)

4. Exoskeletons of insects and arthropods & cells walls of fungi (chitin)

Food Examples: sugars, starches, grains, fruits & veggies Fact: Provide quick energy; Common suffix is –ose (e.g., lactose)

Lipids (Fats, Oils & Waxes) Composition: Carbon, Hydrogen, & Oxygen (CHO) in

chains Building Blocks: Fatty acids & glycerol Functions:

1. Long-term energy storage (fat cells)

2. Waterproof barriers (waxes & cell membrane)

3. Chemical messengers (steroids, hormones & cholesterol)

Examples in Organisms: animal fat, beeswax, steroids, phospholipids in cell membranes

Food Examples: oils, butter, lard Fact: lipids are not water-soluble

Proteins Composition: Carbon, Hydrogen, Oxygen, & Nitrogen

(CHON) Monomer: amino acids (20 different) Polymer: polypeptide Functions: Most abundant macromolecule

in the body1. Growth & repair of tissue (e.g. muscle)

2. Structural support (e.g., hair, horns, feathers)

3. Speed up chemical reactions (enzymes)

4. Transport substances

5. Fight disease (antibodies)

Examples in Organisms: muscles, hair, fingernails, skin, Food Examples: meat, poultry, fish, beans, nuts, eggs Fact: Suffix for enzymes is –ase (e.g., lactase)

Nucleic Acids Composition: Carbon, Hydrogen, Oxygen, Nitrogen, &

Phosphorus (CHONP) Monomer: nucleotide Polymer: polynucleotide Functions:

1. Store & transmit genetic information

2. Regulate synthesis of proteins Examples: DNA and RNA Fact: We do not get nucleic acids from foods. We build

them in our cells using molecules from other digested macromolecules.

You Are What You EatYou eat food containing proteins, carbohydrates, and fats (lipids).

You Are What You EatThe macromolecules in the food are broken down by the digestive system into smaller molecules by mechanical processes and by enzymes.

You Are What You EatThese small molecules are absorbed into the bloodstream through the intestines and delivered to cells throughout the organism.

You Are What You EatThey transport into cells and undergo chemical reactions to break down into their component parts.

Molecules transported into a cell

polymers are broken down through a chemical reaction called hydrolysis to form monomers

a water molecule is required to break each chemical bond between monomers “hydrolosis”

Reverse of

dehydration synthesis

How are polymers broken down into monomers?

You Are What You Eat

You Are What You EatOnce inside the cell, these molecules can be building blocks for new macromolecules used for cell structure and processes.

Inside the cell: Assembling new proteins from amino acids

Check Your Understanding

1. What does organic mean?

2. What one element is essential for all life on Earth?

3. What other elements are used to make macromolecules?

4. Name the building blocks (monomers) of

a. Carbohydrates

b. Lipids

c. Proteins

d. Nucleic acids

5. By what process are monomers joined together to make polymers?

6. What would you eat for quick energy? to build muscle?

7. Which types of macromolecules in in –ose? –ase?