M1A: Topic 4 - Biomolecules

Examples of Carbohydrates:

Sugar

Starch

Glycogen

Cellulose

Chitin

Examples of Lipids:

Fats

Sterols/Steroids

Phospholipids

Examples of Proteins:

Enzymes

Muscle

Transport

Receptors

Examples of Nucleic Acids

DNA

RNA

All about the Biomolecule structure:

Carbon

Carbohydrates, proteins, and nucleic acids can form polymers from monomers

Lipids are assembled from smaller components but are not true polymers

Carbohydrates are..

saccharides (sugar)

What are monomers?

Monosaccharides

What are polymers?

Polysaccharides

What bond is held between carbohydrates?

Glycosidic bond

What are the three common monosaccharides?

Glucose: sugar found in blood

Galactose: part of lactose found in milk

Fructose: sugar found in honey or fruit

A disaccharide is..

Two monosaccharides joined together

Common disaccharides are..

Lactose

Sucrose

Maltose

Scenario 1: You just ate a big meal, and you need energy NOW!

(Describe the process carbs undergo)

1. Ate some carbohydrates

2. digestive enzymes break many

carbohydrates into monosaccharides

3. Cells can use glucose to produce

energy (ATP)

Scenario 2: You just ate a big meal, and you want to take a nap and save the energy for later!

(Describe the process carbs undergo)

1. Ate some carbohydrates

2. Digestive enzymes break many

carbohydrates into monosaccharides

3. Some glucose is used

4. Some glucose is stored as the

polysaccharide glycogen

• excess energy can also be stored

as fat

What is starch?

Amylose + amylopectin

• Amylose = linear chains

• amylopectin = branched chains

Plants make glucose through photosynthesis and then store it as starch

Animals consume plants, digest starch into glucose, which cells can use for energy

What is Glycogen?

• Storage form of glucose in animals and fungi

• Glucose is mainly stored in the liver and skeletal muscles for humans

• Glycogen is more highly branched

• Branching allows glucose to be released rapidly when energy is needed

What is Cellulose?

• Made up of glucose monomers

• Most abundant organic biopolymer on Earth

• Humans lack enzyme that digest its bonds (dietary fiber)

Examples of Cellulose are..

Plant cell walls

Wood

Paper

What is Chitin?

Chitin provides structural support

• Found in arthropod exoskeletons

• Insects

• Spiders

• Crabs

• Found in fungal cell walls

• Function: protection and support

Fats

long-term energy storage and insulation

Sterols

Regulate growth and development

Phospholipids

Form cellular membranes

True or False? Unsaturated fats are tightly packed fatty acids

False; They are crooked fatty acids and essentially and cannot be packed tightly because they are liquid at room temperature

True or False? Saturated fats are tightly packed fatty acids

True; This is because they are solid at room temperature

Steroids

Steroids have four fused carbon rings, a structure that distinguishes them from fats and phospholipids

Cholesterol

Part of animal cell membranes and helps maintain membrane fluidity

Phospholipids

Amphipathic

• Hydrophilic phosphate head –

interacts with water

• Hydrophobic fatty-acid tails –

avoids water

• Form the basic bilayer structure of

cell membranes

What are proteins?

Proteins are long chains of amino acids (a.a.) that are linked together by covalent bonds

What is the bond that holds the Amino Acids together?

Peptide bond

Amino acids that are linked together are called..

Polypeptides

Levels of a protein structure

1° (Primary)

• sequence of amino acids

• 2° (Secondary)

• repeating patterns

• 3° (Tertiary)

• three-dimensional folded structure

• 4° (Quaternary)

• Multiple polypeptides (Not every protein has 4° structure)

Denaturation

Disrupts a protein’s three-dimensional shape and often its function

Common causes:

• High temperature

• Extreme pH

• Certain chemicals

Ex: cooked egg

Examples of functions that proteins perform:

Hemoglobin transports oxygen in blood

Antibodies contribute to immune defense

Collagen supports connective tissues

What’s the monomer of Nucleic Acids?

Nucleotide

A nucleotide consists of:

Phosphate

• Sugar

• Nitrogenous base

The polymer of Nucleic Acids are..

Nucleic Acid

What is DNA?

Deoxyribonucleic acid (DNA)

• usually double stranded

• stores hereditary information

What is RNA?

Ribonucleic acid (RNA)

• usually single-stranded

• can fold into varied shapes

• helps express and regulate genetic information

DNA vs. RNA

DNA = C, G, A, U

RNA = C, G, A, T

What is this structure?

Carbohydrate

What is this structure?

Lipid structure

What is this structure?

Protein structure

What is this structure?

Nucleic Acid structure (Used to form DNA and RNA)