Module 3 - Macromolecules

Know the four major macromolecules

• Carbohydrates

• Lipids

• Proteins

• Nucleic Acids

Macromolecules:

• large organic molecule, usually comprising smaller molecules joined together to form a larger molecule.

Monomers:

• a smaller molecule that can be combined with other similar or identical molecules to create a polymer.

Polymers:

• a larger molecule made up of many similar or identical subunits.

Carbohydrates

• Monomers are simple sugars like glucose and fructose (monosaccharides).

• Polymers include starches, glycogen, and cellulose (polysaccharides).

Lipids

• These do not form true polymers.

• They are composed of distinct units like glycerol and fatty acids, which form larger structures such as triglycerides, phospholipids, and steroids.

Proteins

• Monomers are amino acids.

• They link together to form polymer chains called polypeptides, which then fold into functional proteins

Nucleic Acids

• Monomers are nucleotides, consisting of a sugar, a phosphate group, and a nitrogenous base.

• Polymers are polynucleotides, specifically DNA and RNA.

How does your body store unused energy (glucose) in the short term and in the long term? 

• Glucose provides molecular energy for the body.

• Excess glucose stored as glycogen in the short term or fat in the long term

Complex Carbohydrates 

• Energy production & structure.

• Simple carbohydrates (monomers).

• Glycogen: carbohydrate storage in animals.

• Starch: carbohydrate storage in plants.

• Complex Carbohydrates (Polymers):

Energy production & structure.

• 1:2:1 ratio

• Carbon:Hydrogen:Oxygen

Simple carbohydrates (monomers).

• Monosaccharides and Disaccharides

  • Glucose

  •  Fructose

  • Galactose

Glycogen: carbohydrate storage in animals.

• Stored in liver and muscle

Starch

• carbohydrate storage in plants.

Complex Carbohydrates (Polymers):

• Polysaccharides

  •  Starch

  •  Glycogen

  • Cellulose

  • Chiti

What are the functions of lipids? 

• non-polar molecules insoluble in water

  • Fats, oils, waxes, cholesterols and hormones

Lipid function: 

• Energy storage.

•  Cushion's internal organs.

•  Insulation.

•  Membrane Structure.

• Water storage.

• Toxic storage.

• Chemical Messengers.

Structure of a triglyceride

• lipid molecule formed by three fatty acids bonded to a glycerol.

  •  Most common lipid molecule found in foods

Differences between unsaturated and saturated fatty acids. 

• Saturated fatty acid: no double bonds.

  • Saturated with H atoms.

•  Unsaturated fatty acid: one or more

  • double bonds between carbon atoms.

What are hydrogenated fats? 

• Trans fats (lipids) 

Know common types of lipids (sterols, phospholipids and waxes). 

• (sterols,

• phospholipids

• and waxes). 

Sterols

• lipid with four interlocking carbon rings.

  • Cholesterol: important in animal cell membranes.

  • Testosterone and Estrogen: hormones important to the development of different sexes in humans

Phospholipids

• a charged lipid composed of a glycerol, a phosphate group, and two fatty acids

Waxes

• a single long chain fatty acid linked to a glycerol head.

  • Water repellant coating used by plants and animals.

Low-density lipoproteins (LDLs):

• cholesterol that travels from liver to body and can clog arteries of the heart.

  • “Bad cholesterol.”

  • Saturated fats and trans fats.

High-density Lipoproteins (HDLs):

• cholesterol that travels from body to liver, clearing cholesterol from the system.

  •  “Good cholesterol.”

  •  Omega-3 fatty acids.

Essential

• can't be produced by humans so you need to take them 

  • Two fatty acids are essential to humans:

    • Alpha-linolenic acid (omega-3 fatty acid).

    • Linoleic acid (omega-6 fatty acid)

Proteins

• a long, folded polypeptide.

  • Polypeptide = a chain of amino acids.

  • Amino acid = compounds consisting of an amino and carboxyl functional group, which act as the building block (monomers) of proteins.

    • 20 different amino acids

      • Nine essential to humans

Essential amino acids

• amino acids not produced by the body, which must be obtained through the diet.

  •  Nine in humans.

  •  All found in animal protein

What do enzymes do?

• Proteins that accelerate chemical reactions.

  • Catalysts: chemical agent that increases the rate of a reaction without being consumed by the reaction.

 What does it mean when an enzyme has become denatured? 

• Protein shape can be altered, disrupting function of protein.

How can enzymes become denatured? 

• Denaturing: loss of protein shape due to external stress or interaction with hazardous compounds. 

How is the function of an enzyme altered once they become denatured? 

Where do substrates bind to an enzyme?

• Active site 

What are enzymes made up of?

• Made up of a long chain of amino acids folded into complex, three-dimensional structures, which means they are classified as proteins

Protein Synthesis:

DNA is copied (transcription) and translated to make proteins

Nucleic Acids:

•  are large molecules made up of nucleotides.

 Nucleotides

• Organic molecules that serve as the building blocks (monomers) of nucleic acids, and are made up of a phosphate group, a sugar and a nitrogenous base.

DNA and RNA

• Instructions for making proteins.

ATP

• Energy transfer

 Deoxyribonucleic acid (DNA):

• primary information bearing molecule of life, composed of two linked chains of nucleotides (double helix).

Nitrogenous bases:

• Adenine

• Thymine

• Cytosine

• Guanine

• Uracil (RNA)

Ribonucleic acid (RNA):

•  active in protein synthesis and also forms part of ribosomes.

  • Uracil nucleotide instead of Thymine