Goal: Learn how the cell connects small biological molecules to make larger biological molecules
Synthesize: to form by combining parts.
Synthesis: bonding 2 molecules together to form a larger molecule.
Digestion: breaking larger molecules apart into pieces
monomer: a single unit
polymer: many units put together
polymerization: bonding many of the same molecule together, again and again, to make a large structure.
Cells bond small molecules – monomers – together to make a larger molecule – a polymer.
Here’s a simple way to think about it:
Polymerization can be more complex, like this:
Sugars & carbohydrates
The monomer here is a sugar
The polymer here is a carbohydrate
(There are many kind of carbs, including starch, fiber, etc.)
Rice, grains, cereals, and pasta, breads, tortillas, crackers, bagels and rolls
Dried beans, split peas and lentils
Vegetables, like potatoes, corn, peas and winter squash
Fruit, Milk, Yogurt, Sugars (like table sugar and honey)
Foods and drinks made with sugar, like regular soft drinks and desserts
Our small intestine has enzymes that can digest many carbohydrates into their component sugars, but not all. Plant carbs that our body can not break down are termed fiber.
Some fiber is in fruit, vegetables and whole grains. Fiber has near-zero calories.
Soluble fiber dissolves in water
Insoluble fiber doesn’t dissolve in water
Fiber is a polymer of sugars, just joined together in a way that we can’t digest.
Details of how two glucose bond to form maltose.
During digestion, your body has enzymes that digest carbs.
Water needs to be added in this process; since water is used to break the molecule, we call this process hydrolysis. (Latin: water-breaking)
How fats are used:
energy storage, building cell membranes, creating electrical insulation around our nerves so that they can transmit signals
The monomers discussed here will be glycerol, and fatty acids.
The polymer here could be triglycerides or phospholipids
Fatty acid: long chain of C and H atoms, with a cap of COOH atoms.
Glycerol: Used as a cap to tie together fatty acids.
It can also provide energy for cellular metabolism.
Glycerol + Fatty Acids = triglycerides
The monomer here is a phospholipid
The polymer here is the lipid bilayer (cell membrane)
A cell membrane is double-layer of fat molecules, which we find around every cell.
Here’s a simple drawing
Here’s a more detailed drawing
Let’s look at a single phospholipid molecule.
There are many forms. This is just one example
black = carbon
white = hydrogen
red = oxygen
blue = nitrogen
The main building blocks of deoxy ribo nucleic acid
The monomer here is a nucleotide
The polymer here is a gene
These are 4 different monomers.
The cell bonds nucleotides together into genes.
Here you can study DNA structure in more detail.
Then DNA nucleotides are synthesized into genes
The monomer here is an amino acid.
The polymer here is a peptide or protein.
These are 20 different types of common amino acids.
Amino acids are bonded together to make peptides, or proteins.
A peptide is just a small protein, less than 50 amino acids (aa) long.
Proteins are much larger, 100 aa, 500 aa, even 1,000 aa.
A chain of amino acids folds up into a shape.
Every protein has its own shape.
Proteins then fold into coils and sheets.
They become biological machines.
Their shape determines their function (“job”.)
8.MS-PS1-1. Develop a model to describe that (a) atoms combine in a multitude of ways to produce pure substances which make up all of the living and nonliving things that we encounter, (b) atoms form molecules and compounds that range in size from two to thousands of atoms, and (c) mixtures are composed of different proportions of pure substances.
Clarification Statement: Examples of molecular-level models could include drawings, three-dimensional ball and stick structures, and computer representations showing different molecules with different types of atoms.
HS-LS1-6. Construct an explanation based on evidence that organic molecules are primarily composed of six elements, where carbon, hydrogen, and oxygen atoms may combine with nitrogen, sulfur, and phosphorus to form monomers that can further combine to form large carbon-based macromolecules.
• Monomers include amino acids, mono- and disaccharides, nucleotides, and fatty acids.
• Organic macromolecules include proteins, carbohydrates (polysaccharides), nucleic acids, and lipids.