SIMPLIFIED Organic Compounds

Lipids Elements

Carbon, Hydrogen, Oxygen (C, H, O — with very little oxygen)

Carbohydrates Elements

Carbon, Hydrogen, Oxygen (C, H, O in a 1:2:1 ratio)

Proteins Elements

Carbon, Hydrogen, Oxygen, Nitrogen (C, H, O, N — sometimes Sulfur)

Nucleic Acids Elements

Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus (C, H, O, N, P)

Lipid’s monomer

DON’T have a true monomers

The 2 main components of lipids:

1. ALWAYS composed of a glycerol backbone

2. fatty acid

(you don’t build complex lipids by connecting them so technically don’t have monomers)

protein’s monomers and its building blocks

amino acids

(they are the monomer but they still have their own key parts its made up of):

1. amino group (ALWAYS on LEFT)

2. carboxyl group (ALWAYS on RIGHT)

3. Central carbon

4. Hydrogen

5. R GROUP (the variable that changes between the 20 amino acids that affect the properties and shape of the acids, ultimately the proteins as well cuz that’s what the protein is made up of)

Carbohydrate monomer

monosaccharides (simple sugar/single sugar molecule)

ex. Glucose, Fructose, Galactose

Nucleic acid monomer + its main parts

Nucleotide

has 3 key parts:

1. Sugar: Ribose or Deoxyribose

2. Nitrogenous base

3. Phosphate group

Lipids vs Carbs (same elements, what makes them different)

Carbs - 1:2:1 C, H, O ratio

Lipids - PRIMARILY carbon and hydrogen (hydrocarbons) very little Oxygen

***bc it’s mostly hydrocarbon, it’s no polar, so it’s mostly hydrophobic (with exception of that both hydrophobic hydrophilic thing in phospholipids)

Lipids are also NOT in a ring shape (carbs are)

Triglycerides

Consists of a glycerol backbone and 3 fatty acid tails

Saturated vs Unsaturated

Saturated fats are SOLID at room temperature

• More likely to get STUCK in your bloodstream so it’s worse for you

Unsaturated fat is LIQUID at room temperature

• more flexible so LESS LIKELY to get stuck in your bloodstream so better for you

Unsaturated fat has a DOUBLE bond, saturated does NOT. (only difference)

Double bonds limit how many things you can attach so that means less hydrogens attached (removing these hydrogen bonds makes it more flexible)

Saturated —> COMPLETELY FULL of HYDROGEN

Phospholipids

Basically a triglyceride but instead of a 3rd fatty acid, it’s a PHOSPHATE group.

So it has:

1. glycerol

2. 2 fatty acids

3. PHOSPHATE GROUP

Bc of it’s makeup, it’s BOTH hydrophobic and hydrophilic (very unique).

• water INsoluble tail

• water soluble head (negative oxygen end)

This structure allows them to form the core lipid bilayers of cell membranes.

• Hydrophobic ("water-fearing") tails: The two fatty acid chains (long hydrocarbon chains). These nonpolar ends push away from water

• Hydrophilic ("water-loving") head: The phosphate group (often attached to a glycerol molecule and an additional polar or charged group like choline or serine). This polar end interacts with water.

Wax and natural steroids

Lipids

Very long carbon chains (structurally triglycerides that are MAD LONG)

Water proofer (non polar, hydrophobic)

Where do you find it?

1. feathers (bird can fly in rain cuz of the wax covering)

2. cuticle (so plants don’t lose water)

3. skin (oil on our skin —> protects from water cuz if it absorbs then the skin cracks)

Steroids

1. cholesterol

2. hormones

Why is protein’s polymers named with ‘peptide’?

1) understand how to connect amino acids:

dehydration synthesis (remove OH from the carboxyl group of the first amino acid and the H from the amino group from the very next amino acid. why do you call that gap in both amino acids —> PEPTIDE bond (the free-d up space connects the two acids!)

Hence: Dipeptide and polypeptide (the more you attach amino acids together)

Carbohydrate dimer

disaccharides

Ex. glucose + fructose = SUCROSE

ex. sucrose, lactose, maltose

2 monosaccharides combined

carbohydrate polymer

polysaccharide

Storage polysaccharide:

1. starch - (bread, pasta, potatoes, etc) how plants store excess glucose molecules. photosynthesis → glucose → excess → store as starch

2. glycogen - starch is to plants as glycogen is to animals. big meal → excess glucose → strung together into glycogen by our liver → stored

(you store fat when you BURN the energy you stored and ITS excess energy becomes fat)

Structural polysaccharide:

1. cellulose → important component of cell walls for plants, gives plants their strength (reason trees stand up)

Isomers

when molecules have the same molecular formula (# + types of atoms) but different structural arrangement (shapes). Unique shapes —> unique properties/behaviors

(Glucose and Fructose for example as well as Starch and cellulose)

Protein Uses and Examples

1. Enzymes

2. Antibodies

3. Hormones

4. Receptor

5. Membrane proteins

(role + function based on shape)

All 4 stages of making protein

1. Primary Structure

• What it is: The simple, linear sequence of amino acids linked together in a specific order, like letters spelling out a unique word.

• Key Bonds: Strong covalent peptide bonds formed between neighboring amino acids.

• Why it matters: Even changing a SINGLE amino acid in this sequence can alter the protein's final shape and prevent it from working (for example, sickle cell anemia is caused by a single amino acid swap in hemoglobin).

2. Secondary Structure

• Take the ordered amino acid chain and FOLD IT (pleated structure) or coil it (coiled structure)

• NON NEIGHBORING hydrogen bonding (NOT peptide bonds. Bc it’s hydrogen, it’s relatively weak) Key Bonds: Hydrogen bonds forming between the oxygen and hydrogen atoms of the peptide backbone.

3. Tertiary Structure

• Lit js crumbling up the pleated/coiled structure into a 3d glob structure thing

• where R GROUPS play a significant role

• The overall 3D shape of a single protein chain, formed as unique amino acid R-groups interact:

  • Hydrophobic (Water-Hating) R-groups: Non-polar R-groups try to escape the surrounding water. They bunch together and hide on the inside (core) of the folded protein.

  • Hydrophilic (Water-Loving) R-groups: Polar or charged R-groups are attracted to water, so they position themselves on the outside surface of the protein.

  • Charged R-groups (Ionic Bonds): Positively charged R-groups attract negatively charged R-groups, pulling distant parts of the chain together.

  • Sulfur R-groups (Disulfide Bridges): When two cysteine amino acids with sulfur-containing R-groups end up near each other, they form a strong covalent "staple" lock.

4. Quaternary Structure

• If everything goes according to plan, the protein will be formed and work as intended

• 2 or more polypeptide chains (1st 2nd and 3rd were just single polypeptide chains) connected to form a single protein molecule

• Basically, A complex formed when two or more folded protein chains (subunits) join together to function as one unit.

Carb uses

• Glucose: Used for immediate energy.

• Starch/Glycogen: Used for short-to-medium term energy storage.

• Cellulose: Provides structural support in plant cell walls.

Lipid uses

• Triglycerides: Long-term energy storage and insulation/cushioning.

• Phospholipids: Form the oily structural barrier of all cell membranes.

• Steroids: Act as chemical hormones/messengers. (cholesterol)

Nucleic Acids Uses

DNA: Stores permanent genetic instructions.

RNA: Copies instructions to help build proteins.

Notable lipid structure

largely non polar so hydrophobic (w exception of phospholipid)