Organic Compounds

Dehydration Synthesis/Condensation VS Hydrolysis

Dehydration Synthesis/Condensation: take smaller pieces and build them up into something larger and more complex by FORMING WATER then REMOVING IT

• "Dehydration" = losing water (you pull water out to stick things together).

• "Synthesis" = putting together.

Hydrolysis: exact OPPOSITE. break down larger and more complex structures into individual pieces by USING water

Biomolecules (like proteins, carbohydrates, and nucleic acids) are made of individual building blocks called monomers. To link them together or break them apart, cells manipulate the atoms that make up a water molecule H20: a Hydrogen atom (-H) and a Hydroxyl group (-OH).

Dehydration Synthesis:

1. One smaller molecule contributes a Hydroxyl group (-OH).

2. The other smaller molecule contributes a Hydrogen atom (-H).

3. The -OH and -H combine to form a water molecule (H20).

4. Removing that water leaves open chemical bonds on both monomers, which snap together to form a covalent bond.

So water is REMOVED

Hydrolysis:

1. A water molecule H20 is added and split apart into -OH and -H

2. The covalent bond holding the large molecule together is broken.

3. The -OH attaches to one piece.

4. The -H attaches to the other piece.

So water is ADDED

Fats vs Oils (Lipids)

Fats are SOLID at room temperature

Oils are LIQUID at room temperature

Elements that make up lipids:

1. Carbon

2. Hydrogen

3. Oxygen

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)

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)

Triglycerides

Consists of a glycerol backbone and 3 fatty acid tails

Saturated vs Unsaturated

1. Saturated fats are SOLID at room temperature

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

1. 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.

Which store energy?

BOTH carbs and lipids but they are a little bit different:

Carbs - don’t store energy itself but stores GLUCOSE

Lipids - stores ACTUAL energy

Lipids technically store MORE energy (equal amount of carbs and lipids —> lipids store more energy)

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

Elements of protein

1. carbon

2. hydrogen

3. oxygen

4. nitrogen

5. a little bit of sulfur

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)

20 amino acids?

we can make 12 amino acids on our OWN, but 8 we have to EAT to get (called essential amino acids)

What differs all 20 amino acids?

the R GROUP!

the R GROUP isn’t an element or compound or anything… it’s a variable that’s filled in differently between all the acids!

this will determine the chemical property (nonpolar vs polar, positive/negative/neutral, acid/base, etc) of the amino acid, and therefore ultimately determine the shape and property of the protein

2 amino acids combined, 3 combined?

2 combined: Dipeptide

3 combined: Polypeptide

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)

Elements in Carbohydrates

1. Carbon

2. Hydrogen

3. Oxygen

1:2:1 ratio ALWAYS

(CH₂O)_n

2 monomers combined called

dimer

Carbohydrate monomer

monosaccharides (simple sugar/single sugar molecule)

ex. Glucose, Fructose, Galactose

Carbohydrate dimer

disaccharides

Ex. glucose + fructose = SUCROSE

ex. sucrose, lactose, maltose

they are disaccharides made up of two monosaccharide monomers joined together

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)

why eat starch and not sugar before a big race?

you break simple sugars QUICKER —> excess energy —> store as fat.

Starch molecules are BIG so you gotta break em down first and THEN you get energy so it’s longer energy supply

shape of glucose and fructose

circular/ring-shaped (shape of most carbs… specifically monosaccharide)

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)

Starch and cellulose are…

ISOMERS of each other

you CAN digest starch

you CAN’T digest cellulose

Protein Uses and Examples

1. Enzymes

2. Antibodies

3. Hormones

4. Receptor

5. Membrane proteins

(role + function based on shape)

Structure of protein

1. 3d shape

2. globular shape

that like curve inside the shape is called the binding/active site

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.

Nucleic Acid Elements

1. Carbon

2. Hydrogen

3. Oxygen

4. Nitrogen

5. Phosphorus (new one!)

Nucleic acid monomer + its main parts

Nucleotide

has 3 key parts:

1. Sugar: Ribose or Deoxyribose

2. Nitrogenous base

3. Phosphate group

2 main types of nucleic acid

DNA and RNA (NA - nucleic acid)

Basically polymers made up of nucleotides put tg in a chain

DNA

2 strands of multiple linked nucleotides.

Stores + links ur genetic info (brown vs black hair, green vs blue eyes, love vs hate cilantro)

Notable lipid structure

largely non polar so hydrophobic (w exception of phospholipid)

Why is carbon able to form so many different types of compounds

Because carbon has four valence electrons, allowing it to form single, double, and triple bonds, as well as straight, branched, and ring chains.

What is the process called when water is removed to join two molecules together?

Dehydration synthesis/Condensation

Which of the following best describes a polymer?

A large molecule made up of repeating units (monomers)

How does hydrolysis affect large carbon molecules?

It breaks them down by adding water

Explain the difference between dehydration synthesis and hydrolysis in the context of large carbon molecules.

Explain the difference between dehydration synthesis and hydrolysis in the context of large carbon molecules.

What is the general chemical formula for carbohydrates?

(CH₂O)_n

What term is used to describe molecules that have the same chemical formula but different structures?

Isomers

Explain the difference between monosaccharides and disaccharides in terms of their structure and give an example of each.

Monosaccharides have one sugar unit, disaccharides have two; examples: glucose (monosaccharide), sucrose (disaccharide)

Which two monosaccharides combine to form sucrose?

Glucose and fructose

Explain the process by which glucose and fructose combine to form sucrose. What type of reaction is this, and what is released during the process?

It is a dehydration synthesis reaction, and water is released.

Explain how polysaccharides contribute to both energy storage and structure in living organisms. Use examples from the material.

Starch and glycogen store energy, while cellulose provides structure.

What is the basic subunit that makes up the structure of starch?

Glucose

Why is it important for starch to be made up of glucose subunits?

Because glucose is easily broken down for energy

What is the backbone structure of a lipid molecule?

Glycerol

What is the main difference between saturated and unsaturated fatty acids?

Saturated fatty acids have only single bonds, while unsaturated fatty acids have one or more double bonds.

Which of the following is a component of phospholipids but not triglycerides?

Phosphate group

Phospholipids have both hydrophobic and hydrophilic properties. How does this structure benefit their function in biological membranes?

It allows them to form bilayers that create a barrier between the inside and outside of cells.

• Phospholipid Structure: An amphipathic molecule with a hydrophilic (water-loving) phosphate head and two hydrophobic (water-fearing) fatty acid tails.

• Function in Membranes: Spontaneously forms a bilayer (heads facing water outside, tails hidden inside) that creates a selective barrier to keep cell contents in and control what enters or leaves.

1. Why it creates a barrier: Because the entire middle layer of this sandwich is made of oily, water-fearing tails, anything dissolved in water (like salts, sugars, or big molecules) cannot pass through the oily middle.

It acts like an oil slick around the cell. Water-based stuff inside the cell stays trapped inside, and water-based stuff outside stays out. The cell gets total control over its border!

What is the main structural difference between an unsaturated fatty acid group and a polyunsaturated fatty acid group?

Unsaturated fatty acids have one double bond, while polyunsaturated have multiple double bonds

Suppose you are given a fatty acid chain with two double bonds. According to the diagram, how would you classify this fatty acid group?

Polyunsaturated fatty acid group

What is the main difference between a fat molecule and a phospholipid molecule as shown in the diagram?

Phospholipids have a phosphate group, fats do not

Why is the "tail" of a phospholipid molecule described as water-insoluble?

Because it is made of fatty acids

Which of the following is a characteristic of waxes?

They contain very long carbon chains.

Explain why the R group in amino acids is important for protein diversity.

The R group determines the specific properties and functions of each amino acid, leading to protein diversity.

Explain why proteins are considered essential for various functions in living organisms, using at least two examples from the list provided.

Proteins act as enzymes to speed up chemical reactions and as antibodies to help defend against diseases.

Carb property

Water-soluble (hydrophilic)

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.

Nucleic Acids Uses

• DNA: Stores permanent genetic instructions.

• RNA: Copies instructions to help build proteins.

Nucleic Acids Polymer

Polynucleotide

Proteins polymer

Polypeptide (protein chain)

Lipids Polymer

N/A (Lipids do not form true polymers; they are built from glycerol and fatty acids)