Macromolecules Foldable Lecture Notes

Comprehensive vocabulary flashcards covering the four major classes of biological macromolecules (carbohydrates, lipids, proteins, and nucleic acids), their structural characteristics, functional roles, chemical bonds, and mechanisms.

Carbohydrates

Organic macromolecules composed of carbon, hydrogen, and oxygen in a $1:2:1$ ratio that serve as the main source of energy for cells.

Glucose

The most abundant monosaccharide and a major primary source of energy for cells.

Fructose

A monosaccharide carbohydrate found naturally in fruits.

Deoxyribose

A five-carbon pentose sugar found in DNA that lacks an oxygen atom at the $2'$ carbon.

Ribose

A five-carbon pentose sugar bearing a hydroxyl group ($-OH$) at the $2'$ position, found in RNA.

Sucrose

A disaccharide commonly known as table sugar, formed by joining glucose and fructose through a glycosidic bond.

Lactose

A disaccharide sugar found in milk composed of galactose bonded to glucose.

Cellulose

A structural polysaccharide composed of long monosaccharide chains that forms and strengthens plant cell walls.

Starch

A storage polysaccharide that represents the primary form in which glucose is stored in plants.

Glycogen

A branched polysaccharide representing the storage form of glucose in animals, stored in muscles for quick energy.

Dehydration Synthesis

A chemical reaction that joins two molecules or compounds together following the removal of a water molecule.

Hydrolysis

A chemical reaction that breaks apart two molecules or compounds by adding a water molecule.

Lipocytes

Cells specialized for storing excess fat in a fat reservoir, expanding in size until the stored fat is needed for fuel.

Fatty Acids

A major class of lipids found in an organism's body as fats and oils that function in energy storage, insulation (holding heat), and protection.

Saturated Fatty Acids

A hydrocarbon chain containing only single bonds between carbon atoms, typical of animal fats such as lard, butter, and meat fat.

Unsaturated Fatty Acids

A hydrocarbon chain containing one or more double bonds that can absorb additional hydrogen atoms, characteristic of plant fats like oils, nuts, and avocados.

Phospholipids

Lipid molecules composed of a hydrophilic head (glycerol and phosphate) and hydrophobic fatty acid tails that form the cell membrane and control transport.

Steroids

A class of working lipids found throughout the body that creates cholesterol, sex hormones, adrenaline, and cortisone to maintain body function.

Protein

Macromolecules composed of carbon, hydrogen, oxygen, nitrogen, and sulfur (CHONS) that account for roughly $15.1\%$ of body mass in healthy adults and function in growth, maintenance, catalysis, and structure.

Amino Acid

The monomer building block of proteins, consisting of a central alpha carbon ($C\alpha$), an amino group ($-NH_2$), a carboxylic acid group ($-COOH$), a hydrogen atom, and a variable R side chain.

Hemoglobin

A red blood cell protein composed of 2 $\alpha$ chains and 2 $\beta$ chains that transports oxygen via 4 binding sites.

Hemoglobin S

An abnormal variant of hemoglobin causing sickle cell disease, caused by a mutation changing glutamine in the 6th position of the $\beta$ chain to valine.

Primary Protein Structure

The linear sequence of a chain of amino acids in a polypeptide.

Secondary Protein Structure

The localized folding of the polypeptide chain into conformations such as $\alpha$-helices and $\beta$-pleated sheets.

Tertiary Protein Structure

The overall three-dimensional folding pattern of a protein stabilized by interactions between amino acid side chains.

Quaternary Protein Structure

A protein structure consisting of the association of more than one amino acid chain.

Four Levels of Protein Structure

The hierarchical organization of a protein: primary (chain sequence), secondary (local helices/sheets), tertiary (3D side chain folding), and quaternary (multiple chains).

Structural Proteins

Proteins that physically form your cells and body, providing basic structure, protection, and appearance.

Enzymes

Functional protein catalysts that accelerate biochemical reactions in the body by lowering the activation energy required.

Lock-and-Key Model

An enzyme model stating that the active site is precisely shaped to hold specific complementary substrates.

Induced-Fit Model

An enzyme model where the active site and substrate do not fit perfectly initially, but both alter their shapes upon binding to connect.

Activation Energy

The minimum energy threshold required to start a reaction, which is significantly lowered by enzyme catalysis.

Denature

The destruction of both the secondary and tertiary structures of a native protein due to extreme factors like heat or pH, leading to a total loss of biological function.

Competitive Inhibition

A process in which an inhibitor binds directly to the enzyme's active site, physically blocking substrate binding and preventing reaction.

Non-Competitive Inhibition

A process in which an inhibitor binds to an allosteric site on an enzyme, altering the active site's shape so the substrate cannot react.

Nucleic Acids

Polymers composed of carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHONP) that constitute the cell's genetic blueprint and carry instructions for protein synthesis.

Nucleotide

The fundamental monomer of nucleic acids, consisting of three components: a phosphate group, a pentose sugar, and a nitrogenous base.

Pyrimidines

Single-ring nitrogenous bases comprising cytosine (C), thymine (T in DNA), and uracil (U in RNA).

Purines

Double-ring nitrogenous bases consisting of adenine (A) and guanine (G).

DNA (Deoxyribonucleic Acid)

A double-helix nucleic acid containing deoxyribose sugar and bases A, T, C, and G that provides long-term information storage in all organisms.

RNA (Ribonucleic Acid)

A single-strand straight-chain nucleic acid containing ribose sugar and bases A, U, C, and G that transfers genetic code to the ribosome.

Protein Synthesis Pathway

The directional process through which genetic information produces functional proteins: DNA $\rightarrow$ RNA $\rightarrow$ Amino Acid $\rightarrow$ Protein.