BIO 150 UNIT 1 LECTURE SET: Macromolecules: Structure and Function Overview, Principles of Life: Key Concepts in Biology

Macromolecules

Large molecules prevalent in all organisms.

Lipids

Insoluble in water, hydrophobic molecules.

Carbohydrates

Made from linked simple sugars.

Nucleic Acids

Informational macromolecules like DNA and RNA.

Proteins

Polymers with variable structures and functions.

Endergonic Reactions

Reactions that absorb energy to form bonds.

Condensation Reactions

Reactions that form covalent bonds by removing water.

Polymers

Large molecules formed from repeating monomers.

Monomers

Smaller molecules that make up polymers.

Hydrophobic

Repellent to water, nonpolar characteristics.

Triglycerides

Fats and oils made of three fatty acids.

Saturated Fatty Acids

Single bonds between carbon atoms, solid at room temperature.

Unsaturated Fatty Acids

One or more double bonds, liquid at room temperature.

Amphipathic

Molecules with both hydrophilic and hydrophobic parts.

Phospholipids

Molecules with hydrophilic heads and hydrophobic tails.

Phospholipid Bilayer

Structure formed by phospholipids in aqueous environments.

Lipoproteins

Spheres formed by proteins and phospholipids for lipid transport.

White Fat

Energy storage and thermal insulation fat.

Brown Fat

Fat with iron-rich mitochondria, important for thermoregulation.

Waxes

Lipids that repel water, coat plant leaves.

Carotenoids

Pigments that absorb specific wavelengths of light.

Steroids

Lipids including cholesterol and hormones.

Simple Sugars

Carbohydrates with 12 or fewer carbons.

Monosaccharides

Simple sugars with five or six carbons.

Disaccharides

Two monosaccharides linked by glycosidic bond.

Glycosidic Bond

Covalent bond linking monosaccharides.

Oligosaccharides

Three to ten monosaccharides joined together.

Polysaccharides

Polymers of hundreds to thousands of monosaccharides.

Cellulose

Structural polysaccharide in plant cell walls.

Chitin

Structural polysaccharide in fungal cell walls.

Starch

Energy storage polysaccharide in plants.

Glycogen

Energy storage polysaccharide in animals.

Pentoses

Five-carbon sugars in nucleic acids.

Nucleic Acids

Polymers storing and transmitting genetic information.

Nucleotides

Monomers of nucleic acids, containing sugar, base, phosphate.

Nucleoside

Pentose sugar and nitrogenous base.

Purines

Double-ring nitrogenous bases in nucleic acids.

Pyrimidines

Single-ring nitrogenous bases in nucleic acids.

Deoxyribose

Sugar in DNA nucleotides.

Ribose

Sugar in RNA nucleotides.

Uracil

Nitrogenous base replacing thymine in RNA.

Thymine

Nitrogenous base found only in DNA.

Amylase

Enzyme that hydrolyzes glycosidic linkages.

Recognition Signals

Oligosaccharides on cell membranes aiding cell communication.

Nucleotide

Building block of nucleic acids, containing sugar, phosphate, base.

Phosphodiester bond

Linkage between nucleotides in nucleic acids.

Sugar-phosphate backbone

Alternating sugar and phosphate chain in nucleic acids.

5' to 3' direction

Direction in which nucleic acids are synthesized.

Oligonucleotide

Short nucleic acid polymer, up to 20 monomers.

Polynucleotide

Long nucleic acid polymer, includes RNA and DNA.

RNA

Single-stranded nucleic acid, involved in protein synthesis.

DNA

Double-stranded nucleic acid, stores genetic information.

Complementary base pairing

Specific pairing of nucleotide bases (A-T, C-G, A-U).

Hydrogen bonds

Weak bonds forming between complementary bases.

Antiparallel strands

DNA strands running in opposite directions.

Double helix

Twisted structure formed by two DNA strands.

Base pairs

Pairs of nucleotides bonded via hydrogen bonds.

Gene expression

Transcription of DNA into RNA for protein synthesis.

Genome

Complete set of DNA in an organism.

DNA replication

Process of copying DNA into identical molecules.

Transcription

Synthesis of RNA from DNA template.

Translation

Synthesis of proteins from RNA sequence.

Amino acid

Building block of proteins, contains amino and carboxyl groups.

R group

Variable side chain in amino acids determining properties.

Structural diversity

Variety in protein structures due to amino acid differences.

Functional groups

Specific groups of atoms imparting distinct properties to molecules.

Polymers

Large molecules made of repeating subunits.

Oligopeptides

Short polymers of 20 or fewer amino acids.

Polypeptides

Larger polymers made of amino acids.

Peptide bonds

Links formed between amino acids in proteins.

Condensation reaction

Removes water to link amino acids.

Primary structure

Sequence of amino acids in a protein.

Secondary structure

Repeated patterns due to hydrogen bonding.

Alpha helix

Right-handed coil structure in proteins.

Beta pleated sheet

Extended and aligned sequences in proteins.

Tertiary structure

3-D shape from polypeptide chain folding.

Quaternary structure

Multiple polypeptide chains binding together.

Covalent disulfide bridges

Links between cysteine side chains.

Ionic bonds

Attractions between charged side chains.

Hydrogen bonds

Weak interactions between side chains.

Van der Waals interactions

Weak attractions between hydrophobic side chains.

Denaturing

Disruption of protein structure by heat or chemicals.

Ligand

Molecule or ion that binds to another molecule.

Structural proteins

Provide support and shape to cells.

Transport proteins

Carry substances across cell membranes.

Defensive proteins

Protect against pathogens and foreign substances.

Storage proteins

Store amino acids or other substances.

Conformational Change

Shape alteration affecting protein function.

Cofactors

Nonprotein molecules aiding protein function.

Proteolysis

Process of breaking peptide bonds in proteins.

Dynamic Proteins

Proteins undergo structural and chemical modifications.

Enzymes

Proteins that catalyze chemical reactions.

Activation Energy

Energy required to initiate a chemical reaction.

Specificity of Enzymes

Each enzyme catalyzes one specific reaction.

Active Site

Region on enzyme where substrates bind.

Induced Fit

Enzyme shape change upon substrate binding.

Enzyme-Substrate Complex

Temporary complex formed when enzyme binds substrate.

Metabolic Pathway

Series of reactions with interconnected products.

Catabolic Pathways

Break down molecules, releasing energy.

Anabolic Pathways

Synthesize complex molecules from simpler ones.