Biological Molecules Review (Bio 157 Exam 1)

These flashcards cover key terms and concepts related to biological molecules, including carbohydrates, lipids, proteins, and nucleic acids, to assist in exam preparation.

Carbohydrates

Organic compounds made mainly of carbon, hydrogen, and oxygen, usually with a hydrogen:oxygen ratio of 2:1.

Lipids

Hydrophobic biological molecules composed mainly of carbon and hydrogen, with functions in energy storage and cellular structure.

Proteins

Large biomolecules made up of amino acids, perform a wide range of functions in organisms.

Nucleic Acid

Biological molecules essential to all forms of life, including DNA and RNA, which carry genetic information.

Monosaccharide

The simplest form of carbohydrates, consisting of a single sugar unit, e.g., glucose.

Disaccharide

A carbohydrate formed by the joining of two monosaccharides, e.g., maltose.

Polysaccharide

Complex carbohydrates made up of many monosaccharides linked together.

Glycosidic Bond

A bond formed between two sugar molecules through a dehydration reaction.

Hydrolysis

A chemical process that splits molecules by adding water.

Dehydration Reaction

A chemical reaction that involves the removal of water to bond molecules together.

Fructose

A simple sugar (monosaccharide) with the same formula as glucose but different structures, classified as an isomer.

Glucose

A simple sugar (monosaccharide) that is an important energy source in living organisms.

Cellulose

A polysaccharide that is a major component of plant cell walls, providing structural support.

Starch

A storage polysaccharide in plants composed of glucose units.

Glycogen

The storage form of glucose in animals, composed of glucose units.

Chitin

A structural polysaccharide found in the exoskeletons of arthropods and the cell walls of fungi.

Fatty Acids

Carboxylic acids with long hydrocarbon chains, which can be saturated or unsaturated.

Triglyceride

A type of lipid made from glycerol and three fatty acids, used primarily for energy storage.

Saturated Fatty Acids

Fatty acids that contain no double bonds between carbon atoms, leading to straight chains.

Unsaturated Fatty Acids

Fatty acids that contain one or more double bonds, resulting in kinks in the carbon chain.

Trans Fatty Acid

A type of unsaturated fatty acid that is artificially produced and can lead to health issues.

Phospholipid

A lipid that forms the cell membrane, consisting of two fatty acid tails and a phosphate group.

Atherosclerosis

A condition characterized by the buildup of plaques in arteries, often linked to high levels of saturated fat.

Peptide Bond

A covalent bond formed between amino acids in a protein, through a dehydration reaction.

Amino Acid

The building blocks of proteins, containing an amino group, carboxyl group, and a variable R group.

Dipeptide

A molecule formed by two amino acids linked by a peptide bond.

Polypeptide

A chain of amino acids linked together by peptide bonds.

Enzyme

Proteins that act as catalysts to speed up biochemical reactions.

Hydrophobic Interaction

The tendency of nonpolar substances to aggregate in aqueous solutions to minimize their exposure to water.

Ionic Bond

A chemical bond formed between oppositely charged ions.

Secondary Structure

The localized folding of polypeptide chains into structures such as alpha helices and beta sheets.

Tertiary Structure

The overall three-dimensional shape of a polypeptide, determined by interactions among various R groups.

Quaternary Structure

The structure formed when two or more polypeptide chains assemble into a single functional protein.

Domains

Distinct structural units within a protein that have specific functions.

Chaperone Proteins

Proteins that assist in the proper folding of other proteins.

Functional Groups

Specific groups of atoms within molecules that determine the characteristics and chemical reactivity of those molecules.

Isotope

Variants of a chemical element that have the same number of protons but different numbers of neutrons.

pH Buffer

A solution that resists changes in pH when acid or base is added.

Hydrophilic

Molecules that are attracted to water and can dissolve in it.

Hydrophobic

Molecules that repel water and do not dissolve in it.

Glycogenolysis

The process of breaking down glycogen into glucose.

Amylose

A form of starch consisting of long, unbranched chains of glucose.

Amylopectin

A branched form of starch composed of glucose units.

Covalent Bond

A chemical bond formed by the sharing of electron pairs between atoms.

Hydrogen Bond

A weak bond formed between two molecules based on electrostatic attraction.

Vander Waals Forces

Weak attractions between molecules due to transient local partial charges.

Cysteine

An amino acid containing a thiol group that can form disulfide bonds.

Proteins Functions

Functions include enzymes, transport, defense, support, motion, storage, regulation, and hormones.

Enzymatic Activity

The catalytic effect of enzymes in increasing the rate of chemical reactions.

Hemoglobin

A protein in red blood cells that carries oxygen.

Antibody

A protein produced by the immune system to identify and neutralize foreign objects.

Motif

A pattern of secondary structures found in proteins that often plays a role in function.

Nucleotide

The basic building block of nucleic acids, consisting of a sugar, phosphate group, and nitrogenous base.

DNA

Deoxyribonucleic acid, a double-stranded molecule that carries genetic information.

RNA

Ribonucleic acid, a single-stranded molecule involved in protein synthesis.

Gene

A sequence of nucleotides in DNA that encodes for a functional product.

Codon

A sequence of three nucleotides in mRNA that specifies a particular amino acid.

R Group

The variable group of atoms in an amino acid that distinguishes it from others.

Carboxyl Group

A functional group (-COOH) found in amino acids, responsible for their acidic properties.

Amino Group

A functional group (-NH2) that acts as a base and accepts protons.

Hydrocarbon Chain

A chain consisting of carbon and hydrogen atoms, typical in fatty acids.

Steroids

Lipids characterized by a carbon skeleton consisting of four fused rings.

Anabolic Steroids

Synthetic forms of testosterone that promote muscle growth.

Prostaglandins

Modified fatty acids that function as local signaling molecules.

Transcription

The process of copying a segment of DNA into RNA.

Translation

The process of synthesizing proteins based on the sequence of mRNA.

Biological Molecules

Organic compounds that are essential to life, including carbohydrates, lipids, proteins, and nucleic acids.

Keto Group

A functional group featuring a carbon atom double-bonded to an oxygen atom.

Organic Molecule

Molecules primarily made of carbon atoms, often in combination with hydrogen, oxygen, nitrogen, and other elements.

Structural Formula

A graphic representation showing the arrangement of atoms within a molecule.

Alpha Configuration

A specific orientation of a hydroxyl group in sugar molecules, indicating the position of the OH group on carbon 1.

Beta Configuration

An orientation of the hydroxyl group in sugar molecules that indicates the OH group on carbon 1 is positioned at the top.

Carbohydrate Function

Primarily used for energy storage and providing structure in cells.

Lipid Function

Includes energy storage, insulation, forming cell membranes, and signaling.