Biomolecules: Carbohydrates, Lipids, Proteins, and Nucleic Acids

Vocabulary flashcards covering the structural characteristics, constituent elements, monomers, polymers, and key biological functions of Carbohydrates, Lipids, Proteins, and Nucleic Acids.

Carbohydrates

Biomolecules composed of carbon, hydrogen, and oxygen atoms in a $1:2:1$ ratio that serve as the primary immediate energy source for living organisms.

Monosaccharide

The single-ring monomer of carbohydrates, such as glucose or fructose.

Polysaccharide

A complex carbohydrate polymer made of hundreds of monosaccharide rings chemically bonded into long, branching chains, such as starch and cellulose.

Autotrophs

Organisms that build carbohydrates during photosynthesis.

Heterotrophs

Organisms that obtain carbohydrates by eating other organisms.

Lipids

A category of molecules including fats, oils, cholesterol, and steroids made of carbon, hydrogen, and oxygen, which serve in long-term energy storage and cell membrane formation.

Triglyceride

A lipid polymer formed when three fatty acid tails link up with a single glycerol head.

Cuticle

A waxy lipid substance produced by plant skin cells that covers their leaves to control water loss.

Proteins

Biomolecules composed of carbon, hydrogen, oxygen, and nitrogen ($\text{CHON}$) built from amino acid monomers, responsible for cellular growth, repair, enzymatic reactions, and hormone signaling.

Amino Acid

The monomer of proteins consisting of a central carbon atom surrounded by an amino group ($\text{NH}_2$), a hydrogen atom ($\text{H}$), a carboxyl group ($\text{COOH}$), and a unique $\text{R}$ side chain.

Peptide Bond

A type of covalent bond formed as the amino group and carboxyl group of adjacent amino acids link together.

Polypeptide

A polymer formed by combining amino acids in specific sequences, which becomes a protein when properly folded.

R-Group

The unique side chain on an amino acid; there are 20 different R-groups corresponding to the 20 different amino acids.

Enzymes

Essential globular proteins that act as biological catalysts to speed up chemical reactions needed to build or break down molecules.

Globular vs. Fibrous Proteins

The two primary structural classifications of proteins, where globular proteins are round and fibrous proteins are long.

Nucleic Acids

Biomolecules containing carbon, hydrogen, oxygen, nitrogen, and phosphorus ($\text{CHONP}$) that store and transmit genetic information and provide cellular energy.

Nucleotide

The monomer unit of nucleic acids, consisting of a phosphate group, a sugar molecule (ribose or deoxyribose), and a nitrogenous base.

DNA (Deoxyribonucleic Acid)

A double-stranded nucleic acid polymer containing deoxyribose sugar that holds inherited genetic information stored in chromosomes.

RNA (Ribonucleic Acid)

A single-stranded nucleic acid polymer containing ribose sugar that serves as a messenger between DNA instructions and protein-making machinery.

ATP (Adenosine Triphosphate)

A single, modified nucleotide without a polymer form that acts as the cell's energy currency, powered by energy released from glucose breakdown.

Carbohydrates

Biomolecules composed of carbon, hydrogen, and oxygen in a $1:2:1$ ratio, typically forming ring-like hexagon or pentagon structures that serve as the primary short-term energy source for living organisms.

Monosaccharide

The simplest single-ring monomer building block of carbohydrates, such as glucose and fructose.

Polysaccharide

A complex carbohydrate polymer made of hundreds of monosaccharide rings chemically bonded into long, branching chains, such as starch and cellulose.

Glucose

A monosaccharide carbohydrate built by autotrophs during photosynthesis and broken down by heterotroph cells to release immediate energy.

Cellulose

A polysaccharide carbohydrate that serves as a structural component in plant cell walls.

Lipids

Biomolecules composed of carbon, hydrogen, and oxygen that lack ring structures and are composed of a glycerol head and fatty acid tails, functioning in long-term energy storage, cell membranes, and insulation.

Glycerol

The head component of a lipid molecule that links up with fatty acid tails.

Fatty Acid

A tail-like building block of lipids, examples of which include stearic acid and linoleic acid.

Triglyceride

A lipid structure formed when three fatty acid tails link up with one glycerol head.

Cuticle

A waxy lipid substance produced by plant skin cells that covers leaves to control water loss.

Proteins

Biomolecules composed of carbon, hydrogen, oxygen, and nitrogen ($CHON$) built from amino acid monomers that perform essential cellular operations including growth, repair, and biological catalysis.

Globular Protein

A round-shaped protein structure, characteristic of functional proteins such as enzymes.

Fibrous Protein

A long, thread-like protein structure.

Amino Acid

The monomer building block of proteins, consisting of a central carbon atom bonded to an amino group ($NH_2$), a hydrogen atom ($H$), a carboxyl group ($COOH$), and a unique $R$ side chain.

R-group

The unique side chain on an amino acid that determines its chemical identity, existing in $20$ different variations across terrestrial life.

Peptide Bond

A specific type of covalent bond formed when amino groups and carboxyl groups of adjacent amino acids link together.

Polypeptide

A polymer chain of amino acids linked in specific sequences that folds to form a protein.

Enzymes

A major group of globular proteins that catalyze and speed up chemical reactions necessary to build or break down cellular molecules.

Hormones

Chemical messengers, such as insulin, that communicate between organs and organ systems to start or stop life processes.

Nucleic Acids

Biomolecules made of carbon, hydrogen, oxygen, nitrogen, and phosphorus ($CHONP$) that carry genetic information and serve as energy currency within organisms.

Nucleotide

The monomer unit of nucleic acids, consisting of a phosphate group, a pentose sugar molecule, and a nitrogenous base.

Deoxyribonucleic Acid (DNA)

A double-stranded nucleic acid polymer containing deoxyribose sugar and stored in chromosomes to hold inherited genetic instructions.

Ribonucleic Acid (RNA)

A single-stranded nucleic acid polymer containing ribose sugar that functions as a messenger between DNA instructions and protein-making cellular machinery.

Adenosine Triphosphate (ATP)

A single, modified nucleotide without a polymer form that acts as the cell's energy currency, with approximately $1\text{ billion}$ molecules present in every cell.