chapter 2 ptC

Flashcards covering the vocabulary and concepts of carbohydrates, nucleic acids, and proteins from Chapter 02C: Atoms, Ions, and Molecules.

Monosaccharides

Simple sugar monomers typically defined by the general chemical formula $(CH_2O)_n$, where $n$ is the number of carbon atoms.

Disaccharides

Carbohydrates formed from the bonding of two monosaccharides.

Polysaccharides

Complex carbohydrates formed from many monosaccharide monomers.

Glucose

A six-carbon carbohydrate ($C_6H_{12}O_6$) that serves as the primary nutrient supplying energy to cells.

Glycogenesis

The process in which the liver and skeletal muscle bind excess glucose monomers together for storage.

Glycogenolysis

The process by which the liver hydrolyzes stored glycogen back into glucose as needed.

Gluconeogenesis

The formation of glucose by the liver from non-carbohydrate sources.

Glycogen

The most common polysaccharide in animals, used for storing glucose in the liver and skeletal muscle.

Hexose sugar isomers

Six-carbon monosaccharides with the same molecular formula as glucose but different structures, such as galactose and fructose.

Pentose sugars

Five-carbon monosaccharides, such as ribose and deoxyribose.

Common Disaccharides

Sucrose (table sugar), lactose (milk sugar), and maltose (malt sugar), all of which consist of glucose bonded to a second hexose monosaccharide.

Cellulose

A polysaccharide found in plants that serves as a source of nondigestible fiber for humans.

Glycosaminoglycans (GAGs)

Large carbohydrates with attached amine groups found in connective tissue; they form proteoglycans when attached to proteins.

Nucleic Acids

Polymers composed of nucleotide monomers that store and transfer genetic information, classified into DNA and RNA.

Nucleotide

A monomer consisting of a five-carbon pentose sugar, a phosphate group attached at carbon $5$, and a nitrogenous base attached at carbon $1$.

Phosphodiester bonds

Covalent links that join nucleotide monomers together in a nucleic acid strand.

Pyrimidines

Single-ring nitrogenous bases, which include Cytosine (C), Uracil (U), and Thymine (T).

Purines

Double-ring nitrogenous bases, which include Adenine (A) and Guanine (G).

Deoxyribonucleic acid (DNA)

A double-stranded nucleic acid located in chromosomes and mitochondria, containing deoxyribose sugar and the bases A, G, C, and T.

Ribonucleic acid (RNA)

A single-stranded nucleic acid located in the nucleus and cytosol, containing ribose sugar and the bases A, G, C, and U.

Adenosine triphosphate (ATP)

A nucleotide composed of adenine, ribose, and three phosphate groups that transfers chemical energy within a cell.

Amino acids

The monomers of proteins, each containing an amine group, a carboxyl group, a hydrogen, and a unique R (Remainder) group covalently linked to a central carbon.

Peptide bond

A covalent bond formed during dehydration synthesis between the amine group of one amino acid and the carboxylic acid group of another.

Oligopeptide

A strand of amino acids typically containing between $3$ and $20$ monomers.

Glycoproteins

Proteins with attached carbohydrates, such as those on erythrocytes that determine ABO blood groups.

Primary structure

The linear sequence of amino acids in a protein chain.

Conformation

The three-dimensional shape of a protein, which is crucial for its function and is maintained by intramolecular attractions.

Alpha helix

A spiral coil secondary structure that provides elasticity to fibrous proteins like skin and hair.

Beta sheet

A planar pleat secondary structure that provides flexibility to globular proteins such as enzymes.

Tertiary structure

The final three-dimensional shape of a single polypeptide chain, categorized as either globular or fibrous.

Quaternary structure

The level of organization present only in proteins consisting of two or more separate protein strands, such as hemoglobin.

Denaturation

A conformational change in a protein that disturbs its activity, often irreversible and caused by changes in temperature or pH.

Chaperones

Specialized proteins that assist in the folding of other proteins into their correct conformation.