Chapter 1-7: Biology Lecture Review

Vocabulary flashcards covering key terms and concepts from lectures on biological macromolecules, cell structure, and metabolic processes.

Monosaccharide

A single sugar unit.

Polymer

A large molecule composed of many repeating smaller units (mers).

Polypeptide

A polymer made of many amino acids linked by peptide bonds.

Polysaccharide

A carbohydrate with many units of sugar.

Amphipathic

Having both hydrophilic ('water-loving') and hydrophobic ('water-fearing') properties or two sides.

Weight Loss (Mass Loss)

Approximately 80% of lost mass is exhaled as carbon dioxide through breath.

Krebs cycle

A metabolic process responsible for converting carbon from fat and sugar into carbon dioxide.

Dehydration reaction

A chemical reaction where two molecules are joined together by the removal of a water molecule.

Hydrolysis reaction

A chemical reaction where a molecule is broken apart by the addition of a water molecule.

Carbohydrates

Macromolecules that include sugars and polymers of sugars, used for storage and structure.

Glycosidic linkage

The covalent bond that joins monosaccharide units together to form disaccharides and polysaccharides.

Starch

A storage polysaccharide in plants, composed almost entirely of glucose monomers.

Glycogen

A storage polysaccharide in animals, found in the liver and muscles, that releases glucose when energy demand is high.

Cellulose

A structural polysaccharide that is a major component of plant cell walls, composed of glucose monomers with different glycosidic linkages than starch.

Insoluble fiber

Undigested cellulose that passes through the human digestive tract, promoting digestive health.

Chitin

A structural polysaccharide found in arthropod exoskeletons and used in surgical applications.

Lipids

Hydrophobic macromolecules that include fats, phospholipids, and steroids, important for biological functions.

Hydrophobic

Water-fearing; repelled by water due to nonpolar covalent bonds, typically between carbon and hydrogen.

Phospholipid

An amphipathic lipid that forms the lipid bilayer of cell membranes, with a hydrophilic polar head and hydrophobic nonpolar tails.

Steroids

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

Cholesterol

A steroid that is a crucial component in animal cell membranes, also associated with heart disease.

Proteins

Macromolecules that account for over 50% of the dry mass of cells and perform diverse functions including structural support, storage, transport, communication, movement, and defense.

Enzymes

Proteins that act as biological catalysts, speeding up chemical reactions (e.g., digestive enzymes like amylase).

Casein

The primary protein found in milk, serving as a major source of amino acids for infant mammals.

Oligomine (Albumin)

The protein found in egg whites, providing an amino acid source for the developing embryo.

Insulin

A hormonal protein secreted from the pancreas that helps normalize high blood sugar levels.

Antibodies

Proteins produced by the immune system that bind to specific viruses or bacteria, targeting them for immune action.

Keratin

A structural protein found in hair, fingernails, and feathers.

Amino acids

The monomers of proteins, each containing an amino group, a carboxyl group, an alpha carbon, and a unique side chain (R group).

Peptide bond

The covalent bond formed between the carboxyl group of one amino acid and the amino group of another, forming a polypeptide chain.

R group (Side chain)

The variable group attached to the alpha carbon of an amino acid, determining its specific chemical properties (nonpolar, polar, charged).

Nonpolar amino acids

Amino acids with hydrophobic R groups, typically composed mainly of carbons and hydrogens.

Polar amino acids

Amino acids with hydrophilic R groups containing electronegative atoms (like oxygen or nitrogen) that create partial charges, allowing interaction with water.

Charged amino acids

Amino acids with hydrophilic R groups that are either basic (positively charged) or acidic (negatively charged).

Structure dictates function

A fundamental principle in biology stating that the specific three-dimensional structure of a molecule (like a protein) determines its biological role and activity.

N terminus (Amino end)

The end of a polypeptide chain that has a free amino group.

C terminus (Carboxy end)

The end of a polypeptide chain that has a free carboxyl group.

Primary structure (Protein)

The unique, linear sequence of amino acids in a polypeptide chain, determined by genetic information.

Secondary structure (Protein)

Local, folded structures such as alpha helices and beta pleated sheets, stabilized by hydrogen bonds between atoms of the polypeptide backbone.

Alpha helix

A common secondary structure of proteins, characterized by a coiled spiral shape stabilized by hydrogen bonds.

Beta pleated sheet

A common secondary structure of proteins, characterized by a folded, zig-zag pattern stabilized by hydrogen bonds.

Tertiary structure (Protein)

The overall three-dimensional shape of a single polypeptide chain, resulting from interactions between the R groups (side chains) of amino acids.

Quaternary structure (Protein)

The overall protein structure formed by the aggregation of two or more polypeptide chains (subunits).

Collagen

A fibrous structural protein composed of three polypeptides wound together in a rope-like structure.

Hemoglobin

A globular protein in red blood cells that consists of four polypeptide subunits and is responsible for transporting oxygen.

Sickle cell disease (Sickle cell anemia)

A genetic disease caused by a single amino acid mutation (glutamic acid to valine) in the beta hemoglobin chain, leading to abnormal red blood cell shape and function.

Nucleic acids

Polymers (DNA and RNA) that serve to store, transmit, and express hereditary information.

DNA (Deoxyribonucleic acid)

A nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms.

RNA (Ribonucleic acid)

A nucleic acid involved in various roles in gene expression, including carrying genetic information from DNA to the synthesis of proteins.

Transcription

The process by which genetic information from DNA is copied into RNA.

Translation

The process by which information from RNA is used to synthesize proteins.

Eukaryotic cell

A type of cell characterized by the presence of a membrane-bound nucleus and other membrane-bound organelles.

Complementary base pairing

The specific hydrogen bonding patterns between nitrogenous bases in nucleic acids: adenine (A) with thymine (T) in DNA (or uracil (U) in RNA), and guanine (G) with cytosine (C).

Polynucleotide

A polymer made of many nucleotide monomers, forming a nucleic acid chain.

Nucleotide

The monomer unit of nucleic acids, consisting of a five-carbon sugar, a phosphate group, and a nitrogenous base.

Nucleoside

A nitrogenous base covalently bonded to a five-carbon sugar.

Deoxyribose

The five-carbon sugar found in DNA, distinguished by the absence of an oxygen atom at the 2' carbon position.

Ribose

The five-carbon sugar found in RNA, characterized by the presence of a hydroxyl (OH) group at the 2' carbon position.

Phosphodiester bond

A strong covalent bond that forms the sugar-phosphate backbone of DNA and RNA by linking the phosphate group of one nucleotide to the sugar of the next.

Antiparallel (DNA)

Describes the orientation of the two strands in a DNA double helix, where they run in opposite 5' to 3' directions.