Chapter 5 Vocabulary Flashcards
Purines
Purines are larger than pyrimidines, with a six-membered ring fused to a five-membered ring. Adenine and Guanine are purines.
Pyrimidines
A pyrimidine has a six-membered ring of carbon and nitrogen atoms. They include cytosine, thymine, and uracil.
Double Helix
Cellular DNA molecules have two polynucleotides that spiral around an imaginary axis, forming a double helix.
Polynucleotides
Nucleic acids are macro molecules that exist as POLYMERS called polynucleotides. Each polynucleotide consists of monomers called nucleotides.
Nucleotide
A nucleotide is composed of three parts, a nitrogenous base, and pentose, and a phosphate group.
Pentose
Pentose is a five-carbon sugar
Chaperone Proteins(Chaperonins)
Protein molecules that assist the proper folding of other proteins. Chaperonins do not specify the correct final structure of the protein, but rather keep the new polypeptide segregated from “bad influences” and it folds spontaneously.
Denaturation
If pH, salt concentration, temperature, or other aspects of the environment are altered, the protein may unravel and lose its native conformation. Because it is misshapen, the denatured protein is biologically inactive.
Di-sulfide Bridges(Covalent)
Di-sulfide bridges form where two cysteine monomers, amino acids with sulfhydyl groups on their side chains, are brought close together by the folding of the protein.
Glycosidic linkage
A covalent bond formed between two monosaccharides by a dehydration reaction.
Monomers
The repeating units that serve as building blocks
Polymers
A polymer is a large molecule that consists of many similar or identical building blocks linked by covalent bonds, such as a train consists of many cars linked together.
Condensation Reaction & Dehydration Reaction
Monomers are connected to one another by a reaction through the loss of a water molecule. Since this reaction makes bonds between two monomers, it is a condensation reaction. However, since a water molecule is taken out, it is also a dehydration reaction.
Enzymes
Enzymes are specialized proteins that speed up chemical reactions in cells.
Hydrolysis
Hydrolysis is the addition of water in order to break a covalent bond between two monomers. A hydroxyl group(-OH) bonds to one monomer, and a Hydrogen(-H) bonds to the other.
The Digestive Process
Digestion hydrolyzes through the use of enzymes in order to speed up the digestive process. The monomers are then absorbed into the bloodstream and distributed to all the cells. Later on, the monomers can be reassembled or made into other polymers. The new polymers perform specific functions required by the cell.
Carbohydrates
Carbohydrates include both sugars and the polymers and monomers of sugars.
Monosaccharides
The simplest sugars, usually take some form of CH2O. They are made of a carbonyl group(>C=O) and multiple hydroxyl groups. Glucose and fructose are both monosaccharides.
Disaccharides
A disaccharide is two monosaccharides joined by a glycosidic linkage. Maltose and sucrose are both disaccharides, along with lactose.
Polysaccharides
Polysaccharides are macro molecules with a few hundred to a few thousand monosaccarides. They come in two groups: Structural or Storage.
Structural Poly S.
Cellulose is a structural polysaccharide.
Storage Poly S.
Starch is a storage polysaccharide.
Chitin
Chitin is a structural polysaccharide. It is used by arthropods(spiders, insects, crustaceans) to make the exoskeleton.
Fat/Glycerol/Fatty Acid
A fat is constructed from two kinds of smaller molecules: glycerol and fatty acids. A glycerol is an alcohol with three carbons, each bearing a hydroxyl group. A fatty acids has a long carbon skeleton, usually 16-18 carbon atoms in length. At the end of the fatty acid is a carboxyl group, the functional group that gives these molecules the name “fatty acid.”
Ester Linkage
An ester linkage is a bond between a hydroxyl and carboxyl group.
Gene
The amino acid sequence of a polypeptide is programmed by a unit of inheritance, known as a gene.
Primary Structure
The primary structure of a protein is its unique sequence of amino acids.
Tertiary Structure
The tertiary structure is the overall shape of a polypeptide resulting from interactions between the side chains(R groups). One type of interaction that contributes to the tertiary structure is hydrophobic interaction.
Quaternary Structure
Some proteins consist of two or more polypeptide chains aggregated into one functional macro-molecule. Quaternary structure is the overall protein structure that results from the aggregation of these polypeptide sub-units.
Conformation(of Proteins)
Conformation is the pattern in which a protein folds. A proteins specific conformation determines how it works. The amino acid sequence determines what three-dimensional conformation the protein will take.
Amino Acid
An amino acid is an organic molecule that possesses both carboxyl and amino groups. It is a monomer of proteins/polypeptides.
Proteins
- Structural: Support
- Storage: Stores amino acids
- Enzymes: Acceleration of chemical reactions
- Receptor: Response of cell to chemical stimuli
- Defensive: Protection against disease
- Motor/Contractile: Movement
- Hormonal: Coordination of organism’s activities
- Transport: Transport of other substances
Hydrophobic Interaction
In hydrophobic interaction, amino acids with a hydrophobic side usually end up in clusters at the center of the protein- out of contact with water.
Steroid
Steroids are lipids characterized by a carbon skeleton consisting of four fused rings. Cholesterol and sex hormones are both steroids.
Triacylglycerol = Triglyceride
A triglyceride consists of three fatty acids linked to a glycerol molecule.
Deoxyribo/ribo- Nucleic Acid
These are the molecules that enable living organisms to reproduce their complex components from one generation to the next. DNA provides directions for its own replication and for RNA synthesis. RNA controls protein synthesis.
Nucleic Acids
Nucleic acids are polymers of nucleotides. A nucleotide consists of three parts: a nitrogenous base, a pentose(5 carbon sugar, and a phosphate group.
Chaperonins
Protein molecules that assist the proper folding of other proteins.
Cholesterol
Cholesterol is a common component of animal cell membranes and the precursor from which other steroids are synthesized.
