Chapter 2 - Bonds Flashcards
How many naturally occurring elements are there?
92
What is the most abundant substance in the cell?
Water
What are the pyrimidines?
Thymine
Uracil
Cystine
What are the purines?
Adenine
Guanine
Which type of bond has pair of electrons that are shared between pairs of atoms?
Covalent bonds
What is the major component of plant cell walls?
cellulose
What term is used to describe the expanding field of protein biochemistry?
Proteomics
Chemically what can cause water to be excluded from a region what is this called?
-lack of free tumble of water molecules (entropy)
-lack of hydrogen bond forming opportunities (enthalpy)
Hydrophobic effect
When two specie associate due to charge neutralization what is this called?
Electrostatic interaction
Two carbon atoms are very close together, and as such the nucleus of one atom is attracted to the electron cloud of the neighboring atom?
Van Der Waal
What are the main elements of life? (5)
- hydrogen
- carbon
- oxygen
- nitrogen
- sulfur
What is a polar bond?
A covalent bond where the electrons are shared unequally
Why are weak bonds so important? (4)
- they can be formed/broken without huge changes in energy
- they are strong in large numbers
- they allow for small/temporary changes in structure
- they provide a degree of stability in structure
What is the monomeric form of a protein?
Amino Acid
What is the storage form of glucose in animal cells?
Glycogen
What are the functions of sugars? (5)
- production/storage of energy
- cell walls
- Extracellular matrix
- DNA/RNA
- linked to proteins
How are fatty acid monomers held together?
Hydrophobic effect
What does amphipathic mean? Give an example of a molecule.
-a molecule that can associate w/hydrophilic and hydrophobic materials
I.E. Phospholipids
What drives the formation of the secondary structure of a peptide chain?
Hydrogen bond formation between backbone atoms
What is the single letter code for tryptophan?
W
In a water molecule the bond between hydrogen and oxygen is best described as a?
Polar Covalent Bond
When sodium and chlorine interact, the single electron in the outer shell of each sodium atom migrates to the electronegative chlorine atom. As a result these two atoms are transformed into charged _______.
Ions
_________ are extremely reactive and capable of chemically altering many types of molecules, including proteins, Nucleic acids, and lipids.
Radicals
What are considered a prion disease?
- BSE
- Kuru
- Creutzfeldt-Jakob Disease
What are the reasons protein folding is a controversial topic?
- debates as to whether or not all of them are members of a population of unfolded proteins of a single species fold along a similar pathway or fold by means of a diverse set of routes that somehow converge upon some naive state.
- debates among the types of events that occur at various stage during the following process
- different interpretation of results that are required to study complex molecular events that occur on the microsecond timescale
Which level of protein organization describes the conformation of portions of the polypeptide chain?
Secondary
How many acids are incorporated into a protein encoded in the sequence of nucleotides in DNA?
20
Some proteins fold into their final confirmation by themselves; others require assistance of nonspecific _________, which prevent aggregation of partial folded intermediates.
Chaperones
A gram of fat contains ______ the energy content of a gram or carbohydrate.
6 times
Water is an excellent solvent capable of forming hydrogen bonds w/virtually all_______ molecules.
Polar
Ionic
What is an ionic bond?
A transfer of electrons (NaCl)
What is a covalent bond?
Sharing of electrons (H2O)
What are hydrogen bonds?
2 electronegative atoms attempting to share a positively charged ion between them
What are electrostatic bonds?
Regions of positive charge interactions with a negative charge
What is a Van Der Waals interaction?
Unshielded nucleus of an atom is attracted to the electron cloud of a nearby atom
What are the properties of water? (3)
- highly asymmetric
- highly polarized covalent bonds
- oxygen is adept at forming hydrogen bonds
What are the fates of the 4 major families of organic molecules?
Sugars become polysaccharides
Fatty Acids become fats/lipids/membranes
Amino acids become proteins
Nucleotides become Nucleic acids
What are the function of fats? (5)
- production and storage of energy
- cell membranes
- cell signaling
- steroids
- signal transduction
What are the function of amino acids?
- generation of proteins
- energy source
What is a peptide bond?
The bond that joins amino acids to a polypeptide chain. They result from the linkage of the carboxylic group of one amino acid group to the amino group of its neighbor w/the elimination of a molecule of water.
What is a primary protein?
-protein described by the amino acid sequence of a polypeptide
What is a secondary protein?
The 3D structures of the sections of the polypeptide backbone (alpha helix, beta sheet, random coil)
What is a tertiary protein?
The conformation of the entire polypeptide (helices, sheets and coils that fold together)
What is a quaternary protein?
Arrangement of subunits
Why is the primary structure of protein tertiary?
- it is the most accessible structure w/lowest energy
- most thermodynamically stable
What are the functions of nucleotides? (5)
- DNA (A,G,C,T)
- RNA (A,G,C,U)
- carries chemical energy (ATP)
- signaling molecules
- coenzymes
The properties of cells and their organelles derive directly from the activities of the _______ of which they are composed.
Molecules
