Energize me baby!
Energy can neither be created nor destroyed, but can change form
What is the first law of thermodynamics
___ are employed to catalyze (speed up) chemical reactions in cells by lowering the activation energy needed to start the reaction
What are Enzymes
The two strands in a DNA double helix are said to be ___; that is, they are oriented in opposite directions
What is antiparallel.
DNA information must be carried by an intermediary called _____, from the nucleus to the cytoplasm.
What is ribonucleic acid (RNA).
Translation begins when tRNA and mRNA bind to a _____.
What is a ribosome.
Each gene consists of two or more segments of DNA that encode for protein, called ___, that are interrupted by other segments that are not translated, called ___.
What are exons & introns.
The amount of useful energy decreases when energy is converted from one form to another
What is the second law of thermodynamics
All catalysts have three important properties
What is 1) They speed up reactions by lowering the activation energy required for the reaction to begin. 2) They speed up only exergonic reactions. 3) They are not consumed or changed by the reactions they promote.
Bases that bond with each other are called ___ base pairs. ___ bonds with __while __ bonds with __.
complementary; A/T & G/C
RNA differs structurally from DNA in three ways.
What is 1) RNA is usually single-stranded, 2) RNA has the sugar ribose rather than deoxyribose in its backbone, 3) RNA contains the nitrogenous base uracil (U) instead of thymine (T).
During elongation, ___ are added one at a time to the growing protein chain.
What are Amino acids.
The tendency to move toward a loss of complexity and of useful energy and toward an increase in randomness, disorder, and less-useful energy
What is Entropy
Each enzyme has a pocket called an ___ into which one or more reactant molecules, called ___, can enter.
What is an active site; substrates.
Genetic information is encoded in DNA. The key lies in the _____, not the ___, of subunits.
What is sequence, number.
The three types of RNA involved in protein synthesis.
What are
–Messenger RNA (mRNA) carries DNA gene information to the ribosome
–Transfer RNA (tRNA) brings amino acids to the ribosome
–Ribosomal RNA (rRNA) is part of the structure of ribosomes
Upon termination: a ___ codon signals the end of translation.
What is stop.
_____ reactions release energy
_____ reactions require an input of energy
What is Exergonic & Endergonic
In ___ pathways, an initial reactant molecule is modified by an enzyme, creating a slightly different intermediate molecule, which is modified by another enzyme, and so on, until a final product is produced
What are metabolic
The ingredients for DNA replication are threefold.
1) Parental DNA strands
2) Free nucleotides
3) A variety of enzymes that unwind the parental DNA double helix and synthesize new DNA strands
___, groups of three bases in mRNA, specify which amino acids will be incorporated into a protein.
What are codons.
Each DNA gene codes for a single ____.
What is a protein.
All chemical reactions require an initial energy input to get started. Molecules need to be moving with sufficient collision speed to overcome electronic repulsion and react.
What is activation energy
In ___ inhibition, a substance that is not the enzyme’s normal substrate binds to the active site of the enzyme, competing with the substrate for the active site
What is competitive.
_____: The two resulting DNA molecules have one old parental strand and one new strand
What is semiconservative replication.
A group of three bases, called a(n) ____, protrudes from each tRNA.
What is an anticodon.
A _____ mutation occurs when one or more nucleotides are removed from the gene sequence
What is a deletion.
___ is the most common energy-carrying molecule.
What is Adenosine triphosphate (ATP)
In ___ inhibition, a molecule binds to a site on the enzyme distinct from the active site
What is noncompetitive
Toxic chemicals, radiation, and occasional errors during DNA replication cause _____.
What are mutations.
The ____ translates the sequence of bases in nucleic acids into the sequence of amino acids in proteins.
What is the genetic code.
An ___ mutation occurs when one or more nucleotides are added to the gene sequence
What is an insertion
In a ___ reaction, an exergonic reaction provides the energy needed to drive an endergonic reaction
What is coupled
Enzyme structure is distorted (i.e. ___) and function is destroyed when pH and/or temperature is too high or low.
What is denatured.
This rule states there is a consistency in the equal amounts of adenine and thymine, and equal amounts of guanine and cytosine for a given species, although there was a difference in proportion of the bases.
What is Chargaff's Rule.
A ____ at the beginning of the gene marks where transcription is to be initiated.
What is a promoter region.
_____ and _____ occur when pieces of DNA are broken apart and reattached, within a single chromosome or to a different chromosome.
What are inversions and translocations.