-
promoter
a site where the transcription enzyme, RNA polymerase, attaches and initates transcription, determines which of the two strands of the DNA double helix is used as the template in trascription
-
operator
DNA control sequence, acts as a switch, determines whether RNA polymerase can attach to the promoter and start transcribing the gene
-
operon
cluster of genes with related functions, exist ONLY in prokaryotes
-
repressor
protein that turns off transcription, functions by binding to the operator and physically blocking the attachment of RNA polymerase to the promoter
-
regulatory gene
ocated outside the operon, codes for the repressor
-
activators
activatorsproteins that turn operons on by binding to DNA, make it easier for RNA polymerase to bind to the promoter
-
histones
crucial aspect of DNA packing, account for about half the mass of eukaryotic chromosomes --> small proteins grouped and wrapped around a DNA strand to form a nucleosome
-
nucleosome
consists of DNA wound around a protein core of 8 histone molecules
-
transcription factors
eukaryotic RNA polymerase requires the assistance of these proteins, such as activator proteins
-
enhancer
DNA control sequences, part of the first step in initiating gene transcription --> binding of activator proteins to these
-
microRNA (miRNA)
small RNA molecules that can bind to complementary sequences on mRNA molecules
-
RNA interference (RNAi)
procedure that involves injecting miRNa into a cell that can turn off expression of a gene with a sequence that matches the miRNA
-
oncogene
can cause cancer when present in a single copy in the cell
-
proto-oncogene
normal gene that has the potential to become an oncogene
-
tumor suppressor genes
proteins they encode help prevent uncontrolled cell growth/tumors
-
restriction fragment length polymorphism (RFLP)
variation in the lenght of a restriction fragment, produced when homologous DNA sequences containing SNPs are cut up with restriction fragments
-
transcription
the synthesis of RNA under the direction of DNA
-
translation
the synthesis of protein under the direction of RNA
-
codons
the genetic instructions for the amino acid sequence of a polypeptide chain are written in DNA and RNA as a series of nonoverlapping three-base "words"
-
RNA polymerase
transcription enzyme, links together the growing chain of RNA nucleotides during transcription, using a DNA strand as a template
-
terminator
that signals the end of the gene
-
mRNA messenger RNA
the type of ribonucleic acid that encodes the genetic information from DNA and conveys it to ribosomes, where the information is translated into amino acid sequences
-
introns
internal non-coding regions
-
exons
coding regions, the parts of a gene that are expressed
-
RNA splicing
the removal of introns and joining of exons in eukaryotic RNA, forming an mRNA molecule with a continuous coding sequence, occurs before mRNA leaves the nucleus
-
transfer RNA (tRNA)
a type of ribonucleic acid that functions as an interpreter in translation --> each molecule has an anticodon, picks up a specific amino acid, and conveys the amino acid to the appropriate codon on mRNA
-
ribosomes
structures in the cytoplasm that position mRNA and tRNA close together and catalyze the synthesis of polypeptides
-
ribosomal RNA (rRNA
a type of ribonucleic acid consisting of nucleotide monomers with a ribose suger and the nitrogenous bases A, C, G, U; usually single-stranded, fuctions in protein synthesis, gene regulation
-
start codon
specific codon that an mRNA molecule binds to where translation is to begin on the mRNA molecule
-
stop codon
in mRNA, one of the tree triplets (UAG, UAA, UGA) that signal gene translation to stop
-
silent mutation
a mutation in a gene that changes a codon to one that encodes for the same amino acid as the original codon --> the amino acid sequence of the resulting polypeptide is thus unchanged
-
missense mutation
a change in the nucleotide sequence of a gene that alters the amino acid seqeunce of the resulting polypeptide --> a codon is changed from encoding one amino acid to encoding a different amino acid
-
nonsense mutation
a change in the nucleotide sequence of a gene that converts an amino-acid-encoding codon to a stop codon --> results in a shortened polypeptide
-
Transcription
RNA Splicing
Translation
Post-Translational Modification
Steps in Gene Expression include what?
-
induction
Enzyme induction is a process in which a molecule induces the expression of an enzyme
-
Repression
Repression, in metabolism, a control mechanism in which a protein molecule, called a repressor, prevents the synthesis of an enzyme by binding to—and thereby impeding the action of—the deoxyribonucleic acid that controls the process by which the enzyme is synthesized
-
allosteric
allosteric regulation (or allosteric control) is the regulation of an enzyme by binding an effector molecule at a site other than the enzyme's active sit
-
cAMP or Cyclic adenosine monophosphate
2nd messenger of biological processes,
-
TATA box
DNA sequence that indicates where a genetic sequence can be read and decoded. It is a type of promoter sequence, which specifies to other molecules where transcription begins
-
coactivator
protein that increases gene expression by binding to an activator (transcription factor) which contains a DNA binding domain.
-
Acetylation
is the process where an acetyl functional group is transferred from one molecule (in this case, Acetyl-Coenzyme A) to anothe
-
-
alternative splicing
Alternative splicing, or differential splicing, is a regulated process during gene expression that results in a single gene coding for multiple proteins.
-
Ubiquitin
a compound found in living cells that plays a role in the degradation of defective and superfluous proteins. It is a single-chain polypeptide.
-
Proteasome
The main function of the this is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks peptide bonds.
-
DNA Polymerase
are enzymes that synthesize DNA molecules from deoxyribonucleotides, the building blocks of DNA.
-
Helicase
essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied.
-
Primase
enzyme that creates a primer on a DNA strand by adding RNA nucleotides to the strand according to the DNA template sequenc
-
Ligase
an enzyme that brings about ligation of DNA or another substance.
-
Topoisomerase
enzymes that participate in the overwinding or underwinding of DNA.
-
Gyrase
enzyme within the class of topoisomerase that relieves strain while double-stranded DNA is being unwound by helicase
-
Telomere
distinctive structures found at the ends of our chromosomes
-
Splicing
involves the removal or "splicing out" of certain sequences referred to as intervening sequences, or introns
-
Anti-Codon
a sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA.
-
Mitosis
a type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
-
meiosis
type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells
-
binary fission
type of asexual reproduction in prokaryotic cells an adult cell splits in half creating two new cells
-
G1
S
G2
Prophase
Prometaphase
metaphase
anaphase
telophase
cytokinesis
stages of Cell Cycle
-
interphase
the resting phase between successive mitotic divisions of a cell, G1, S, and G2 phases happen in this cell phase
-
prophase
first stage of cell divisions, during which the chromosomes become visible as paired chromatids and the nuclear envelope disappears
-
Prometaphase
second phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells, nuclear envelope breaks down
-
Metaphase
3rd stage in mitosis the chromosomes, guided by the spindle fibers, line up in the middle of the dividing cell.
-
Anaphase
4th phase of mitosis, spindle apparatus pulls the two chromatids of each chromosome apart and drags them toward opposite poles of the cell.
-
Telophase
fifth and final phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells.
-
Cytokinesis
physical process of cell division, which divides the cytoplasm of a parental cell into two daughter cells, happens at the end of mitosis or meiosis
-
centrosome
organelle that serves as a microtubule organizing center during division. It's duplicated during S phase, and the two copies move to opposite sides of the cell.
-
mitotic spindle
The spindle apparatus is the collective term for all the spindle fibers that form during mitosis or meiosis. These spindle fibers are responsible in moving and segregating the chromosomes during nuclear division.
-
Homologous chromosomes
one of the pair is from mother other father. The maternal and paternal chromosomes in a homologous pair have the same genes at the same loci, but possibly different alleles.
-
Autosomes
any chromosome that is not a sex chromosome
-
gametes
a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
-
Zygote
a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.
-
haploid
(of a cell or nucleus) having a single set of unpaired chromosomes.(of an organism or part) composed of haploid cells.
-
diploid
) containing two complete sets of chromosomes, one from each parent.
-
Non-Disjunction
the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei
-
RNA-induced silencing complex, or RISC
is a multiprotein complex, specifically a ribonucleoprotein, which incorporates one strand of a single-stranded RNA (ssRNA) fragment, such as microRNA (miRNA), or double-stranded small interfering RNA (siRNA).
|
|