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DNA Ligase ---- an enzyme that connects (ligates) two strands of DNA (Okazaki fragments on the lagging strand)
DNA Helicase ---- an enzyme that separates the two strands of the double helix to allow replication
alleles ---- variant versions of a gene (each human has only two copies but more versions can exist within a population)
hydrophobic ---- does not mix with water (non-polar)
hydrophillic ---- mixes with water (polar)
fluid mosaic model ---- a model that describes the cell membrane as a continually moving and dynamic mixture of proteins and phospholipids
integral protein ---- a protein that is at least partially embedded inside the cell membrane
peripheral protein ---- a protein that is attached to but not inside the cell membrane
transmembrane protein ---- a protein that extends through both sides of the plasma membrane
passive transport ---- the transport of molecules through channel proteins requiring no energy input
active transport ---- the transport of molecules through channel proteins requiring an input of energy
diffusion ---- the natural movement of molecules from an area of high concentration to an area of low concentration
osmosis ---- the movement of water through a semi-permeable membrane from an area of low solute conentration to an area of high solute concentration
hypotonic ---- a solution with a low solute concentration (high water concentration) in comparison to a second solution separated by a semi-permeable membrane
hypertonic ---- a solution with a high solute concentration (low water concentration) in comparison to a second solution separated by a semi-permeable membrane
channel proteins ---- transmembrane proteins that create a pore spanning the cell membrane and allow specific molecules to cross
carrier protein ---- a protein that aids the transport of a small molecule from one side of the cell membrane to the other
facilitated diffusion ---- the movement of molecules down a concentration gradient (in the direction of diffusion) aided by a carrier protein
uniport ---- the facilitated transport of one molecule across a cell membrane
symport ---- the facilitated transport of two molecules across a cell membrane
antiport ---- the facilitated transport of two molecules across a cell membrane at the same time and in opposite directions
Gregor Mendel ---- an austrian monk who experimented with pea plants in the 19th century and provided the first detailed experiments of how traits are passed down from an individual to their offspring
unit factors ---- Mendels original term for genes
Independent Assortment ---- genes (unit factors) for different traits are randomly sorted into gametes
dominant ---- a trait or gene which is expressed even if only one copy is present
recessive ---- a trait or gene which is expressed only if two copies (both alleles) are present
Mendels Postulates ---- 1) Unit factors Exist in Pairs 2) Dominant / Recessive 3) Segregation 4) Independent Assortment
wild type ---- the normal or most commonly occuring version of a gene
transcription ---- the process of a cell making RNA from DNA
translation ---- the process of a cell making protein from RNA
central dogma ---- the concept of DNA being transcribed to RNA which is translated into protein
ribose ---- a 5 carbon sugar that is a building block of RNA nucleotides
uracil ---- a nucleotide that is part of RNA instead of thymine which is a part of DNA
mRNA (messenger RNA) ---- RNA that codes for protein
AUG ---- the standard translation start codon which codes for methionine
codon ---- a three nucleotide segment of mRNA that codes for an amino acid
anti-codon ---- the part of tRNA that binds to the codon of mRNA
ribosome ---- a large complex made of RNA and protein where translation occurs (where proteins are made)
chromosome ---- a relativley large segment of DNA containing many genes
DNA Polymerase ---- an enzyme that adds nucleotides to the growing DNA strand
DNA Gyrase ---- an enzyme that releases tension in the double helix as the two strands are unwound during replication
Okazaki fragment ---- a small segment of DNA that is produced on the lagging strand during replication
Leading Strand ---- the strand that is replicated continuously since it is synthesized in the same direction that the replication fork opens
Lagging Strand ---- the strand that is replicated discontinuously in small segments called Okazaki fragments
Primase ---- an enzyme that adds the RNA primer necessary for replication to proceed
Primer ---- a short strand of RNA that must bind to the template strand in order for DNA Polymerase to begin replication
phenotype ---- the characteristic that can be seen (caused by an underlying genotype)
genotype ---- the underlying genes that an organism has that causes the phenotype being observed
locus ---- the location of a gene on a chromosome
codominance ---- when two alleles can both be expressed, neither is dominant to the other (like A and B in human blood types)
homozygous ---- when an individual has two copies of the same allele
heterozygous ---- when an individual has two different alleles at a gene locus
meiosis ---- the process that produces haploid reproductive cells in eukaryotes
mitosis ---- the process by which a eukaryotic cell replicates its DNA and divides into two identical cells
prophase ---- the first phase of mitosis where the nuclear envelope breaks down, centrioles move to opposite poles and chromosomes condense
metaphase ---- the state of mitosis when the centromeres of each chromosome have reached the center of the cell
anaphase ---- the stage of mitosis when sister chromosomes are being pulled to opposite poles by the spindle fibers
telophase ---- the phase of mitosis when the nuclear enelope begins to form and spindle fibers break down right before cytokinesis
kinetochore ---- the protein structure that forms on top of each centromere and to which the spindle fibers connect
centromere ---- the region of the chromosome that the spindle fibers (and kinetochore) attach to
chromosome ---- the large structures made of DNA and histone proteins which contain many genes that carry the hereditary information
chromatin ---- the term for chromosomes when they are relatively unwound and less visisble during interphase
centrosome ---- the region where the centrioles are located
centrioles ---- the cellular structures which spindle fibers attach to at opposite poles of the cell
interphase ---- the portion of the cell cycle when the cell is not going through mitosis or meiosis
S phase ---- the portion of interphase when the chromosomes (DNA) are being replicated
chiasma ---- the structures visible where homologous chromosomes have crossed over
crossing over ---- a process where homologous chromosomes swap portions of similar DNA through recombination
synaptonemal complex ---- a structure which forms between homologous chromosomes during Prophase I of Meiosis
Meiosis I ---- the portion of Meiosis when homologous chromosomes pair, cross over and then separate to opposite poles
terminalization ---- when the chiasma move towards the end of the chromosomes (near the completion of Prophase I of Meiosis)
sister chromatids ---- the copies of each chromosome which are paired at the centromere during Meiosis and Mitosis
homologous chromosomes ---- pairs of chromosomes which exist in any diploid cell that have the same genes (but possibly different versions or alleles)
Mycobacterium tuberculosis ---- the bacteria that causes Tuberculosis
Bordetella pertussis ---- the bacteria that causes Whooping Cough
Mycobacterium leprae ---- the bacteria that causes Leprosy
Borrelia bugdoferi ---- the bacteria that causes Lyme Disease
Yersinia pestis ---- the bacteria that causes the Plague
Vibrio cholerae ---- the bacteria that causes cholerae
Vibrio vulnificus ---- the bacteria that causes shell fish poisoning
Bacillus anthracis ---- the bacteria that causes Anthrax
Chlamydia trachomatis ---- the bacteria that causes Chlamydia
Staphylococcus aureus ---- a bacteria that causes skin infections
Corynebacterium diptheria ---- the bacteria the causes diptheria
Helicobacter pylori ---- the bacteria that causes ulcers
Neisseria gonorrhoeae ---- the bacteria that causes Gonorrhea
Salmonella typhi ---- the bacteria that cause Typhi
Rickettsia rickettsii ---- the bacteria that causes Rocky Mountain Spotted Fever
Treponema pallidum ---- The bacteria that causes Syphilis
Clostridium botulinum ---- the bacteria that causes Botulism
p arm ---- the short arm of the chromosome (the chromosome is divided in two regions by the centromere)
q arm ---- the long arm of the chromosome (the chromosome is divided in two regions by the centromere)
nucleus ---- where DNA is stored
mitochondria ---- the powerhouse of the cell where ATP is produced
chloroplast ---- an organelle in plant cells where photosynthesis occurs
centriole ---- the structure that spindle fibers attach to during mitosis and meiosis
nucleolus ---- in prokaryotes the region where the chromsome is located
endoplasmic reticulum ---- the transport network for molecules within the cell
golgi apparatus ---- the organelle that packages proteins and lipids for export from the cell
ribosome ---- a large complex made of protein and DNA where proteins are made (translated)
centrosome ---- a structure composed of two centrioles involved in the formation of the mitotic spindle
vacuoles ---- structures that store food and waste