An enzyme that untwists the double helix at the replication forks, separating the two parental strands and making them available as template strands
An enzyme that joins RNA nucleotides to make the primer
Single Strand Binding Protein
(SSB Protein) A protein that binds to the unpaired DNA strands during DNA replication, stabilizing them and holding them apart while they serve as templates for the synthesis of complementary strands of DNA
DNA Polymerase 1
Clears away RNA primers (using 5' to 3' activity) and synthesizing new DNA in these gaps
DNA Polymerase 3
Enzyme that builds new DNA strands. it could only be done in one way (5' to 3')
An enzyme that connects two fragments of DNA to make a single fragment; also called DNA ligase
Physiological feature, bodily characteristic, behavior, or outward appearance of an organism
The genetic makeup of an organism
Trait that will only appear in the phenotype if organism inherits two of them; covered up by the dominant gene
Observed trait of an organism that masks the recessive form of a trait
Having two identical alleles for a trait (YY, yy)
Having two different alleles for a trait (Yy)
A portion of DNA that has information that is used to make more of a protein
Alternate forms of a gene
A characteristic that an organism can pass on to its offspring through its genes.
Transfer RNA; type of RNA that carries amino acids to the ribosome
Messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome
The most abundant type of RNA, which together with proteins, forms the structure of ribosomes. Ribosomes coordinate the joining of tRNA molecules to mRNA codons.
AUG, signals the start of translation
UAA, UAG, and UGA, that indicate the point at which mRNA translation is done
In initiation, an enzyme (RNA Polymerase) unwinds the double helix of DNA and the nucleotides of DNA pair with the nucleotides of RNA
Elongation occurs when the RNA polymerase continues to move along the DNA and the mRNA lengthens.
Termination occurs when the RNA polymerase runs out of DNA to copy. The mRNA is released from the enzyme and the RNA polymerase detaches from the DNA.
Translation is the process by which information is encoded in the messenger RNA and is used to assemble a protein at the ribosome.
Transcription is the process by which the genetic information encoded in DNA is copied onto messenger RNA.
A small subunit attaches to an mRNA molecule (from transcription). A tRNA molecule binds to a specific codon sequence (ACUG) on the mRNA. The large subunit then joins the complex. tRNA is now in a binding site called the P site.
When a new tRNA fits into a codon on the mRNA, it attaches to the A site. Peptide bonds form, connecting the two amino acids and disconnecting the tRNA and the amino acid. The tRNA in the P site moves onto the E site, and the tRNA in the A site is moved to the P site.
The ribosome then comes to a codon that signals that the protein is finished. The protein (polypeptide chain) is released from the tRNA molecule and the ribosome splits back into the large and small subunits.
Group of three bases on a tRNA molecule that are complementary to an mRNA codon
a specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid
breeding for difference in one trait
Spectrum of dominance
different levels of being dominant or recessive in comparison to two different alleles of a gene
a condition in which a trait of an individual is intermediate between the phenotype of the individual's two parents because the alleles aren't dominant or recessive to one another
a relationship in which one allele is completely dominant over another
A phenotypic situation in which the two alleles affect the phenotype in separate, distinguishable ways
three or more alleles that exist for a single gene; ex. the possible blood types are A, B, AB, and O
positive blood type
dominant over negative, (has a rh integral protein that lies on the surface of the red blood cell)
O blood type
doesn't create A or B antigens (inactive)
Occurs when a group of gene pairs acts together and produces a specific trait, such as human eye color, skin color, or height
specific locations of genes along the chromosome (have to look at multiple chromosomes to determine eye color, skin color, hair color, ect.)
any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions
macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes
molecule composed of carbohydrates and fats
a deficiency of red blood cells
the light-sensitive membrane covering the back wall of the eyeball
a deficiency of red blood cells
a diagram that shows the occurrence of a genetic trait in several generations of a family
mutation of HTT gene, which is in charge of making a protein called Huntington (interaction with nerve cells in the brain).
autosomal dominant, meaning not on the 23rd chromosome and needing only one copy of the gene needs to be passed down to contract the disease
clumsiness, jaw clenching, slurred speech, uncontrolled muscle movements, and delusions.
medication for movement problems and depression, no cure
all the other genes in the body that are not sex-linked, any chromosome that is not a sex chromosome
Huntington's (life expectancy)
about 15 years after diagnosis, most die from complications of the disease, not the actual disease
missing enzyme HEXA (CHROMOSOME 15) breaks down ganglioside (formation of nerve cells), when ganglioside can't be broken down it builds on nerve cells (can head to paralysis)
recessive autosomal, not on the 23rd chromosome and both parents need to be carriers
red dot in retina, deterioration of motor skills, speech and swallowing difficulties, becoming blind or deaf
no cure, only supportive care
Tay-Sach's (life expectancy)
about 4 years
Cystic Fibrosis (why)
caused by a defective gene, causes body to produce abnormally thick and sticky mucus, builds up in the lungs
Cystic Fibrosis (what)
recessive autosomal, not on the 23rd chromosome and both parents must be carriers
Cystic Fibrosis (symptoms)
fever, increased coughing, increased shortness in breath, loss of appetite, more sputum (mucus that is coughed up from lower airways)
Cystic Fibrosis (treatment)
no cure, antibiotics, inhaled meds, salt solution, flu and PPV vaccine, lung transplants, oxygen therapy
Cystic Fibrosis (life expectancy)
diagnosed as newborns, 1st birthday, diagnosed older, up to 37
Sickle cell anemia (why)
abnormal type of hemoglobin called hemoglobin S, which changes the shape of blood cells, into sickles. This prevents blood from clotting as easily, and also prevents against malaria (bacteria can't lay eggs in sickle shaped blood cells)
Sickle cell anemia (what)
recessive autosomal, inherit from both parents
Sickle cell anemia (symptoms)
pain, hand foot syndrome, frequent infection, delayed growth, vision problems
Sickle cell anemia (treatment)
no widespread cure, blood transplants, bone marrow transplants
Sickle cell anemia (life expectancy)
a phenotype of an allele related to the se chromosome of an individual (23rd chromosome)
Sex linkages causes
gender and a faulty 23rd chromosome
color blindness (what and where)
A decreased or complete inability to percieve different colors, on the X chromosome. Boys can get it if their mother or father is a carrier because they only have 1 X chromosme
Hemophilia (what and where)
A condition where the body has an inablilty to clot blood (lack of fibrin protein), on the X chromosomes, 3 types
hemophilia caused by a congenital deficiency of factor 8
a clotting disorder similar to hemophilia A but caused by a congenital deficiency of factor 9
Most mild type, deficiency of factor 11
Hemophilia (life expectancy and gender)
50-60 years, A and B only in males, C in both males and females
Duchenne Muscular Dystrophy (what and where)
A degenerative disease where muscles become weak to the point of immobility, on the X chromosome
why do people get dmd?
protein distrophin cannot be made due to mutation of the dystrophin gene
enlarged calf muscles and frequent falls, symptoms usually shown around age 5
DMD life expectancy
Symptoms present at 5, need braces to walk by 10, and by age 12 boy is usualy ina wheelchair. about 30 years (due to cessation of heart and lung muscles)
Who gets sex-linked diseases?
mainly boys, because the diseases are carried on the X chromosome.Girls have two X chromosomes, so if one is faulty, she will have another one to create proteins from, making her a carrier. Boys do not have the extra X, (they have XY), so any mutation in the X chromosome will be used to make proteins
individual who has one copy of the allele for a recessive disorder and does not exhibit symptoms, a person with a disease that they can pass on to other organisms
a ratio of what you can see to what you cannot see (brown eyes to blue eyes, 3:1)
the ratio of the genotypes that appear in the offspring
Sex-linked vs. Autosomal
Autosomal traits are inherited via genes that do NOT determine an individual's sex. Sex-linked traits, however, are inherited via genes that DO determine an individual's sex (X and Y chromosomes).
A picture of all the chromosomes in a cell arranged in pairs, display of a person's 46 chromosomes
a mishap when the members of a pair of chromosomes do not move apart properly during meiosis I (anaphase I) (no chance of survival) or sister chromatids fail to separate in Meiosis II (anaphase II) (50% chance of survival)
having an abnormal number of chromosomes
a cell that has 3 copies of a chromosome instead of the normal 2
a cell that has 1 copy of a chromosome instead of the normal 2
condition in which an organism has extra sets of chromosomes, it is the result of an accident during cell division
when a chromosome lacking a centromere is lost
Repetition of part of a chromosome resulting from fusion with a fragment from a homologous chromosome; can result from an error in meiosis
the maternal and paternal chromosomes, term used to refer to chromosomes that each have a corresponding chromosome from the opposite-sex parent
a chromosome rearrangement in which a segment of a chromosome is reversed end to end. occurs when a chromosome has breakage and rearrangement within itself.
a mutation that occurs when a piece of DNA is removed from one chromosome and attached to another chromosome
A mutation involving the addition of one or more nucleotide pairs to a gene.
Down syndrome (what)
genetic disorder when a person has 47 chromosomes instead of 46
Down syndrome (where)
extra copy of the 21st chromosome
Down syndrome (symptoms)
small/abnormally shaped head, excess skin on the back of the neck, flattened nose, single crease in the palm of the hand, small ears, small mouth, upward slanting eyes, and white spots on the iris