CH 6 - BIO
DNA - Lives in nucleus; All living organisms got it in almost all cells of body; Has instructions for functions of cell; Serves as individual identifier.
TWO Features of DNA - DNA is passed from parent to baby; Got instructions for making body, controlling growth, development, and behavior
Double Helix - Two sugar phosphate backbones that spiral each other, forming structure of DNA. Connected by bases sticking out of sugar molecules.
Nucleotide - Unit of DNA molecule has three parts; phosphate group, a sugar, and nitrgoen containing base.
Base Pairs - Connected by hydrogen bonds
Gene - Specific sequence of DNA
Locus - Location of gene on a chromosome
Chromosome - One or more unique pieces of DNA
Genome - An organism’s complete set of DNA
Alleles - Different versions of a gene that code for the same trait Ex: Same flower being different colors
Trait - Any single characteristic or feature of an organism
Bacteria and Viruses - Genes make up 90% or more of DNA
Eukaryotes (Except Yeast) - Have a big amount of non-coding DNA
Introns - Noncoding regions within genes;
Noncoding DNA - Pretty useless but can help with gene regulation
Exons - Coding region of DNA
Transcription - A copy of a gene’s base sequence is copied from DNA to go between mRNA
Translation - The copy of transcription is used to direct the production of a polypeptide
Step 1 of Transcription - Recognize and Bind; RNA finds promoter site at beginning of gene and binds to it, unravels it to a single strand and starts reading that hoe.
Step 2 of Transcription - Transcribe: RNA polymerase processes the DNA and then builds a copy of it, like a TRANSCRIPT, called mRNA and that bitch is now free to move around the cell and share it’s message to maybe make a protein
Step 3 of Transcription - Terminate: RNA polymerase finds a code signaling the end of a gene, UAA, UAG, and UGA, and stops translation and release the mRNA transcript
Final Step of Transcription - Cap + Edit: mRNA gets cap and tail to protect it and make it recognizable and in final check, noncoding sections are removed from that bitch YUH
mRNA - “Middle Man” that reads and sends information
Transfer RNA (tRNA) - Molecule that translates mRNA by linking specific bases on the mRNA with specific amino acids that will be used to build a PROTEIN
Anti-Codon - THREE base sequence that attaches to mRNA’s three bases a.k.a CODON
Codon - THREE base sequence that matches up with an anti-codon
Translation - Copy of transcription is used to direct the making of a polypeptide that will then be folded into a PROTEIN. Needs LOTS of amino acids and ribosomal units
Step 1 of Translation - Recognize and Start Protein Building; Starts in CYTOPLASM; Start sequence of mRNA is recognized by the corresponding tRNA molecule and two ribosomal subunits. tRNA attaches to mRNA while the ribosomal units assemble around them!
Step 2 of Translation - Elongate; As the ribosome moves along the mRNA strand, each new amino acid carrying tRNa molecule binds to the next three bases on the mRNA. After ribosomes help amino acids attach to each other, the tRNA’s just drop off and the amino acid chain grows like a beaded bracelet! YUH
Step 3 of Translation - Terminate; Once ribosome finds the three base STOP sequence, protein assembly is complete PERIODT. Both protein and mRNA are released from the ribosome!
mRNA molecule can… - BE translated over and over again until that bitch disintegrates
Mutation - An alteration to the sequence of bases in DNA; Can be very bad or rarely good (like X-men); Essential to EVOLUTION
Neutral Mutations - Have no positive or negative effect on organism
Non-Sex Cell Mutation - Can have BAD consequences on person carrying them; NOT passed on to offspring
Sex Cell Mutation - No bad effects on person carrying them; CAN be passed to offspring
Point Mutation - Happens when one base pair is SUBSTITUTED for another, or base pair is INSTERTED or DELETED. VERY HARMFUL; Nucleotide substitution, insertion, deletion
Chromosomal Aberrations - Changes to the overall organization of genes. The deletion of an ENTIRE section of DNA or RELOCATION of a gene in the same gene or a completely different one
Spontaneous Mutation - Arises by accident during DNA replication
Radiation-induced Mutation - Like x-rays, which have the power to disrupt atomic structure, even break apart chromosome, by removing tightly bound ELECTRONS
Chemical-induced Mutation - Chemicals like those in vapes and cigarette can also react with atoms in DNA and cause mutation
Path from Mutation to Illness? - Mutated gene codes for a nonfunctioning protein (usually an enzyme), Nonfunction enzyme can start reactions like it usually would, molecule that would have typically been changed from the reaction starts to build in the cell, the accumulating chemical causes ILNESS or DEATH
Tay - Sachs Disease - Lysosome storage disorder causes by a faulty Chromosome 15
Gene Regulation - When gene is turned on or off to regulate itself
Microarray - Small chip that looks like microscope slide used to monitor the level of thousands of genes.
Protein Synthesis - Process of linking together amino acids with help of mRNA strand
Genotype - Genes an organism carries for a particular trait
Phenotype - Physical expression of genotype of organism