HMX Genetics Practice Test Questions and Answers

HMX Genetics Practice Test Questions and Answers Variants - ANSWER Differences in DNA sequence -lead to changes in phenotype -can affect amount of RNA produced by affecting transcription, RNA stability, changing RNA levels -can affect amount of protein produced by affecting translation, protein stability, changing protein levels, protein function, etc. Single Nucleotide Variance (SNV) - ANSWER differences in DNA sequence at one location Single Nucleotide Polymorphisms - ANSWER common SNVs that occur in more than 1% of the population 2% of genomic DNA encodes the... - ANSWER ~20,000 protein coding genes DNA - ANSWER -subunits = nucleotides -deoxyribose sugar (3'), phosphate group (5'), nitrogenous base - right handed, double stranded, helix - connected by bases via hydrogen bonds; strands are complementary -written 5' to 3' 4 Nucleotides in DNA - ANSWER adenine, guanine, cytosine, thymine A double H bond to T C triple H bond to G Average size of a human gene - ANSWER 8,500 bases in length (8.5kb) Coding Strand - ANSWER the strand of DNA that is not used for transcription and is identical in sequence to mRNA, except it contains uracil instead of thymine Chromatin - ANSWER DNA wrapped around histone proteins creating a nucleosome -150 bps wound around histones, many nucleosomes in gene -chromatin can be modified by chemical groups to determine how tightly DNA is packed in a region Central Dogma - ANSWER DNA - RNA - Protein -information -- portability -- structure/function -DNA is transcribed into RNA, RNA is translated into proteins RNA characteristics - ANSWER uses ribose sugar, single stranded, bases: A, G, C, U (uses uracil), travels into the cytoplasm from nucleus Pieces of a gene in transcription - ANSWER Enhancer - upstream of promoter/gene, transcription factor site Promoter - directly upstream of gene body to be translated, transcription factor site Transcription Start Site - where transcription will begin on gene body, 3' end of promoter and ends at 5' end of terminator Gene Body - gene to be transcribed Terminator - instructions to stop transcription RNA Polymerase II - transcribes template strand into RNA, mediates transcription