okazaki fragment
tRNA
reads mRNA to be complementary to it. (3' -5') -90 nucleotides long. -undergoes POST-TRANSCRIPTIONAL MODIFICATION -raw tRNA contains introns which must be excised Functions: 1. Covalently Bonds to its specific A.A. at one end (CCA stem) with amino acid -acyl tRNA synthetase 2. Conects to ribosomes 3. Base pairs w/ mRNA (codon; tRNA= anti codon)
rRNA
ribosomal RNA; type of RNA that makes up part of the ribosome. "workbench"
intron
sequence of a eukaryotic gene's DNA that is not translated into a protein. CALLED SPACERS
Primer
strand of nucleic acid that serves as starting point for DNA synthesis on lagging strand
chromosome
a single package of DNA that contains many genes, regulator elements and other nucleotide sequences including HISTONE PROTEINS.
DNA polymerase III
adds nucleotide, only in 5' - 3' direction (can add only)
Holandric Traits
carried only on the Y chromosome
Bar Bodies
number of X chromosomes minus 1
Okazaki fragment
A short segment of DNA synthesized on a template strand during DNA replication. Many Okazaki fragments make up the lagging strand of newly synthesized DNA. 100-200 nucleotides long in Eukaryotes.
Start Codon
AUG = methionine
Pre Natal Diagnosis (birth defects)
Amniocentesis- 14th to 16th week gestation Chronic Villi Method- 10th to 12th week of gestation. Risk of spontaneous abortion=1%
transcription
(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA.
translation
(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm
Aneuploidy
Cells that have extra chromosomes or chromosomes missing. Monosomy (2n-1) =45 chromosomes Trisomy (2n+1) 47 chromosomes
mRNA
Messanger RNA. messanger from DNA to cytoplasm to make polypeptides (amino acid sequences). (mRNA= 5' to 3')
Translocation
Ribosomes move 3 nucleotides to the right along the mRNA. mRNA moves through the groove between the two sub units like a tape recorder. Movement is really dependent upon random motion and accidental, but predictable collisions.
Stop Codons
UAG, UGA, UAA
