Meiosis
23 is the magic number, not just for LeBron James or Michael Jordan, but also for the chromosomes in this classification of human gamete cells.
What is haploid?
The fundamental repeating unit of chromatin, the nucleosome core particle, consists of approximately 146 to 147 base pairs of DNA wrapped 1.65 times around an octamer of these specific proteins.
What are histones?
Monosomy X results in this chromosomal disorder.
What is Turner Syndrome?
This phenomenon describes the increased likelihood of chromosomal disorders in children of older mothers.
What is maternal age effect?
A limitation of this type of chromosome analysis cannot detect low-level mosaicism (<10-20%).
What is CMA?
Recombination, or crossing over, occurs in all normally functioning meiotic divisions, but moreso particularly near these parts of the chromsomes.
What are telomeres?
Histone acetyltransferases (HATs) neutralize the positive charge on lysine residues of N-terminal histone tails, shifting condensed heterochromatin into this transcriptionally accessible chromatin state.
What is euchromatin?
Classically characterized by a cleft lip and intellectual disorder, this condition is caused by a trisomy of chromosome 13.
What is Patau syndrome?
Not to be confused with chimerism, which is commonly due to fusion of two zygotes to form one embryo, this consequence of mitotic nondisjunction results in 2 or more genetically distinct populations of cells derived from one egg.
What is mosaicism
Only patient DNA are labeled and hybridized in this array of CMA.
What is SNP?
Unlike in male spermatogenesis, which produces 4 spermatozoa per meiotic division, female oogenesis produces only one ovum per division, in addition to 2~3 of these.
What are polar bodies?
Based on centromere position, human chromosomes with centromeres located so close to one end that the p arm consists only of stalks and satellites are designated by this term.
What are acrocentric chromosomes?
The most common type of triploidy, this describes the phenomenon of 2 paternal and 1 maternal copy of DNA.
What is diandric?
Nondisjunction during this process is least likely to yield a normal daughter cell.
What is meiosis I?
Benefits of this method include the ability to visualize structural abnormalities.
What is metaphase FISH?
Meiosis in males, creating mature sperm cells, has an average of this many chiasmata.
What is 50?
It may be difficult to distinguish the p arm from the q arm in this type of chromosome.
What is metacentric?
It is the standard cytogenetic notation for a male born with an extra X chromosome, commonly known as Klinefelter syndrome.
What is 47 XXY?
Errors in this process will result in detection of only two homologs, as opposed to three, when tested for molecular genetic polymorphic markers
What is meiosis II?
A limitation of FISH is that it cannot detect chromosomal gain/loss less than this number.
What is 100kb?
Also the average processing time for a US Passport renewal, the process of spermatogenesis, or producing new sperm cells, takes approximately this long.
What is 60-65 days?
Human telomeres protect chromosome ends from being recognized as double-strand breaks through tandem repeats of this specific 6-nucleotide DNA sequence.
What is TTAGGG?
Downs Syndrome, or Trisomy 21, is a chromosomal disorder that results in spontaneous abortion at a rate of this percentage.
What is 78%?
While many chromosomal defects result mostly from maternal nondisjunction, trisomy of this chromosome is ALWAYS due to maternal nondisjunction in meiosis I.
What is chromosome 16?
Pregnancy in women this age or older is a clinical indication for cytogenetic analysis.
What is 35?