(M) Cytogenic techniques (manual based) Flashcards
study of the physical size and structure of chromosomes
cytogenetics
A specialized laboratory discipline that examines the structure and behavior of chromosomes at the cellular level
cytogenetics
Which phase is the best for studying the physical characteristics of chromosomes
cell cultures that are halted near metaphase
why are cell cultures halted near metaphase the best for studying the physical characteristics of chromosomes
chromosomes are most compact
what are the chromosomes stained in the form of?
(cell cultures haltd near metaphase)
dyads or bivalent
study of ______ _______ ______ and number can be vital for understanding a variety of genetic abnormalities that are produced by mutations that alter chromosomes
normal chromosome structure
What are the two techniques used to visualize chromosome changes
- classical / standard cytogenic method
- Fluorescent in situ hybridization (FISH)
this method allows visualization of loss or gain of genetic material that contains at least 4 megabases of DNA
classical / standard cytogenic method
DNA needs to contain at least how many bases for standard cytogenetic method?
4 megabases
This is the gold standard in providing a whole genome scan
standard cytogenic method
What does classical cytogenetics require
viable, nucleated cells in cell cycle
how long are the nucleated cells cultured for classical cytogenetics?
one day to two or more weeks
T or F
All abnormalities can be detected using the classical cytogenetic technique as it has the best microscopic resolutions
F ( certain abnormalities may not be detected due to limitations in microscopic resolutions)
This visualization method allows much smaller changes in chromosomes to be seen
Fluorescent in situ hybridization (FISH)
What is the principal molecular technique currently used in the clinical lab?
Fluorescent in situ hybridization
What is the other name for FISH?
molecular cytogenetics
What was FISH originally developed for?
to enhance the resolution of chromosome observation
This is the complete set of chromosomes in the cells of an organism
Karyotype
how many somatic pairs of chromosomes do we have
22 pairs
how many pairs of chromosome do humans have in total?
23
how many pairs of sex chromosomes do we have?
one pair
T or F
Changes in karyotype is indifferent with the changes of the phenotype of the individual
F (it is correlated with the changes)
how are the different types of chromosomes distinguished?
using dyes
What do dark bands represent
heterochromatins