Karyotype
___ no. pairs are sex chromosomes, or _______.
1 gonosomes
___ pairs homologous chromosomes are known as _____.
22 autosomes
G-bands are rich in ____, (dark stained bands) - especially _______.
AT heterochromatin
What is the most widely used banding technique?
G-banding
C-banding
Giemsa stain binds to constitutive heterochromatin, so it stains centromeres
5 different types of banding:
Q G R C T
Who described the first human chromosomes? When?
Walter Flemming 1879
___&____ chromosomes differ in ____ and _____ content, so they are _______ chromosomes.
X Y chromosomes size genetic non-homologous
Karyotype is :
a pictorial or photographic representation of all the different chromosomes in a cell of an indiv.
Position of G-bands: Each ___ is first divided into ___ and then identified by ____.
arm regions bands
Chromosomes are identified by ____ _____.
banding pattern
C-banding: Darker bands are generally found near _____ or ____. Dark regions are _____ regions while light are ______ regions.
centromeres telomeres heterochromatic euchromatic
What does word chromosome mean? (Waldeyer)
chroma-color soma-body
Human somatic cells contain ____ no. chromosomes, ___ no. pairs. The members of the pairs are ______ chromosomes.
diploid 23 homologous
Q-banding
fluorescent pattern obtained using quinacrine for staining. Pattern of bands similar to G
Gametes contain ____ no. chromosomes. Ovum contains ___ autosomes and __ no. ___ chromosomes. Sperm contain ___ autosomes and __ / __ chromosomes
haploid 22 1 X 22 X or Y
According to centromere position, chromosomes are classified as: (4)
metacentric submetacentric acrocentric telocentric
mFISH- what is it?
muticolour fluorescence in situ hybridization uses fluorescently labelled hybridization bonds
G-banding
obtained by trypsin treatment of chromosomes followed by Giemsa stain. Yields series of lightly and darkly stained bands.
Arm ratios are produced depending on : Shorter arm is shown ____ centromere and is called ___ _____ Longer arm is shown ____ centromere and is called __ _____
position of centromere above p arm below q arm
In Q-banding (prod. Casperson (1970)), for chromosomal staining he used _____ and obtained specific fluorescent light bands on chromosomes known as _______ (___-rich regions)
quinacrine q-bands AT
R-banding
reverse to G-banding. R-bands are guanine-cytosine-rich regions
In addition to a centromere, there may also be a ____ constriction on chromosomes. Often the part of centromere located distally to 2ndary const. is called _____ ______. They contain ____ that help organize or form the ______. (______ ________)
secondary chromosomal satellite genes nucleolus nucleolar organizer
Criteria for chromosomal arr.: 1 2 3
size of chromosome (largest to smallest) position of centromere banding pattern
Chromosome size:
varies
T-banding
visualizes telomeres