(M) Abrnormalities in Chromosomes Flashcards
senior-based transes
Changes resulting in a visible alteration of the
chromosome such as misrepair of broken bones, improper recombination or erroneous segregation during cell division can cause?
abnormalities
any exact multiple of the haploid
number of chromosomes (23) is called
euploid
T or F. Chromosome abnormalities lead to visible changes of the chromosomes
T
chromosome complements that are not exact multiples of 23
aneuploidy
T or F. Nondisjunction occurs when a HOMOLOGOUS pair of chromosome fails to disjoin or separate during cell division
T
identify each phase
1 is meiosis 1
2 is meiosis 2
3 is fertilization
4 is zygote
Nondisjunction during meiosis 2 produces daughter cells:
2 monosomic, 1 normal, and 1 no chromosome complement
if nondisjunction occus during meiosis 1, the meiosis 2 will produce?
2 daughter cells with 2 chromosomes
identify zygotes
2 zygotes with trisomy and 2 zygotes
with monosomy
identify zygotes
2 normal zygotes, 1 trisomic, and 1 monosomic zygote
T or F. A monosomic zygote is produced when there’s an extra chromosome.
F (2n-1 means there’s one less chromosome)
What phase does nondisjunction occurs?
1 and 2
what does it mean to have an extra chromosome (2n+1)?
Trisomic k beh
if nondisjunction occurs in meiosis 2, and
the daughter cells undergo fertilization, what you are going to produce are?
2 normal zygotes, 1 trisomic zygote, and 1 monosomic zygote (2:1:1)
Try to imagine what are the zygotes you will produce
If the nondisjunction occurs during meiosis 1 palang, one daughter cell will have an extra
chromosome and one with no chromosome complement
2 zygotes with trisomy and 2 zygotes
with monosomy
Identify what’s wrong with this
Oogenium -> primary spermatocyte -> 1 secondary oocyte and first polar body -> ootid -> 1 ova and 2 polar body
first correction: primary spermatocy should be primary oocyte
second correction: it will produce one mature egg cell and 3 POLAR bodies
just checking if familiar ka sa process ng gametogenesis
failure of the chromosomes to disjoin and pass to opposite poles
Meiotic Nondisjunction
T or F. 75% of meiotic nondisjuction occurs in OOGENESIS, where the probability of nondisjunction increases with maternal age
T
Almost how many % of meiotic nondisjunction occur in the first meiotic division?
80%
T or F. As men age, they have a higher likelihood of passing on genetic mutations to their offspring
T (4-5x increase mutation rate during
spermatogenesis because more cell division occur in the formation of sperm compared to oogenesis)
T or F. Babies who are born with younger father are prone to develop mendelian disorders due to a single gene mutation of large effects.
F (elderly father)
T or F. Increasing maternal age is associated with higher rate of mutation for Mendelian disorders during oogenesis in women.
F (increased naman ang nondisjunction)
What do u call when one homologous chromosome (meiosis) or chromatid (mitosis) lags behind and is left outside of the nucleus
anaphase lag
When chromosome/chromatid is lost, the gamete will fertilize and produce?
one normal cell and one monosomic cell
T or F. MONOSOMY involving an autosome generally represents loss of too much genetic materials to allow live birth or even embryogenesis, but a number of autosomal TRISOMIES do allow survival.
T
Anaphase Lag
The sister chromatids do not properly separate from each due to
Improper spindle formation
Anaphase Lag
During what phase will the chromatids will be left out of the cell membrane when the daughter chromosomes are formed?
Telophase
What is the chromosome that will be produced at the anaphase gap?
One will have monosomy and one will have a normal chromosome complement
T or F. The nomenclature of Chromosomes is described according to the IS for Human Genetic Nomenclature
F (Human Cytogenetic Nomenclature)
What describes the chromosomal
complement of an individual
Karyotype
T or F. In a karyotype, the total chromosome number is listed first,
followed by the sex chromosomes, and numerical and structural abnormalities and band location in DESCENDING order
F (ascend)
46,XX
babae
46,XY
bading
standard arrangement of a photographed or imaged stained metaphase spread in which the chromosome pairs are arranged in order of decreasing length
Karyotype
Part of a karyotype except:
A. Total number of chromosomes
B. Instertitial complement
C. Sex chromosome complement
D. Information on the Abnormality
B (imbento ko lang ‘ya)
the q arm stands for
long arm
the p arm stands for
short arm
when abnormalities occur after conception
mosaicism
i/iso
isochromosome
what does (-) and (+) mean
loss and gain
what does (r) mean
ring chromosome
what does (rcp) mean
reciprocal
what does (rob) mean
robertsonian translocation