Ch. 30 Chromosomal Abnormalities Flashcards
(114 cards)
_______are the structures, located in each cell in our body, that hold our genes.
Chromosomes
an error in either the number or structure of chromosomes
chromosomal abnormality
The normal cell has ____chromosomes or two pairs of ____.
46; 23
_______ is a condition in which there are an abnormal number of whole chromosomes. Specifically, an aneuploid has too many or too few chromosomes.
Aneuploidy
chromosomal aberration in which there is a third chromosome 18
Edwards syndrome
a cell having three copies of an individual chromosome
trisomy
Turner syndrome, also referred to as _______ X, is a different type of chromosomal abnormality in which the fetus has only one sex chromosome.
monosomy
a chromosomal aberration where one sex chromosome is absent; may also be referred to as monosomy X
Turner syndrome
_______ and ______ have been suspected to increase the likelihood of chromosomal abnormalities.
Environmental factors; maternal age
is a structural feature that differs from the norm. An example of an ______ is agenesis of the corpus callosum in which there is congenital absence of an important midline brain structure.
anomaly
the congenital absence of corpus callosum that may be partial or complete
agenesis of the corpus callosum
a group of clinically observable findings that exist together and allow for classification. These signs and symptoms are linked to each other in some way.
syndrome
_______has clinically identifiable signs such as a flat facial profile and a transverse crease in the palm of the hand. An example of symptoms of _______would be developmental delays and hearing loss.
Down syndrome
a structural abnormality that results from an abnormal development
malformation
_________is a congenital brain malformation that is thought to be caused by a developmental deviation in the roof of the fourth ventricle.
Dandy–Walker malformation
congenital brain malformation in which there is enlargement of the cisterna magna, agenesis of the cerebellar vermis, and dilation of the fourth ventricle
Dandy–Walker malformation
The three laboratory values that typically comprise the triple screen are ______, _______, and ______.
MSAFP, estriol, and hCG.
AFP is produced in the ______and fetal liver. Estriol and hCG are produced by the _______.
yolk sac; placenta
This simple blood test can reveal gender and is also highly accurate in detecting chromosomal anomalies, including trisomies 21, 18, and 13 and sex chromosome abnormalities, as early as 9 weeks’ gestation.
cell-free DNA testing
the most common cause of abnormal serum screening tests is _______ of the pregnancy.
incorrect dating
Advanced maternal age is considered to be ______ years or older.
35
an analysis of fetal chromosomes; reveals the morphology and number of chromosomes
Fetal karyotyping
the form and structure of an organism
morphology
During pregnancy, a sample of maternal blood, amniotic fluid, or tissue from the placenta can be used for fetal karyotyping. There are three main procedures used to obtain material for fetal karyotyping: ______,_______,_______
(i) chorionic villi sampling (CVS), (ii) amniocentesis, and (iii) cordocentesis