HH
Monozygoitc (identical) twins always have the same blood type, so concordance value for this trait is
100%
By the end of the ____________ trimester of pregnancy, all major organ systems have formed.
1st
Out of every 4 people who have dominant allele for a particular gene, only 1 actually shows the dominant phenotype. Therefore, this allele has a penetrance of
25%
Mitochondrial DNA contains about how many genes?
37
An average woman releases about ________ oocytes during the reproductive years of her life.
450
A gene is located on the p arm of chromosome 8, in the 3rd region and 5th band within that region. What is its chromosomal "address"?
8p3.5
How many chromosomes are in a human tetraploid cell?
92 chromosome
a condition called ___________ results in an XY individual that produces testosterone, but doesn't have any testosterone receptors on their cells, and thus is pheotypically female.
Androgen insensitivity
One difference between AMNIOCENTESIS and chronic villus sampling (CVS) is that:
CVS can be done earlier in the pregnancy than amniocentesis
Are traits with many different phenotypes likely to be classified as continuous or discontinuous?
Continuous
___________ syndrome is caused by a deletion in the short arm of chromosome 5, resulting in intellectual disability, and an abnormal larynx causing cat-like cry.
Cri Du Chat
_________ twins originate from two separate fertilization events
Dizygotic
The only autosomal aneuploidy that allows survival into adulthood, but rarely past age 60, is:
Down syndrome (trisomy 21)
Because males have only one X chromosome, they are said to be _______________ for all the genes on the X
Hemizygous
Amniocenesis is the process of collecting cell from fluid surrounding a fetus in order to prepare a:
Karyotype
Phenotypic sex of a fetus with the sex chromosomes XYY is almost always:
Male
The theory that a uterus of an older mother is less efficient at rejecting abnormal embryos is known as:
Maternal selection
Female mammals are actually _________, comprised of two different cell types: some with their mother's X chromosome active, and some with their father's X chromosome active.
Mosaics
Female duct
Mullerian duct
_________ (NDJ). which usually occurs during anaphase of meiosis I or II, results in an embryo that is either trisomic or monosomic.
Nondisjunction
__________ is an online database with detailed information on over 10,000 inherited traits.
OMIM
Caster Semenya, the Olympic runner is from what country?
South Africa
The risk for Down syndrome increases when:
The mother is over thirty-five years old
In examining a karyotype, chromosome 2 and 7 are found to have exchanged segments. This individual has a structural change in his chromosomes known as a:
Translocation
What disorder is NOT usually associated with intellectual disability?
Turner Syndrome
Male duct
Wolffian duct
A chromosome whose centromere is very close to one end is called an
acrocentric chromosome
on a threshold model graph, are individuals in the shaded area of the curve affected or unaffected by the trait in question?
affected
a fetus's exposure to _______ is the leading preventable cause of birth defects worldwide.
alcohol
Polyploidy (such as triploidy or tetraploidy) is characterized by:
an increase in the number of chromosome sets
Y-linked traits are:
carried only by males and transmitted only to males
Camptodactyly A. causes bent, immobile little fingers B. is inherited as a dominant trait C. shows less than complete penetrance D. shows varying expressivity E. all of these
causes bent, immobile little fingers
_________ sex is determined at the moment of fertilization
chromosomal
Hemophilia
defects in blood clotting
Mendel's P1 pea plants with either short or tall phenotypes, displayed:
discontinuous variation
Most triploid zygotes are probably caused by:
dispermy
If concordance value for a trait in monozygotic twins is less than 100%, what accounts for the difference?
environmental factor
Female gametes complete meiosis II at:
fertilization
Human sex ratio at __________ is about 1:1
fertilization
If a trait has the heritability of value of 0.75, this indicates that 75% of the phenotypic variation in the trait is caused by:
genetic factors
A Barr body is a(n):
inactive X chromosome
A blastocyst:
is the stage of an embryo that implants in the endometrium
Deletion of an entire autosome:
lethal
Chromosomes are usually arranged in a karyotype and photographed during what stage of mitosis?
metaphase
Chromosomes whose centromeres are centrally located are classified as:
metracentric
The long arm of a chromosome is called the ________ arm.
q
Live-born infants with abnormal chromosome numbers who have the most normal phenotype and best chance at survival past the first year of life are more apt to have the ______________ involved than any other.
sex chromosomes
Any environmental agent that causes developmental disabilities in an embryo or fetus is a:
teratogen
In a structural change called a(n) ___________, two non-homologous chromosomes exchange parts and no genetic information is gained or lost
translocation (reciprocal)
A condition in which both copies of a chromosome are inherited from on parent is called:
uniparental disomy
The duct for the transport of sperm between a testis and the urethra is the:
vas deferans