Turners syndrome xo females with turner syndrome are


Turner's syndrome (XO): Females with Turner syndrome are short in stature and have
a webbed neck . They might be infertile and have difficulty in mathematics, but their
verbal ability is often quite good.

Klinefelter syndrome (XXY):
10. Know percent of genetic relatedness among parent/child, sibs, grandparents, etc.
(lecture).

50% -parents

25%- grandparents
11. Know Gotlieb’s Epigenetic Theory (lecture, also p. 56).
 development is the result of an ongoing, bidirectional interchange between heredity and
the environment

 Genes do not dictate development; rather, they interact with each other, leading to
epigenetic effects where cell expression is turned on or off according to the
environments’ interaction with the given genes.
12. Define epigenetics.
13. Know the two mechanisms discussed in class: histone acetylation and DNA
methylation (lecture & p. 86).

Histone acetylation adds an acetyl tail to a clump of proteins (genes) that make it
unwind and easier to read – turning it ON.

Acetylation of histone proteins reduces the affinity between histones
and DNA. RNA polymerase and transcription factors then have easier to access
the DNA.

Therefore, in most cases,
 histone acetylation enhances transcription

histone deacetylation represses transcription.
18.
 DNA methylation does the opposite, by adding a methyl group to the cytosine base, it
represses transcription and turns it OFF.

DNA methylation is the addition of a methyl group (CH
3
) directly to the DNA's
cytosine base.
 It may affect gene transcription through several different mechanisms
(usually repression of transcription).

The methylation pattern is heritable after cell division.
 What is behavioral genetics (p. 54)?

Behavioral genetics is the field that seeks to discover the influence of
heredity and environment on individual differences in human traits and development
 Define and distinguish the different genotype/environment correlations: passive,
evocative, & active and show how the relative importance of the three types of interactions
may change with age (p. 54-57).
 Passive genotype-environment correlations: occur because biological
parents, who are genetically related to the child, provide a rearing environment for the
child.

Evocative genotype-environment correlations: occur because a child's
genetically influenced characteristics elicit certain types of environments

Active (niche picking genotype-environment correlations:

Prenatal diagnostic tests: ultrasound, amniocentesis, chorionic villus sampling
(CVS), maternal blood sampling & PGD and sex determination (p. 62-63)?

Ultrasound: the use of sound waves to scan the womb and create a visual
image of the fetus on a monitor screen
 Amniocentesis: Amniotic fluid is collected with a needle and analyzed for fetal
cells; risk of miscarriage is 1:3,600 (not safe until week 15)

Chorionic villus sampling (CVS): cells from the chorion are collectes, usually