SLO's ch. 2 Flashcards
Describe how genes and chromosomes provide
our basic genetic endowment
A child receives 23 chromosomes from each parent. These
46 chromosomes provide the genetic blueprint that will
guide cell activity for the rest of the individual’s life.
Compare monozygotic twins with dizygotic
twins.
Monozygotic twins are twins who are genetically identical.
Dizygotic twins are two separate ova fertilized by two
separate sperm at roughly the same time.
Describe how the sex of a child is determined
When an ovum and sperm meet at the moment of fertilization,
the ovum provides an X chromosome, while
the sperm provides either an X or a Y chromosome. If the
sperm contributes its X chromosome, the child will have
an XX pairing and will be a girl. If the sperm contributes a
Y chromosome, the result will be an XY pairing—a boy
Explain the mechanisms by which genes
transmit information
A genotype is the underlying combination of genetic material
present in an organism, but invisible; a phenotype
is
the visible trait, the expression of the genotype.
Describe the field of behavioral genetics and
what it encompasses.
The field of behavioral genetics, a combination of psychology
and genetics, studies the effects of genetics on behavior
and psychological characteristics.
Explain what can happen when development
deviates from the norm.
Genes may become physically damaged or may spontaneously
mutate. If damaged genes are passed on to the child,
the result can be a genetic disorder
Describe the role of genetic counselors, and
differentiate between different forms of
prenatal testing
Genetic counselors use a variety of data and techniques to
advise future parents of possible genetic risks to their unborn
children. A variety of techniques can be used to assess
the health of an unborn child if a woman is already pregnant,
including ultrasound, CVS, and amniocentesis.
Explain how the environment and genetics work
together to determine human characteristics.
combination
of genetics and environment. Genetically based
traits represent a potential, called the genotype, which may
be affected by the environment and is ultimately expressed
in the phenotype.
Summarize how researchers study the
interaction of genetic and environmental
factors in development
To work out the different influences of heredity and environment,
researchers use nonhuman studies and human
studies, particularly of twins.
Explain how genetics and the environment
jointly influence physical traits, intelligence,
and personality
Virtually all human traits, characteristics, and behaviors are
the result of the combination and interaction of nature and
nurture. Many physical characteristics show strong genetic
influences. Intelligence contains a strong genetic component
but can be significantly influenced by environmental
factors. Some personality traits, including neuroticism and
extroversion, have been linked to genetic factors, and even
attitudes, values, and interests have a genetic component.
Some personal behaviors may be genetically influenced
through the mediation of inherited personality traits.
Explain the role genetics and the environment
play in the development of psychological
disorders
Certain psychological disorders, such as schizophrenia, are
largely caused by genetics. Other disorders, including alcoholism
and major depressive disorder, have both genetic
and environmental causes.
Describe ways in which genes influence the
environment.
Children may influence their environment through genetic
traits that cause them to construct—or influence their parents
to construct—an environment that matches their
inherited dispositions and preferences
Explain the process of fertilization
When sperm enter the vagina, they begin a journey that
takes them through the cervix, the opening into the uterus,
and into the fallopian tube, where fertilization may take
place. Fertilization joins the sperm and ovum to start prenatal
development.
Summarize the three stages of prenatal
development
The germinal stage (fertilization to two weeks) is marked
by rapid cell division and specialization, and the attachment
of the zygote to the wall of the uterus. During the
embryonic stage (two to eight weeks), the ectoderm, the
mesoderm, and the endoderm begin to grow and specialize.
The fetal stage (eight weeks to birth) is characterized
by a rapid increase in complexity and differentiation of the
organs. The fetus becomes active, and most of its systems
become operational.
Describe some of the physical and ethical
challenges that relate to pregnancy.
Some couples need medical aid to help them conceive.
Among the alternate routes to conception are artificial
insemination
and in vitro fertilization (IVF). Some women
may also experience miscarriage or opt for an abortion.
Describe the threats to the fetal environment
and what can be done about them
A teratogen is an environmental agent such as a drug,
chemical, virus, or other factor that produces a birth
defect.
Factors in the mother that may affect the unborn
child include diet, age, illnesses, and drug, alcohol, and
tobacco use. The behaviors of fathers and others in the
environment
may also affect the health and development
of the unborn child.
