PART 3. FORMING A NEW LIFE Flashcards
time period when conception is possible
fertile window
also known as conception; when ovum and sperm combine to make a zygote
fertilization
a one-celled organism that is formed through fertilization
zygote
once every 28 days; characterized by the rupture of a mature follicle in either ovary and expulsion of its ovum
ovulation
result of 2 separate eggs being fertilized by 2 different sperm to form 2 unique individuals
dizygotic twins or fraternal twins
result from cleaving of one fertilized egg and are generally identical
monozygotic twins or identical twins
genetic transmission of heritable characteristics from parents to offspring
heredity
chemical that carries inherited instructions for the development of all cellular forms of life
deoxyribonucleic acid (DNA)
4 main nucleobases of DNA and RNA
Guanine
Cytosine
Adenine
Thymine
If RNA, adenine bonds with?
Uracil
True or False. A child’s sex is determined by a father’s sperm.
True
Sequence of bases within the DNA molecule which governs the formation of proteins that determine the structure and functioning of living cells.
genetic code
coils of DNA that consists of genes
chromosomes
smallest unit of heredity
genes
complete sequence of genes in the human body
human genome
permanent alterations in genes or chromosomes that may produce harmful characteristics
mutation
chromosomes that are not related to sexual expression
autosomes
it is the 23rd pair that governs the baby’s sex
sex chromosome
the gene for maleness
SRY gene
alternative forms of a gene that occupy the same position on paired chromosomes and affect the same trait
alleles
2 identical alleles for a trait
homozygous
2 different alleles for a trait
heterozygous
when a child receives different alleles, only the dominant one is shown
dominant inheritance
when a child receives identical pair of recessive alleles
recessive inheritance
multiple genes at different sites on chromosomes affect a complex trait
polygenic inheritance
observable characteristics
phenotype
genetic makeup of a person, containing both expressed and suppressed characteristics
genotype
combination of genetic and environmental factors to produce certain complex traits
multiple transmission
mechanism that turns genes on or off and determines functions of body cells
epigenesis
child receives 2 different alleles, resulting in partial expression of a trait
incomplete dominance
certain traits on the X chromosome inherited from the mother are transmitted differently to her male/female offspring
sex-linked characteristics
A birth defect that is characterized by enzyme deficiency that can lead to cirrhois of the liver in early infancy and emphysema and degenerative lung disease in middle age
Alpha, antitrypsin deficiency
Severe anemia that reduces ability of the blood to carry oxygen.
Alpha thalassemia
Severe anemia resulting in weakness, fatigue, and frequent illness.
Beta thalassemia (Cooley’s anemia)
Overproduction of mucus which collects in the lung and digestive tract.
Cystic fibrosis
Usually in males, marked by muscle weakness; minor mental retardation, respiratory failure, and death
Ducheme muscular dystrophy
Excessive bleeding usually in males; in its severe form can lead to crippling arthritis in adulthood.
Hemophilia
Absence of brain tissues
Anencephaly
Incompletely closed spinal canal, resulting in muscle weakness or paralysis and loss of bladder and bowel control; often accompanied by hydrocephalus.
Spina bifida
Metabolic disorder resulting in mental retardation
Phenylketonuria (PKU)
Infantile form: enlarged kidneys, leading to respiratory problems and congestive heart failure
Adult form: kidney pain, stones, hypertension resulting in chronic kidney failure
Polycystic kidney disease
Deformed, fragile RBC that clogs blood vessels, depriving the body of oxygen
Sickle-cell anemia
Degenerative disease of the brain and nerve cells resulting in death bero 5 yrs old.
Tay-sachs disease
SEX CHROMOSOME ABNORMALITIES
XYY XXX (triple X) XXY (Klinefelter) XO (Turner) Fragile X
A sex chromosome abnormality that is indicated by:
MALE
-tall stature
-tendency to have low IQ, especially verbal
XYY
A sex chromosome abnormality that is indicated by: FEMALE -normal appearance -menstrual irregularities -learning disorders -mental retardation
XXX (triple X)
A sex chromosome abnormality that is indicated by: FEMALE -short stature -webbed neck -impaired spatial intelligence -no menstruation -infertility -underdeveloped sex organs -incomplete development of secondary sex characteristics
XO (Turner)
A sex chromosome abnormality that is indicated by:
MALE
-sterility
-underdeveloped secondary sex characteristics
-learning disorders
-small testes
XXY (Klinefelter)
A sex chromosome abnormality that is indicated by:
- minor-to-severe mental retardation
- delayed speech and motor development
- speech impairments
- hyperactivity
Fragile X
Most common chromosomal abnormality; moderate-to-severe mental retardation and by such physical signs as a downward sloping skinfold at the inner corners of the eye. Also known as trisomy-21.
Down syndrome
Clinical service that advises prospective parents of their probable risk of having children with hereditary defects.
Genetic counseling
photograph that shows a chromosome when they are separated and aligned for cell division
karyotype
quantitative study of relative hereditary and environmental influences on behavior
Behavioral genetics
statistical estimate of contribution of heredity to individual differences in a specific trait within a given population
heretability
describes tendency of twins to share the same trait or disorder
concordant
potential variability depending on environmental conditions in the expression of a hereditary trait
reaction range
illustrates how heredity restricts the range of development for some traits
canalization
portion of phenotypic variation that results from the reactions of genetically different individuals to similar environmental conditions
Genotype-Environment Interaction
tendency of certain genetic and environmental influences to reinforce each other
Genotype-Environment Correlation
3 Ways of Genotype-Environment Correlation
Passive Correlations
Reactive (evocative) Correlations
Active Correlations
Note: passive and reactive correlations are common among younger kids
parents’ who provide genes that predispose a child toward a trait, tend to provide an environment that encourages the development of such trait
Passive Correlations
As we grow older, we tend to actively select or create experiences consistent with our genetic tendencies.
Active Correlations
our tendency to seek environments compatible with our genotype
niche-picking
unique environment in which each child grows up, consisting of distinctive influences or influences that affect one child differently than another
non-shared environment
extreme overweight in relation to age, sex, height, and body type
obesity
characteristic disposition or style of approaching and reacting to situations
temperament
mental disorder marked by loss of contact with reality
schizophrenia
the process from conception to birth
gestation
age of an unborn baby, usually dated from the first day of an expectant mother’s menstrual cycle
gestational age
Stages of Prenatal Development
Germinal Stage (Fertilization to 2 Weeks) Embryonic Stage (2 to 8 Weeks) Fetal Stage (8 Weeks to Birth)
A stage in prenatal development marked by rapid cell division, blastocyst formation and implantation in the wall of uterus.
Germinal Stage (Fertilization to 2 Weeks)
A stage in prenatal development marked by rapid growth and development of major body systems and organs.
Embryonic Stage (2 to 8 Weeks)
The process of growth and development of major body systems and organs.
organogenesis
miscarriage; natural expulsion from uterus of an embryo that cannot survive outside the womb
spontaneous abortion
formed from the outer cells that provides oxygen and nutrients to the growing baby in the womb
placenta
formed from the inner cells and is the early stage of development of a multicellular organism
embryo
This germ layer gives rise to the skin and nervous system.
Ectoderm
This germ layer gives rise to the digestive and respiratory system.
Endoderm
This germ layer gives rise to the muscle and skeletal system.
Mesoderm
A stage in prenatal development marked by increased differentiation of body parts and greatly enlarged bodysize.
Fetal Stage (8 Weeks to Birth)
environmental agent that can interfere with normal prenatal development and cause developmental abnormalities
teratogen
mental, motor, and development abnormalities of offspring due to women drinking heavily while pregnant
Fetal alcohol syndrome (FAS)
disease that undermines effective functioning of immune system
Acquired Immunodeficiency Syndrome (AIDS)
physical or psychological demand on a person or organism
stress
PRENATAL ASSESSMENT TECHNIQUES
- Ultrasound (sonogram), sonoembryology
- Embryoscopy, fetoscopy
- Amniocentesis
- Chorionic villus sampling (CVS)
- Preimplantation genetic diagnosis
- Umbilical cord sampling (cordocentesis/fetal blood sampling
- Maternal blood test
uses high frequency sound waves to detect fetus outline and its movements
Ultrasound (sonogram), sonoembryology
Tiny viewing scope inserted in woman’s abdomen to view embryo.
Assists diagnosis of nonchromosomal genetic disorders
Embryoscopy, fetoscopy
Sample of amniotic fluid is withdrawn under guidance of ultrasound and analyzed.
Amniocentesis
Tissues from hair-like chorionic villi (projections of membrane surrounding fetus) are removed from placenta and analyzed.
Chorionic villus sampling (CVS)
After in vitro fertilization, a sample cell is removed from blastocyst and analyzed.
Preimplantation genetic diagnosis
Needle guided by ultrasound is inserted to blood vessels of umbilical cord.
Umbilical cord sampling (cordocentesis/fetal blood sampling
Sample of prospective mother’s blood is tested for alpha fetoprotein.
Maternal blood test
Children with differing genetic makeups evoke different reactions from others.
Reactive (evocative) Correlations
