Term
|
Definition
| Two gametes (sperm and ovum) combine and produce a new individual with 23 chromosomes from each parent. |
|
|
Term
|
Definition
-An organism's genetic inheritance, or genetic potential
-Unique for each organism |
|
|
Term
|
Definition
| The observable characteristics of an organism, including appearance, personality, intelligence, and all other traits. |
|
|
Term
|
Definition
-Variation of a gene or any of the possible forms in which a gene for a particular trait can occur.
-Effects of variations vary greatly from causing life-threatening conditions to having no detectable effect at all. |
|
|
Term
|
Definition
-Identical
-Originate from one zygote that splits apart very early in development
-Incomplete split results in conjoined twins.
-Same genotype but slight variations in phenotype are possible due to environmental influences. |
|
|
Term
|
Definition
-Fraternal
-Result from fertilization of two separate ova by two separate sperm.
-Dizygotic twins have half their genes in common and occur twice as often as monozygotic twins.
-Incidence is genetic and varies by ethnicity and age. |
|
|
Term
|
Definition
-Direct the interactions of other genes, controlling their genetic expression, duplication, and transcription
-Are responsible for differences between species |
|
|
Term
| 3 main periods of prenatal development |
|
Definition
1) Germinal Period (first two weeks after conception): rapid cell division and beginning of cell differentiation
2) Embryonic Period (3rd through 8th week): basic forms of all body structures develop
3) Fetal Period (9th week until birth): fetus grows in size and matures in functioning |
|
|
Term
| Germinal period characteristics |
|
Definition
-Development of the placenta
-Implantation (about 10 days after conception)
-Organism grows rapidly |
|
|
Term
| Embryonic period characteristics |
|
Definition
-Primitive streak becomes the neural tube and later forms the brain and spine of the CNS.
-Head takes shape.
-Eyes, ears, nose, and mouth form.
-Heart begins to pulsate.
-Extremities develop and webbed fingers and toes separate. |
|
|
Term
| Fetal period characteristics |
|
Definition
-Genitals form and sex hormones cause differences in fetal brain organization.
-Cephalocaudal and proximodistal growth
-Heartbeat detectable
-All body parts and systems complete prenatal development.
-Cortex is not fully mature at birth.
-Brain at birth is far bigger than any other part of the baby. |
|
|
Term
|
Definition
-Appearance
-Pulse
-Grimace
-Activity
-Respiration |
|
|
Term
|
Definition
-Maintaining oxygen: Breathing, hiccupping, sneezing
-Maintaining constant body temperature: Crying, shivering, tucking legs to body, pushing
-Managing feeding: Sucking, rooting, swallowing |
|
|
Term
|
Definition
-About once in every 200 births, an infant is born with 45, 47, or even 48 or 49 chromosomes which produces syndrome.
-Most common condition is Down syndrome (trisomy-21).
-About 1 in every 500 infants is born with only one sex chromosome (no Y) or with three or more. |
|
|
Term
|
Definition
-Half of the offspring of parents with a dominant disorder will have the disorder.
-Most dominant disorders begin in adulthood (fatal dominant childhood conditions cannot be passed on).
-Many dominant disorders have relatively mild or variable symptoms.
-Tourette syndrome |
|
|
Term
|
Definition
| -Millions of different types, lethal conditions are rare. (ex. Sickle cell, cystic fibrosis). |
|
|
Term
|
Definition
-Prenatal teratogens - any agent or condition, including viruses, drugs, and resulting in birth defects or complications
-Behavioral teratogens - agents and conditions that can harm the prenatal brain, impairing the future child's intellectual and emotional |
|
|
