Chapter 2 Flashcards
Conception, Pregnancy, and Childbirth.
Assisted Reproductive Technologies (ART)
A range of techniques to help women who are infertile to conceive and give birth.
Chromosomes
Threadlike structures composed of DNA and proteins that carry genes and that are found within each body cell nucleus.
Dominant Genes
Genes that express themselves if present on one or both chromosomes in a pair.
Embryo
The stage of prenatal development beginning in the 2nd week and lasting through the 8th week.
Extremely Low Birth Weight (ELBW)
A newborn weight of less than 1,000 grams (2.2 lbs).
Family Pluralism
Recognition of many viable types of family structures.
Fertilization
The penetration of an ovum by spermatozoon, usually occurring in the fallopian tube.
Fetal Viability
The capability to survive outside the womb, typically requiring at least 25 weeks.
Fetus
The developing organism from the 9th week of pregnancy to birth.
Genes
Basic units of heredity, made of DNA and found on chromosomes.
Genetic Liability
The state of being prone to hereditary disorders.
Genotype
The totality of the hereditary information present in an organism.
Germ Cell
The ova and spermatozoa whose function is to reproduce the organism.
Gestation
The length of maturation time from conception to birth. IN humasn it averages 280 days, with a range of 259 to 287 days.
Gestational Age
The number of completed weeks of pregnancy counting from the first day of the last normal menstrual cycle to the birth of the neonate.
Infertility
The inability to create viable embreyo.
Interactive Genes
Corresponding genes that give seperate yet controlling messages.
Late Preterm Birth
Virth that occurs at 34 to 36 weeks’ gestation.
Low Birth Weight (LBW)
A newborn weight of less than 2,500 grams (5lbs, 8oz).
Miscarriage
Naturally occurring loss of a fetus prior to 20 weeks’ gestation; also known as spontaneous abortion.
Neonate
Infant up to 1 month of age.
Phenotype
The expression of genetic traits in an individual. How it looks.
Recessive Genes
Genes that express themselves only if present on both chormosomes in a pair.
Sensitive Period
A time in fetal development that is particularly sensitive to exposure to teratogens. Different organs have different sensitive periods. Also called critical period.
Sex Chromosomes
Chromosome pair number 23, which determins the sex of the individual.
Sex-linked Trait
A trait that is controlled by a gene located on one of the sex chromosomes.
Small for Gestational Age (SGA)
Lower than normal birth weight, given the number of weeks of gestation.
Spontaneous Abortion
Naturally occurring losss of a fetus prior to 20 weeks’ gestation; also known as miscarriage.
Teratogens
Substances present during prenatal life that adversely affect normal cellular development in form or function in the embryo or fetus.
Very Low Birth Weight (VLBW)
A newborn weight of less than 1,500 grams (3 lbs, 3 oz).
Zygote
A fertilized ovum cell.
