Chapter 2: From Conception to Birth

Question 1

Definition of Human Development

Answer 1

how and why people - all kinds of people, everywhere, of every age - change

Question 2

Chromosomes

Answer 2

Molecules of DNA. DNA consists of 46 chromosomes arranged in 23 pairs.
males have XY and females have XX

Question 3

Chromosome Abnormalities

Answer 3

about once in every 200 births, an infant is born with 45, 47, 48, or even 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

Question 4

Dominant Genes

Answer 4

more influential than recessive gene (non-additive), can completely control the phenotype with no noticeable effect of recessive gene.
genes for blood type B and Rh-positive blood are dominant

Question 5

Recessive Genes

Answer 5

less influential than dominant genes and are usually not expressed, sometimes they can be noticed, such as a dominant brown eye and recessive blue eye gene can result in hazel eyes

Question 6

Heretibility

Answer 6

Statistical term that indicates what portion of the variation in a particular
trait within a particular
population is inherited.
environment can affect the expression of inherited genes

Question 7

Genotype

Answer 7

An organism’s genetic inheritance, or genetic potential. Unique for each organism

Question 8

Phenotype

Answer 8

The observable characteristics of an organism, including appearance, personality, intelligence, and all other traits

Question 9

Zygote

Answer 9

Two gametes (sperm and ovum) combine and produce a new individual with 23 chromosomes from each parent

Question 10

Embryo

Answer 10

3rd through 8th week after conception.
Primitive streak appears down middle of cell mass.
Head takes shape, eyes, ears, nose, mouth, form.
heart starts pulsating
webbed fingers and toes separate.

Question 11

Fetus

Answer 11

week 9 after conception to birth.
genitals form end of 3rd month and sex hormones cause the difference of fetal brain organization.
weighs 3 ounces at 3 months.
Heartbeat detectable through stethoscope.
period of greatest brain growth at 4th, 5th, and 6th months.
prefrontal loves bot fully mature.
brain is far bigger than any other body part at birth

Question 12

Monozygotic (Identical) Twins

Answer 12

originate from one zygote that splits apart early in development.
an incomplete split results in conjoined twins.
same genotype but slight variations in phenotype are possible due to environmental influences

Question 13

Dizygotic (Fraternal) Twins

Answer 13

result from two separate ova by two separate sperm.
dizygotic twins have half of their genes in common and occur twice as often as monozygotic twins.
incidence is genetic and varies by ethnicity and age

Question 14

Apgar Score

Answer 14

A quick assessment of babies heart rate, breathing, muscle tone, color, and reflexes.
completed twice (1 to 5 minutes after birth.
score of 0, 1 or 2 in each category.
desired score is 7 or above

Question 15

Age of Viability

Answer 15

Age at which a preterm newborn may survive outside the mothers uterus if medical care is available.
about 22 weeks after conception.

Question 16

Normal Birth

Answer 16

fetal brain signals the release of hormones to trigger the females uterine muscles, labor begins, the average duration for first born babies being 12 hours, quicker for later born babies

Question 17

Medical Interventions

Answer 17

cesarean section (c-section), a surgical birth, fetus can be removed quickly, and usually safe for mother and baby, having lives when the fetal head is too large for the pelvis

Question 18

Traditional and modern birthing practices

Answer 18

home births, hospital births, and a doula

Question 19

Doula

Answer 19

a woman who helps with labor, delivery, breast feeding, and newborn care.
may also be related to lower rate of c-sections

Question 20

Postpartum Depression

Answer 20

sadness and inadequacy felt by 8-15% of new mothers in the days and weeks after giving birth.
symptoms range from baby blues to postpartum psychosis.
depressed mothers find baby care burdensome and may think about mistreating the infant,
prenatal involvement can have beneficial effects.
some fathers are depressed themselves.
causes for postpartum depression vary

Question 21

Teratogens

Answer 21

any agent condition, including viruses and drugs, resulting in birth defects or complications

Question 22

Behavioral Teratogens

Answer 22

agents and conditions that can harm, the prenatal brain, impairing the future child’s intellectual and emotional functioning

Question 23

Birth Defects

Answer 23

these occur from exposure to mass amounts of teratogens causing several defects to the fetus, one of them being fetal alcohol syndrome (FAS), which causes abnormal facial characteristics, slow physical growth, and retarded mental development

Question 24

Germinal Period

Answer 24

the first two weeks of conception.
consists of rapid cell division and beginning of cell differentiation.
duplication and division within hour of conception.
development of placenta, as organ that surrounds developing embryo is attached to the wall of the uterus, and sustains life via the umbilical cord (nourishes and carries waste)

Question 25

Embryonic Period

Answer 25

the 3rd through the 8th week.
basic forms of all body structures develop.
begins when primitive streak appears down the middle of the cell mass.
primitive streak becomes the neural tube and later forms the brain and spine. head takes shape, eyes, nose, and mouth form, heart begins to pulsate, and extremities develop and webbed fingers and toes separate

Question 26

Fetal Period

Answer 26

the 9th week until birth. fetus grows in size and matures in functioning. genitals form at end of third month and sex hormones cause differences in fetal brain organization.
weighs about 3 ounces at s months.
heartbeat detectable through stethoscope.
All body parts and systems complete rental development.
Experience the period of greatest brain growth during the 4th, 5th, and 6th months.
Cortex not fully mature at birth.
Brain at birth is far bigger than any other part of the body.

Question 27

Fertilization

Answer 27

One sperm penetrates the ovum. Nuclei (genetic material) of the male and female cells combine

Question 28

Trimesters

Answer 28

germinal period, embryonic period, and fetal period

Question 29

Kangaroo Care

Answer 29

Child-care technique in which the mother of a low birthweight infant holds the baby between her breasts.
Allows baby to hear mothers heartbeat and feel her body heat

Question 30

Schema

Answer 30

cognitive framework or concept that helps organize and develop and interpret information