Unit 2: Start of Life

sperm

male reproductive cell

ovum

female reproductive cel

what does fertilzation create?

zygote

monozygotic twins

genetically identical

dizygotic twins

no more genetically similar than two siblings

karyotype

visual representation of an individual’s complete set of chromosomes

ultrasound

uses sound waves to create images of fetus

amniocentesis

sample of amniotic fluid is tested for genetic abnormalities

chorionic villus sampling (CVS)

placental tissue is tested early in pregnancy for chromosomal abnormalities

germinal stage

0-2 weeks

zygote rapidly divides through cell division

blastocyst

rapidly diving cluster of cells

placenta

organ that provides nutrients and oxygen to developing baby

embryonic stage

embryo (2-8 weeks)

major organs/body systems begin forming

3 germ layers

ectoderm

skin and nervous systems

mesoderm

muscles, bones, and circulatory system

endoderm

lungs and digestive organs

fetal stage

fetus (8/9 weeks-birth)

organs become more functional

growth in size/weight accelerates

teratogen

substance or agent that can cause abnormal development in fetus during pregnancy

artificial insemination

sperm injected into reproductive tract

in vitro fertilization (IVF)

fertilization outside of female body

1st stage of birth

longest

contractions every 8-10 min lasting 30 sec

cervix opens

2nd stage of birth

baby’s head move through birth canal

stage ends when baby is born

3rd stage of birth

occurs when umbilical cord and placenta are expelled

shortest stage

obstetricians

medical doctor who specializes in female reproductive health

midwife

healthcare professional who cares for mothers during normal pregnancies, labor, birth and postpartum period

doula

non-medical professional who provides physical, emotional and mental support to expecting mother and families

stillbirth

occurs when a baby dies in the womb after 20 weeks after pregnancy