chapter 19 lesson one pgs 486-491 the beginning of the life cycle
TRANSCRIPT
FertilizationThe union of a male sperm cell and female egg cell is called fertilization or conception
ImplantationThe zygote has divided many times to form a cluster of cells
The zygote (fertilized egg) travels through the fallopian tube
The zygote attaches to the uterine wall (implantation)
Stages of Fetal Development
First Trimester (0-14 weeks)
Spinal cord growsBrain, ears, and
arms begin formingHeart begins to
beat12 week fetus
Stages of Fetal Development
Second Trimester (15-28 weeks)
Fetus body growsMother can feel
fetal movementEyebrows and
eyelashes developFetus can hear
20 week fetus
Stages of Fetal Development
Third Trimester (29-40 weeks)
Fetus uses all five senses
Fetus gains weightFetus becoming
crowded in uterusLungs fully develop
36 week fetus
Stages of BirthIn final weeks,
mother experiences weak contractions
Contractions become regular and stronger
The cervix dilates, preparing for the baby to exit
Labor is the final stage, the uterus contracts and pushes the baby out