Pregnancy!

But first, a tale of texting to the wrong number, courtesy of Tumblr...

A Few Terms: Zygote: The cell formed by the union of a male sex cell (a sperm) and a female sex cell (an ovum). The zygote develops into the embryo Trimester: A period of three months (usually used to describe periods of time during a pregnancy, but not always Placenta: a flattened circular organ in the uterus of pregnant mammals which nourishes the fetus through the umbilical cord. (It is attached to the umbilical cord.)

Last Time on Awkward Talks with Mr. McIlvaney... Sperm travel from vagina to fallopian tube Sperm try to penetrate egg’s coating Sperm + egg fuse (sperm’s nucleus enters egg) Gestation = 38 weeks (9 months)

First Trimester (0-3 months) Zygote divides in fallopian tube Implants in the uterus (no menstruation/period if pregnant) Amniotic sac forms (fluid filled) in the uterus Placenta forms Brain/nervous system develop Heart beats, sex organ form Urination may increase from pressure on the bladder Nausea and vomiting common

Second trimester (4-6 months) Fetus grow from 8-30 cm Movement of fetus can be felt Fingers and toes obvious Fetus practices breathing

Third Trimester (7-9 months) fetus increases in weight Organs functioning Fetus has sleeping/walking patterns Reacts to external stimuli Lungs mature

Changes During Pre

Birth - YAY Labour begins Cervix dilates and opens Amniotic sac breaks and fluid is released Cervix widens to 10cm Uterine contractions move baby out (head first)

Baby is BORN! Baby takes first breath, umbilical cord is cut and tied

Stem Cells and Differentiation Differentiation: process of growing from unspecialized cells into many different specialized cells

Zygote divides into about 150 unspecialized cells This ball has stem cells

Stem Cells: unspecialized cells that have the ability to reproduce themselves

TWINS! There are two types: Identical and fraternal twins

Fraternal twins Occur when two eggs are released at the same time (usually one from each ovary) Both eggs are fertilized by different sperm and develop in own placenta They have different genetic material

Identical Twins Result of one fertilized egg that splits at the zygote or early embryo stage Each daughter cell develops into an embryo Identical twins are the same gender and have identical DNA