In this cut -away view you can see both the woman’s and the man’s reproductive organs during intercourse. Here are the penis, vagina, uterus, testicle and prostate gland.
During sexual intercourse, the sperm are released into the vagina near the cervix, which is the entrance to the uterus. Here you can see the sperm swimming through the uterus and up the fallopian tubes. From their profiles, you can see the sperm actually have 3 parts: a head, a middle section, and a tail, which propels them through the uterus.
If you take a closer look at the sperm's head, you’ll see that its covered with an enzyme "cap" that will help it break through the outer wall of the egg cell.
Also within the head are clumps of chromosomes. Chromosomes contain the genetic material, or genes, that are the hereditary blueprints that get passed on to the baby. If a sperm containing a Y chromosome fertilizes the egg, the baby will be a boy. If the lucky sperm contains an X Chromosome, then the baby will be a girl. In addition to a baby’s sex, the genes on the chromosomes determine thousands of other characteristics, including height, body shape, facial features and eye color, and may even influence characteristics like talent and aptitude.
Now let's see what's going on with the egg cell.
Here's the egg cell, moving through the fallopian tube. It can't swim by itself, so it gets moved along by the beating motion of tiny cilia that line the walls of the tube. Unless it gets fertilized, an egg can only survive for 12-24 hours after ovulation. Here you see the egg being met by the sperm. All of the sperm are trying to penetrate the egg.
Actually those sperm are the only remaining survivors of the millions of sperm that were released into the woman’s reproductive tract. The woman’s reproductive tract has an acidic lining and a host of cellular defense mechanisms, making it a hostile environment, and few sperm are strong enough to make it to the egg.
If you watch now you can see the process of fertilization beginning. When one of the sperm cells finally succeeds in breaking through the egg cell's outer membrane, you’ll see something remarkable happen. There it is! The egg cell is locking out other sperm cells from entering. This ensures that only one sperm cell fertilizes the egg cell. If more than one sperm cell was involved, the egg cell might not survive because it would have the wrong amount of genetic material.
Now, here's the final part of fertilization: the sperm cell releases its nucleus containing the father’s chromosomes and then after several hours it unites with the nucleus of the egg cell, which contains the mother’s chromosomes. And when the two nuclei fuse, their genetic material combines together to create a zygote, which is what a fertilized egg cell is called.
Review Date: 4/19/2022
Reviewed By: John D. Jacobson, MD, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Cell division
1:42
Cesarean section
3:47
Conception - general
1:46
Conception - pregnancy
3:20
Conception of identical twins
0:33
Early labor
0:52
Egg cell production
3:54
Egg production
4:02
Fetal ear development
1:13
Formation of twins
3:44
Human face formation
1:57
Intracytoplasmic sperm injection
0:49
Kids - How big is the baby?
1:15
Kids - How does the baby co...
0:42
Kids - Is it a girl or boy?
1:14
Kids - Umbilical cord
1:19
Kids - Where do babies come...
0:50
Ovulation
0:38
Placenta delivery
0:57
Placenta formation
Preeclampsia
0:18
Pregnancy
1:26
Sperm production
2:28
Sperm release pathway
1:53
The role of amniotic fluid
1:45
Twin-to-twin transfusion sy...
1:11
Ultrasound
2:55
Vaginal delivery
0:53
Vasectomy
0:32
Breast engorgement
2:48
C-section
2:14
Endometriosis
2:38
Hysterectomy
2:24
Infant formulas
2:37
Newborn jaundice
2:16
NICU consultants and suppor...
3:13
Pregnancy care
3:18
Storing breast milk
2:07
24-week fetus
Abnormal discharge from the...
Abnormal menstrual periods
Absence of menstruation (am...
Amniocentesis
Amniotic fluid
Anatomy of a normal placenta
Antibodies
Baby burping position
Bananas and nausea
Before and after vasectomy
Birth control methods
Blood cells
Blood test
Breast infection
Breastfeeding
Bulging fontanelles
Candida - fluorescent stain
Caput succedaneum
Childbirth
Chorionic villus sampling
Congenital hip dislocation
Congenital toxoplasmosis
Crying - excessive (0 to 6 ...
Delivery presentations
Developmental milestones
Early weeks of pregnancy
Ectopic pregnancy
Emergency Childbirth
Endocrine glands
Endometritis
Erythroblastosis fetalis - ...
Female breast
Female reproductive anatomy
Female reproductive anatomy...
Female urinary tract
Fetal blood testing
Fetal head molding
Fetus at 10 weeks
Fetus at 12 weeks
Fetus at 16 weeks
Fetus at 26 to 30 weeks
Fetus at 3.5 weeks
Fetus at 30 to 32 weeks
Fetus at 7.5 weeks
Fetus at 8.5 weeks
First trimester of pregnancy
Folic acid
Folic acid benefits
Folic acid source
Follicle development
Fontanelles
Foreskin
Genetic counseling and pren...
Gestational ages
Gestational diabetes
Gonadotropins
Head circumference
Heat rash
Height/weight chart
Hormonal effects in newborns
Hormone-based contraceptives
Humidifiers and health
Infant blood sample
Infant care following delivery
Infant diaphragmatic hernia
Infant heat rash
Infant intestines
Infant jaundice
Infantile reflexes
Influenza vaccines
Intraductal papilloma
Intrauterine device
Intrauterine transfusion
Jaundiced infant
Large fontanelles
Large fontanelles (lateral view)
Macrosomia
Male reproductive anatomy
Male urinary tract
Mammary gland
Meconium
Morning sickness
Moro reflex
Newborn head molding
Newborn test
Normal female breast anatomy
Normal uterine anatomy (cut...
Ovarian cyst
Ovarian hypofunction
Overproductive ovaries
Pelvic adhesions
Pelvic laparoscopy
Placenta
Placenta previa
Polyhydramnios
Pregnancy test
Primary amenorrhea
Primary infertility
Secondary amenorrhea
Secondary infection
Side sectional view of fema...
Single palmar crease
Skull of a newborn
Slit-lamp exam
Sperm
Stein-Leventhal syndrome
Sunken fontanelles (superio...
The cervical cap
The diaphragm
The female condom
The male condom
Tobacco health risks
Transvaginal ultrasound
Tubal ligation
Ultrasound in pregnancy
Ultrasound, color - normal ...
Ultrasound, normal fetus - ...
Ultrasound, normal fetus - face
Ultrasound, normal fetus - foot
Ultrasound, normal placenta...
Ultrasound, normal relaxed ...
Umbilical cord healing
Uterus
Vaginal bleeding during pre...
Vaginal ring
Well baby visits
Yeast infections
CPR - infant - series
Exchange transfusion - series
Rh incompatibility - series