Testes
Male reproductive organ that produces sperm and male hormones.
Sperm
The male sex cells that carry a man's genetic material.
Scrotum
Pouch of skin that contains the testes and helps regulate the temperature of the testes for optimal sperm production.
Seminiferous Tubules
Long, coiled tubes in the testes where sperm are produced.
Interstitial Cells
Hormone secreting cells that release testosterone.
Epididymis
Duct where sperm mature and become motile.
Vas (Ductus) Deferens
Storage duct that is connected to the penis. Sperm cells move out of each epididymis through this.
Penis
Male organ for sexual intercourse, its primary function is to transfer sperm into the female reproductive system.
Seminal Vesicles
Secretes mucus-like fluid that contains sugar as energy source for sperm.
Prostate Gland
Secretes an alkaline fluid that increases the pH in the female reproductive tract, aiding in protection for sperm.
Cowper’s Gland
Secretes a mucus-like fluid that aids in lubrication and neutralizing the acidity of any urine in the urethra.
Semen
The combination of sperm cells and fluid.
Ovaries
Female gonads which produce eggs and female hormones.
Egg (ova)
The female reproductive cell, or gamete that is formed in the female ovary.
Follicles
Structures that develop and mature in the ovaries and are responsible for containing an egg.
Fimbriae
Thread-like projections that sweep the egg from the ovary to the oviduct (fallopian tube).
Fallopian Tubes (Oviducts)
Tube that connects the ovary to the uterus. Is ciliated which helps move the egg towards the uterus.
Uterus
Muscular organ that holds and nourishes a developing fetus.
Endometrium
Vascular membrane that lines the wall of the uterus, it supplies nutrients for the fetus.
Myometrium
The muscular wall of the uterus.
Cervix
Muscular tissue that forms the opening of the uterus to the vagina.
Vagina
Tube that leads from the exterior to the uterus and acts as the entrance for an erect penis to deposit sperm. Additionally, it acts as the birthing canal.
Sexually transmitted infection (STI)
Caused by a bacteria, virus, or parasite that can be passed from one person to another during sex or intimate contact.
Chlamydia
Bacterial STI and is caused by the bacterium Chlamydia trachomatis. Can be treated with antibiotics.
Gonorrhea
Bacterial STI and is caused by the bacterium Neisseria gonorrhoeae. Can be treated with antibiotics.
Hepatitis
Includes three types of viral infections: hepatitis A, B, and C; because hepatitis B is spread through sexual contact it is considered to be an STI. A vaccine for hepatitis B is available.
Herpes
An extremely common STI caused by one of two herpes viruses: herpes simplex 1 (HSV 1) or herpes simplex 2 (HSV 2). HSV 2 is more likely to be acquired through genital contact, causing genital herpes. There is no cure or vaccine.
HIV / AIDS
Caused by a group of related viruses that are collectively called human immunodeficiency virus. It attacks white blood cells. There is no cure.
HPV
A common group of viruses responsible for genital warts. There is no treatment for the virus. Vaccines are available.
Syphilis
An infection caused by the bacterium Treponema pallidum. Proceeds in three stages. Can be treated with antibiotics.
Spermatogenesis
The process by which sperm cell production occurs.
Secondary Sexual Characteristics
A physical characteristic of an organism that is related to or derived from its sex, but not directly part of its reproductive system.
Puberty
The period during which adolescents reach sexual maturity and become capable of reproduction.
Andropause
When the production of testosterone and other male hormones slowly decline.
Gonadotropin Releasing Hormone (GnRH)
Produced by the hypothalamus. Acts on the pituitary gland, causing it to release FSH and LH.
Follicle-Stimulating Hormone (FSH)
Males: Produced by the pituitary gland. Stimulates the testes to begin producing sperm.
Females: Produced by the pituitary gland. Stimulates the ovaries to begin egg production.
Luteinizing Hormone(LH)
Men: Produced by the pituitary gland. Stimulates the testes to release testosterone.
Women: Produced by the pituitary gland. Triggers ovulation and stimulates the production of female sex hormones.
Testosterone
Male sex hormone produced by the testes. Stimulates the male reproductive tract and secondary sex characteristics.
Inhibin
Produced by the testes. Acts on the pituitary gland to inhibit FSH production.
Hypothalamus
Releases hormones that direct other hormones or other glands control our body.
Pituitary Gland
Makes growth hormones which regulate the growth of other hormones.
Oogenesis
The production or development of an ovum (egg).
Menopause
A hard stop to the end of monthly menstruation due to loss of ovarian follicular function. This means that the ovaries stop releasing eggs for fertilization.
Estrogen
Female sex hormone produced by the ovaries. Stimulates the female reproductive tract and secondary sex characteristics.
Progesterone
Female sex hormone produced by the ovaries. It causes uterine wall thickening.
Menstrual Cycle
Hormonal regulation of the female reproductive system.
Ovarian Cycle
Is divided into two stages: the follicular stage and the luteal stage. Begins with an increase of FSH. FSH stimulates a follicle to mature. As the follicle matures, it releases estrogen and progesterone. Increased estrogen levels inhibit the release of FSH. Additionally, increased estrogen levels stimulates a sharp increase in LH which triggers ovulation. Increased LH causes the follicle to develop into a corpus luteum. Corpus luteum secretes progesterone and some estrogen. Increased progesterone and estrogen inhibit FSH and LH production. The corpus luteum will disintegrate, leading to a gradual decrease in progesterone and estrogen. Decrease in progesterone and estrogen causes an increase in FSH, which restarts the cycle.
Uterine Cycle
When a new follicle matures and releases estrogen, the endometrial wall begins thickening. After ovulation, when the corpus luteum produces progesterone, a more rapid thickening occurs. If fertilization does not occur, estrogen and progesterone drop, and the endometrium breaks down
Follicular Stage
Days 1-14. Begins with an increase of FSH. FSH stimulates a follicle to mature. As the follicle matures, it releases estrogen and progesterone. Increased estrogen levels inhibit the release of FSH. Additionally, increased estrogen levels stimulates a sharp increase in LH which triggers ovulation.
Ovulation
The process in which a mature egg is released from the ovary.
Luteal Stage
Days 15-28. Begins after ovulation. Increased LH causes the follicle to develop into a corpus luteum. Corpus luteum secretes progesterone and some estrogen. Increased progesterone and estrogen inhibit FSH and LH production. The corpus luteum will disintegrate, leading to a gradual decrease in progesterone and estrogen. Decrease in progesterone and estrogen causes an increase in FSH, which restarts the cycle.
Corpus Luteum
An increased LH causes the follicle to develop into this.
Menstruation
If fertilization does not occur, estrogen and progesterone drop, and the endometrium breaks down.
Sterility
A condition in which a man or woman is unable to have children.
Infertility
A condition when a man or woman have been unsuccessful for over a year trying to conceive a child.
Artificial Insemination
Sperm are collected and placed in the woman’s vagina.
In Vitro Fertilization
Eggs and Sperm are collected and fertilization is induced outside of the body. The embryo is placed in the uterus.
Surrogacy
Contracting another woman to carry the baby to term.
Superovulation
Hormone treatment that stimulates follicle development and ovulation of multiple eggs.
Cryopreservation
The use of very low temperatures to preserve structurally intact living cells and tissues.
Surgical sterilization
For women: tubal ligation, which involves cutting the oviducts and tying off the cut ends. This ensures that sperm never reaches the uterus. For men: vasectomy, which involves cutting and tying off the ductus deferens. This ensures semen does not contain sperm.
Hormonal Contraception
Several types are available that act by changing the balance of reproductive hormones in women. These include: birth control pill, patch, vaginal ring, (IUD).
IUD
T-shaped device, inserted into the uterus by a doctor, that has a small cylinder with progestin that is slowly released
Spermicides
A chemical that destroys sperm upon contact.
Condoms
The male one covers the penis and the female one is inserted in the vagina.
Abstinence
Complete lack of sexual intercourse.
Rhythm Method
A form of natural family planning. You track your menstrual history to predict when you'll ovulate. This helps you determine when you're most likely to conceive.
Fertilization
The action or process of fertilizing an egg, involving the fusion of male and female gametes to form a zygote.
Zygote
Is the fusion of male sperm and female egg. Resulting single cell.
Cleavage
Following fertilization, the zygote divides rapidly by mitosis. Despite cell division, the zygote doesn’t grow in size. The process of cell division without growth.
Morula
By the time the zygote is a sphere of 16 cells.
Blastocyst
Once the morula enters the uterus, it develops into a hollow ball of cells.
Trophoblast
The outer cellular layer. Develops into the chorion, which develops into the placenta.
Inner Cell Mass
Mass of cells that develops into the embryo itself.
Implantation
Between the fifth and seventh day, the blastocyst embeds itself into the endometrial lining of the uterus.
Human Chorionic Gonadotropin (HCG)
A hormone for the maternal recognition of pregnancy produced by trophoblast cells. The presence of it is detected in some pregnancy tests.
Gastrulation
Is the formation of the three primary germ layers.
Gastrula
An embryo at the stage following the blastula, when it is a hollow cup-shaped structure having three layers of cells.
Germ Layers
The first layer of cells that form during embryonic development. They’re called: Ectoderm, Mesoderm, and Endoderm.
Cell Differentiation
Is the process that allows specialization of cell function.
Morphogenesis
When distinct structures start to form.
Neurulation
At two weeks,this process begins
Notochord
The backbone.
Neutral Tube
The brain and spinal cord.
Allantois
Forms the umbilical cord.
Amnion
Fluid-filled sac used for protection.
Chorion
Forms the placenta.
Yolk Sac
Site of the first blood cell production.
Placenta
Formed from the chorion, it attaches the fetus to the uterine wall. The site of metabolic exchange. Nutrients and oxygen diffuse from the mother’s circulatory system to the baby, and waste products leave the baby’s circulation.
Umbilical Cord
Forms around the end of the eighth week. Connected from the navel of the fetus to the placenta. Is made of two arteries which remove oxygen poor blood, and one vein which transports oxygen rich blood.
Trimester
a period of three months, especially as a division of the duration of pregnancy.
Dizygotic Twins
Or fraternal twins. Two eggs, two sperm
Monozygotic Twins
Or identical twins. One egg, one sperm, one fertilization
Parturition
Is the process of giving birth. There are three stages: Dilation, Expulsion, and Placental.
Dilation Parturition
Uterine contractions cause the cervix to dilate. Amniotic sac breaks, fluid is released.
Expulsion Parturition
The baby is born. It pushes through the cervix to the birth canal.
Placental Parturition
After the birth, the placenta and umbilical cord are expelled from the uterus. The afterbirth.
Oxytocin
Hormone that stimulates uterine contractions.
Lactation
Is the formation and secretion of breast milk.
Prolactin
Is the hormone needed for milk production. Following birth the pituitary begins to produce and secrete prolactin so milk can be produced.