Bio 3201 Continuity of Human Life

Testes (Gonads)

Male reproductive organ that produces sperm.

Scrotum

Pouch that contains the testes

Seminiferous tubule

Tube in testes where sperm are produced.

Interstitial cells

Cells in the testes where sperm are produced.

Epididymis

Duct where sperm mature and become motile.

Vas (ductus) deferens

Storage duct leading to the penis.

penis

Male organ for sexual intercourse

Urethra (male)

The tube through which urine and semen exit the body.

Seminal vesicle

Gland that secretes mucus containing the sugar fructose which is an energy source for sperm.

Prostate gland

Secretes alkaline fluid into the urethra. milky fluid that increases the pH in the female reproductive tract, providing an environment best suited for sperm.

Cowpers gland

Secretes mucus-like fluid into the urethra. Clear mucus fluid that aids in lubrication and neutralizes the acidity of any urine in the urethra.

Ovaries (gonads)

One of a pair of female reproductive organs.

Follicle

Structure in the ovary that contains an ovum.

Fimbriae

Projections that sweep ova from the ovary to the oviduct.

Oviduct (fallopian tube)

Cilia-lined tube that transports ova from the ovary to the uterus.

Uterus

Organ in which an embryo develops before birth.

Endometrium

Membrane that lines the uterus; provides nutrients to the fetus

Cervix

Opening of the uterus; toward the vagina

Vagina

Tube that leads from the exterior to the uterus.

AIDS

There is no cure, treatments are available to manage the infection by lowering the level of virus, to reduce the spread of the virus in the body, and to treat diseases and infections that are associated with having it.

Hepatitis

A vaccine is available. most adults who are infected will clear the virus naturally without treatment. Those who do not clear the virus can develop an acute form of the infection, for which there is no specific treatment.

Genital Herpes

There is no cure or vaccine; once someone is infected the individual carries the virus for life. Antiviral medications can help control and diminish the severity of outbreaks.

HPV

There is no treatment for the virus itself, but treatments exist for health problems the virus can cause. Vaccines are available; however, they do not protect against all cancer-causing types of the virus.

Infertile

A condition when a man or woman has been unsuccessful for over a year at trying to conceive a child- also failure or inability for a woman to carry a child to term.

Sterile

A condition in which a man or woman is unable to have children.

Blocked Oviducts

A type of female infertility. Often an effect of STIs.

Faliure to ovulate

A type of female infertility. caused by hormonal imbalances that occur for a variety of reasons, including being malnourished.

Endometriosis

A type of female infertility. A painful condition in which endometrial tissues grow outside the uterus.

Damaged eggs

A type of female infertility which may be caused by environmental factors such as exposure to toxic chemicals or radiation.

Obstruction

A type of male infertility in the ductus deferens or epididymis, which may be caused by complications arising from STIs or from other blockages in the testicles.

Low sperm count

A type of male infertility caused by numerous factors including overheated testicles, smoking, and alcohol intake.

High proportion of non-viable sperm

A type of male infertility caused by factors including overheated testicles, exposure to toxic chemicals or radiation, and infections such as STIs.

Erectile dysfunction

A male type of infertility caused by factors including vascular disease, nervous system injury, stress, hormonal imbalance, medication, smoking, and alcohol intake.

Artificial insemination

Sperm are collected and concentrated before being placed in the womans vagina. In Some cases, the sperm are donated by the woman’s male partner. In other cases sperm banks are a source of sperm.

In vitro fertilization (IVF)

Offers a solution for women with blocked oviducts. ultrasound machines are used to identify specific follicles that are close to ovulation, stimulation of the ovaries brings a womans eggs to maturity and these eggs can be retrieved directly from these follicles.

In vitro maturation (IVM)

Involves retrieving immature eggs that are treated in the lab, avoiding risks associated with stimulating ovaries.

Gamete intrafallopian transfer (GIFT)

The eggs and sperm are brought together in the oviduct rather than in vitro. This procedure has a higher success rate than IVF

Surrogacy

Sometimes, an infertile couple contracts another woman to carry a baby for them. The woman who carries the baby is called the surrogate mother.

Superovulation

The production of multiple eggs as a result of hormone treatment.

Cyropreservation

The process of freezing eggs, sperm or embryos to sub-zero temperatures for later use.

Gonadotropin Releasing Hormone (GnRH)

Produced in the Hypothalamus. Targets Anterior Pituitary. In male reproductive system: stimulated the release of FSH and LH from the anterior pituitary. In the female reproductive system: Stimulates the development of the sex organs and gamete production.

Lutenizing hormone (LH)

Produced in the anterior pituitary. Targets the ovaries and testes. In the male reproductive system: Stimulates the production of testosterone. In female reproductive system: Triggers ovulation and (with FSH) stimulates estrogen production.

Testosterone

Produced in the testes. Targets the whole body. In the male reproductive system: stimulates the development of the male reproductive tract and secondary sex characteristics. In the female reproductive system: combined with estrogen (the female sex hormone) testosterone helps with the growth, maintenance, and repair of a womans reproductive tissues, bone mass, and human behaviors.

Inhibin

Produced in the testes. Targets anterior pituitary and hypothalamus. In the male reproductive system: inhibits FSH production. In the female reproductive system: Inhibits FSH production.

Estrogen

Produced in the ovary. targets the uterus. In the male reproductive system: inhibits FSH production. In the female reproductive system: causes uterine thickening.

Progesterone

produced in the ovary. Targets uterus. In male reproductive system: Very little produced to help in production of testosterone. In female reproductive system: Causes uterine thickeneing.

Menstual Cycle

20-45 day cycle in which hormones stimulate development of the uterine lining and an ovum is released.

Ovarian cycle

When one follicle matures, releases and voum, and then develops into a yellowish, gland-like structure known as a corpus luteum.

Follicular Stage

The first stage. Begins with an increase in the level of FSH released by the anterior pituitary gland.

Ovulation

Marks the end of the follicular stage and the beginning of the second stage.

Luteal Stage

Second stage. Once the ovum has been released, LH causes the follicle to develop into a corpus luteum.

Fertilization

Joining of a male and a female gamete.

Zygote

Cell formed by the union of two gametes.

Cleavage

Process of cell division without growth.

Morula

Is an early-stage embryo consisting of 16 cells (called a blastomeres) in a solid ball.

Blastocyst

Embryo at the stage of implantation; consists of the trophoblast and inner cell mass.

Trophoblast

Forms the outer layer of the blastocyst.

Implantation

Attachment of the blastocyst to the endometrium.

Human Chorionic Gonadotrophin (hCG)

Hormone secreted by the trophoblast during implantation.

Gastrulation

Formation of the three primary germ layers.

Ectoderm

Outer layer in embryonic disk which is closer to the amniotic cavity.

Endoderm

An inner layer of the embryonic disk.

Mesoderm

Forms between the endoderm and ectoderm.

Morphogenesis

The series of events that forms distinct structures of the developing organism. Depends on the ability of early embryonic cells to become different types of cells.

Differentiation

Process that allows specialization.

Neurulation

Process of forming the neural tube.

Neurula

Is a vertebrate embryo at the early stage of development in which neurulation occurs.

Extra-embryonic membranes

System of membranes external to the embryo for protection, nutrition, respiration, and excretion.

Chorion

The outermost membrane. It encloses all the other extra-embryonic membranes, as well as the embryo. The chorion forms the fetal portion of the placenta.

Amnion

A transparent sac that develops from cells of the embryonic disk. It grows to enclose the embryo completely. It is penetrated only by the umbilical cord.

Amniotic fluid

A fluid that protects the embryo from trauma and temperature fluctuations, allows freedom of movement, and prevents limbs from sticking to the body.

Allantois

Forms the foundation for the umbilical cord. During the second month the allantois degenterates.

Yolk sac

A small sac that is suspended from the abdominal area of the embryo. It contributes to the formation of the digestive tract and produces the first blood cells and the future egg or sperm cells.

Placenta

A disk-shaped organ that is rich in blood vessels. The embryo (or fetus) is attached to the uterine wall by the placenta, and metabolic exchange occurs through it.

Embryo

Early stage of development of a multicellular organism. Usually 1-8 weeks.

Oraganogenesis

The process by which the three germ tissue layers of the embryo, which are the ectoderm, endoderm, and mesoderm, develop into the internal organs of the organism.

Partuition

The process of giving birth.

Dialation Stage

Stage uterine contactions and oxytocin cause the cervix to open, or dialate.

Expulsion Stage

Forceful contractions push the baby through the cervix to the birth canal.

Placental stage

About 10 to 15 minutes after the baby is born, the placenta and umbilical cord are expelled from the uterus.

Positive feedback loop

Mechanism that can explain the onset and continuation of labour.

Lactation

The formation and secretion of breast milk.

Teratogen

Any agent that causes a structural abnormality due to exposure during pregnancy.

Home Pregnancy Tests

A type of pregnancy test where the urine contains enough hCG for this type of pregnancy test.

Ultrasound

A type of pregnancy test that uses waves sent through the body to provide information about internal structures, such as a developing fetus.

Fetoscopy

A type of pregnancy test, an endoscopic procedure during pregnancy to allow surgical access to the fetus, the amniotic cavity, the umbilical cord, and the fetal side of the placenta.

Amniocentesis

A type of pregnancy test invloving the withdrawl of a sample of amniotic fluid from the uterus after the 14th weeks due to risk of injuring the fetus.

Chronic Villi Sampling (CVS)

A type of pregnancy test involving the removal of fetal cells from the chorion of rgenetic testing.

Maternal blood tests

A type of pregnancy test that does not require sampling of fetal cells but rather blood cells.

Stem cells

Special human cells that are able to develop into many different cell types.

Multipotent cells

Cells that can develop into more than one cell type, but are more limited than pluripotent cells.

Embryonic Stem Cells

These cells come form embryos that are three to five days old. At this stage, an embryo is called a blastocyst and has about 150 cells.