Pregnancy occurs from fertilization of an ovum and completes with childbirth. This is the 38-week period of development.

This is when the nuclei of the sperm and egg combine.

This union is a single cell.

This is a ball of identical cells as a result of the zygote dividing rapidly.

This is the morula when it develops into a partially hollow structure.

This is when the blastocyst burrows into a thickened uterine lining and is implanted and completely covered.

A group of cells within the blastocyst called inner cell mass becomes this...

The growing offspring from the beginning of the third month of gestation until birth.

This is a flat circular organ that consists of a spongy network of blood-filled sinuses and capillary-containing villi.

The maternal portion of the internal section of the endometrium.

The embryonic portion of the endometrium.

The embryo is connecting to the placenta by a stalk of tissue.

This section delivers a small amount of oxygen-rich blood to the liver. *But, most of the blood bypasses the liver and is added to the oxygen-poor blood in the inferior vena cava*

Once blood enters the right atrium, most of the blood flows directly into the left atrium through a small opening in the atrial septum.

A small amount of blood goes to the lungs, most of the rest shunts directly into a systemic circuit through this small blood vessel.

Blood travels through most of the fetal tissue and returns to the placenta to pick up oxygen through two.....

Shortly after implantation, the blastocyst produces a hormone called...

This is one of the hormones secreted by the placenta and stimulates growth of breast to prepare for lactation or production of milk.

This is a placental hormone that softens the cervix and relaxes the sacral joints and the pubic symphysis.

The entire gestation period may be divided into three equal sections called...

This surrounds the fetus and serves as a protective cushion.

This clear fluid fills the amniotic sac.

The total period of pregnancy from fertilization of ovum to birth is this long...

This is an ultrasound image.

This instrument converts the reflected sound waves into electrical energy and a computer produces a image on a screen.

Pressure on the cervix from the baby stimulates the release of this hormone. *This hormone stimulates uterine contractions*

This is a type of feedback mechanism is less common. *It intensifies a response until the object of the response is removed*

This is the process of the fetus being expelled from the uterus.

This begins at the onset of regular uterine contractions. When the cervix becomes thinner and cervical canal larger.

This begins when cervix is completely dilated and ends with the baby's birth.

This begins after the child is born and ends with the expulsion of the afterbirth.

This begins after the expulsion of the afterbirth and the period of which bleeding is controlled. *Contraction of the uterine muscles attempt to close off the blood vessels leading to the placenta site*

This is the result from the fertilization of two different ova by two spermatozoa. T

This is the result from a single zygote formed from a single ovum fertilized by a single spermatozoon. *During the stage of development the singe zygote separates into two units and usually share a placenta*

This refers to the loss of the embryo or fetus before the 20th week of pregnancy.

This occurs naturally with no interference and commonly referred to as a miscarriage.

This occurs as a result of deliberate interruption of pregnancy.

This refers to the loss of the fetus after the 20th week of pregnancy.

This refers to the birth of an infant who is lifeless.

These are contained in the female breast and are associated organs of the reproductive system.

This is a mammary gland secretion that is thin liquid.

This is the process of various traits transmitted from parents to offspring.

Genes are segments of DNA contained in theses...

These type of chromosomes are not involved in the determination of sex.

This is each version of a specific gene.

This occurs when both alleles for a trait are the same.

This occurs when both alleles for a trait are different.

This allele expresses effect in the cell regardless of the identity of the other allele.

This allele is not evident unless paired with an allele on the matching chromosome.

A characteristic like eye color is a part of a persons...

This is any trait called on a sex chromosome.

This is the result of two or more gene pairs acting together.

This can result from an induced agent like ionizing radiation or a chemical causing small changes in the gene sequence.