Human Development - Chapter 3: Practice Test Questions

yolk sac

A ________________ emerges that produces blood cells until the developing liver, spleen, and bone marrow are mature enough to take over this function.

False

As many as 50 percent of zygotes do not survive the first two weeks.

False

At 28 weeks, the fetus is awake about 30 percent of the time.

second trimester

At the end of the _______________, most of the brain's neurons are in place and begin rapidly forming synapses.

False

Brain weight doubles from the twentieth week until birth.

second week

By the end of the _______________, cells of the trophoblast form a protective membrane, the chorion, which surrounds the amnion.

second month

By the end of the ________________, the embryo responds to touch and can move.

second trimester

By the middle of the __________________, the mother can feel the movements of the fetus.

fifth week

During the ______________, production of neurons begins.

True

During the last half of the first month of pregnancy, the nervous system develops fastest.

the fetus

During the period of ___________, from the ninth week to the end of pregnancy, the organism increases rapidly in size.

the embryo

During the period of _________________, from implantation through the eighth week of pregnancy, the groundwork is laid for all body structures and internal organs.

False

During the period of the fetus, the groundwork is laid for all body structures and internal organs.

True

Fertilization usually takes place in the fallopian tube.

embryonic disk

In the last half of the first month, the ___________________ forms three layers of cells—ectoderm, mesoderm, and

True

In the second month of pregnancy, the eyes, ears, nose, jaw, and neck form.

True

Research indicates that more active fetuses during the third trimester become 2-year-olds who are less fearful of unfamiliar adults.

(1) the germinal period, (2) the period of the embryo, and (3) the period of the fetus.

The 38 weeks of pregnancy are usually divided into three periods:

fetus

The ___________ also receives antibodies from the mother's blood that protect against illnesses.

ectoderm

The ____________ folds over to form the neural tube. At 3½ weeks, the top of the neural tube swells to form the brain.

trophoblast

The ________________ forms a membrane, the amnion, that encloses the developing organism in protective amniotic fluid.

third trimester

The _________________ brings greater responsiveness to external stimulation.

germinal period

The _____________________ lasts about two weeks, from fertilization until the cell mass attaches itself to the wall of the uterus.

True

The age of viability occurs sometime between 22 and 26 weeks.

between 22 and 26 weeks

The age of viability, _________________, is the point at which the baby can first survive if born early.

vernix; lanugo

The fetus is covered with a white, cheeselike substance called ________ and with white, downy hair called __________.

True

The period of the fetus is the longest prenatal period.

The placenta

__________________, which brings the embryo's and mother's blood close together, is connected to the developing organism by the umbilical cord.

Prenatal development

___________________ is sometimes divided into three equal time periods called trimesters.

Implantation

____________________ occurs between the seventh and ninth days, when the blastocyst burrows deep into the uterine lining.

Conception

______________________ usually takes place in one of the woman's two fallopian tubes, where sperm and ovum unite to form the zygote.