Question 1

The fetal period refers to the time of development extending from the end of the ___ month after fertilization until birth.
A)1st
B)2nd
C)3rd
D)4th
E)5th

Accepted Answer

The fetal period begins at the end of the 2nd month after fertilization, when the embryo transitions into the fetal stage of development, continuing until birth.

Question 2

The term neonatal period refers to the first ___ days after birth.
A)40
B)28
C)36
D)12
E)8

Accepted Answer

The neonatal period refers to the first 28 days after birth.

Question 3

Successive cleavages of the zygote produce a solid sphere of small cells called the
A)embryo
B)blastocyst
C)morula
D)gamete
E)trophoblast

Accepted Answer

The morula is formed after the zygote undergoes several rounds of cell division, resulting in a solid sphere of small, undifferentiated cells. The blastocyst, on the other hand, is formed later when a fluid-filled cavity appears within the morula, creating an inner cell mass and an outer layer of trophoblast cells. The embryo refers to the developing organism after the blastocyst stage, and gametes are the haploid cells involved in sexual reproduction.

Question 4

Fraternal twins
A)develop from a single fertilized ovum.
B)are the same age but genetically different.
C)develop from the same zygote.
D)are always the same sex.
E)are fertilized by one sperm cell.

Accepted Answer

Fraternal twins are the result of two separate eggs being fertilized by two different sperm, meaning they can be genetically different and not develop from the same zygote. They can also be different sexes, further illustrating their genetic differences. The fact that they are the same age is simply due to being born at the same time, not because they developed from a single fertilized ovum.

Question 5

The series of rapid mitotic cell divisions that convert a zygote into a morula are called
A)gastrulation
B)differentiation
C)gravidation
D)cleavage
E)implantation

Accepted Answer

The series of rapid mitotic cell divisions that convert a zygote into a morula are called cleavage.

Question 6

The fetal portion of the placenta is formed by the ____ of the blastocyst.
A)trophoblast
B)inner cell mass
C)zona pellucida
D)yolk sac
E)corona radiata

Accepted Answer

The trophoblast is the outer layer of cells of the blastocyst and gives rise to the fetal portion of the placenta.

Question 7

Embryology refers to the study of development from the fertilized egg through the _____ week of pregnancy.
A)second
B)fifth
C)eighth
D)ninth
E)tenth

Accepted Answer

Embryology refers to the study of development from the fertilized egg through the eighth week of pregnancy.

Question 8

Of the sperm cells introduced into the vagina during sexual intercourse, what percentage actually reach the secondary oocyte?
A)50 percent
B)10 percent
C)5 percent
D)2 percent
E)less than 1 percent

Accepted Answer

Only a small percentage of the sperm introduced during sexual intercourse actually make it far enough to reach the secondary oocyte. Many are hindered by obstacles such as acidic vaginal environment, cervical mucus, and sperm competition. Therefore, less than 1 percent is the most accurate answer.

Question 9

Birth typically occurs ___ weeks after fertilization.
A)30
B)32
C)34
D)36
E)38

Accepted Answer

Birth typically occurs approximately 38 weeks after fertilization, which is about 40 weeks after the start of the woman's last menstrual period.

Question 10

The only fetal blood vessel that carries fully oxygenated blood is the
A)umbilical vein
B)umbilical artery
C)aorta
D)pulmonary trunk
E)common iliac arteries

Accepted Answer

The umbilical vein carries oxygenated blood from the placenta to the fetus, whereas the umbilical artery carries deoxygenated blood from the fetus to the placenta. The aorta carries oxygenated blood from the left ventricle of the heart to the rest of the body, while the pulmonary trunk carries deoxygenated blood from the right ventricle of the heart to the lungs. The common iliac arteries carry oxygenated blood to the lower limbs. Therefore, the only fetal blood vessel that carries fully oxygenated blood is the umbilical vein.

Question 11

Deoxygenated blood carrying fetal waste products exits the body of the fetus through the
A)umbilical veins
B)intervillous spaces
C)umbilical arteries
D)chorionic villi
E)hepatic portal vein

Accepted Answer

The umbilical arteries carry deoxygenated blood from the fetus to the placenta, where it is oxygenated and nutrients are exchanged. The waste products and deoxygenated blood then flow back to the fetus through the umbilical vein.

Question 12

Which of the following statements accurately describe in vitro fertilization?
A)A woman is artificially inseminated with her husband's semen.
B)The husband's semen is used to artificially inseminate a secondary oocyte donor.
C)Fertilization of the oocyte by the sperm takes place in a laboratory dish.
D)A woman is treated with FSH and is then artificially inseminated with donated semen.
E)All of these answer selections describe aspects of in vitro fertilization.

Accepted Answer

In vitro fertilization involves the fertilization of an oocyte by sperm in a laboratory dish, not through artificial insemination with semen from the woman's husband or a donor. Option A refers to artificial insemination, while option B involves the use of a secondary oocyte donor. Option D involves treatment with FSH and artificial insemination with donated semen, which is not necessarily part of in vitro fertilization. Therefore, option C is the only accurate description of in vitro fertilization.

Question 13

The process of implantation of the blastocyst into the endometrium begins to occur approximately ___ days after fertilization.
A)6
B)8
C)10
D)12
E)14

Accepted Answer

Implantation of the blastocyst into the endometrium typically begins around 6 days after fertilization.

Question 14

A secondary oocyte is viable for approximately ___ hours after ovulation.
A)6
B)12
C)24
D)36
E)48

Accepted Answer

A secondary oocyte is viable for approximately 24 hours after ovulation.

Question 15

Which of the following embryonic membranes forms the fetal portion of the placenta?
A)endoderm
B)chorion
C)mesenchyme
D)allantois
E)amnion

Accepted Answer

The chorion is the embryonic membrane that forms the outermost layer of the fetal portion of the placenta. It is formed from the trophoblast cells and surrounds the other embryonic membranes.

Question 16

The corpus luteum continues to secrete progesterone for _____ after fertilization to help maintain pregnancy and to prepare the mammary glands to secrete milk.
A)two weeks
B)six weeks
C)one to two months
D)three to four months
E)nine months

Accepted Answer

The answer of The corpus luteum continues to secrete progesterone...

Question 17

For fertilization to occur, the sperm has to penetrate through the _____ and the zona pellucida.
A)zona glomerulosa
B)zonula occludens
C)corona radiata
D)corona granulosa
E)cumulus oophorous

Accepted Answer

The sperm must first penetrate through the corona radiata, a layer of cells surrounding the oocyte, before it can reach the zona pellucida, a thick glycoprotein layer that surrounds the oocyte. The other options listed are not involved in the process of fertilization.

Question 18

Before a sperm cell can fertilize an ovum, it has to undergo _____, which is a process involving a series of functional changes that occur inside the female reproductive tract.
A)capacitation
B)cleavage
C)somatic cell division
D)attenuation
E)maturation

Accepted Answer

Capacitation is the process that allows the sperm to undergo functional changes that enable it to fertilize the ovum. This process occurs inside the female reproductive tract and prepares the sperm for successful fertilization. The other options are not involved in the process of fertilization.

Question 19

By the beginning of the _____, the placenta consists of two distinct parts including a fetal portion of chorionic villi and a maternal portion formed by the endometrium.
A)fourth week
B)eighth week
C)twelfth week
D)second week
E)first week

Accepted Answer

By the twelfth week of gestation, the placenta has developed into two distinct parts, including a fetal portion composed of chorionic villi and a maternal part formed by the endometrium.

Question 20

Which of the following structures serves as an early site of formation of blood and blood vessels, and is associated with the development of the urinary bladder?
A)yolk sac
B)allantois
C)chorion
D)amnion
E)umbilical cord

Accepted Answer

The allantois is involved in early blood formation and is associated with the development of the urinary bladder.

Quiz 24: Development and Inheritance

The fetal period refers to the time of development extending from the end of the ___ month after fertilization until birth.

The term neonatal period refers to the first ___ days after birth.

Successive cleavages of the zygote produce a solid sphere of small cells called the

Fraternal twins

The series of rapid mitotic cell divisions that convert a zygote into a morula are called

The fetal portion of the placenta is formed by the ____ of the blastocyst.

Embryology refers to the study of development from the fertilized egg through the _____ week of pregnancy.

Of the sperm cells introduced into the vagina during sexual intercourse, what percentage actually reach the secondary oocyte?

Birth typically occurs ___ weeks after fertilization.

The only fetal blood vessel that carries fully oxygenated blood is the

Deoxygenated blood carrying fetal waste products exits the body of the fetus through the

Which of the following statements accurately describe in vitro fertilization?

The process of implantation of the blastocyst into the endometrium begins to occur approximately ___ days after fertilization.

A secondary oocyte is viable for approximately ___ hours after ovulation.

Which of the following embryonic membranes forms the fetal portion of the placenta?

The corpus luteum continues to secrete progesterone for _____ after fertilization to help maintain pregnancy and to prepare the mammary glands to secrete milk.

For fertilization to occur, the sperm has to penetrate through the _____ and the zona pellucida.

Before a sperm cell can fertilize an ovum, it has to undergo _____, which is a process involving a series of functional changes that occur inside the female reproductive tract.

By the beginning of the _____, the placenta consists of two distinct parts including a fetal portion of chorionic villi and a maternal portion formed by the endometrium.

Which of the following structures serves as an early site of formation of blood and blood vessels, and is associated with the development of the urinary bladder?