8.4-8.5

Question 1

A 9-month process transforms a single cell into a complete infant. - During this time, external factors significantly impact the developing baby.

Answer 1

Prenatal Development

Question 2

• When an egg (ovum) and a sperm unite, they form a zygote.

Answer 2

Fertilization

Question 3

: The zygote contains 46 chromosomes, which carry genetic information.

Answer 3

Chromosomes

Question 4

: Through mitotic division, the zygote splits into multiple cells, each retaining the same 46 chromosomes.

Answer 4

Mitosis

Question 5

Originated from a single fertilized egg (zygote).
Early in the division process, the zygote splits into two separate masses.
Each mass develops into a separate infant.
Identical features and same sex due to possesing the same set of 46 chromosomes.

Answer 5

Monozygotic (Identical) Twins

Question 6

Accidental timing.
Common in older women and certain ethnic groups.
Results from either releasing more than one egg simultaneously or ovulating again after conception.
If two eggs are fertilized, the woman may giv birth to fraternal twins (two zygotes), triplets, or more.
Increased likelihood in women taking fertility drugs.

Answer 6

Dizygotic (Fraternal) Twins

Question 7

Multiple pregnancies often lead to premature birth. The more babies a woman carries, the higher the risk of delivering before 37 weeks.

Answer 7

Premature birth:

Question 8

Babies from multiple pregnancies are at risk of having ___, affecting their overall development.

Answer 8

Low birth weight:

Question 9

Expectants mothers with multiple pregnancies require more frequent check-ups to monitor signs of early labor or other complications.

Answer 9

Increased doctor visits:

Question 10

Doctors may recommend ____of some fetuses to improve the chances of survival for the remaining infants.

Answer 10

Selective termination:

Question 11

The ethical and moral implications of such decisions fall within _____, which explores how advances in biology and medicine should influence policies and practices

Answer 11

Bioethics concerns:

Question 12

• Sets the stage for a child’s future health and well-being. The entire prenatal period plays an important role in shaping the developing baby.

Answer 12

Prenatal Development

Question 13

Stages of Prenatal Development

Answer 13

Germinal, Embryonic, Fetal

Question 14

2-week period
Begins at conception when the sperm fertilizes the egg.

Answer 14

Germinal Period

Question 15

The fertilized egg, known as a ____, starts dividing and moves down the fallopian tube toward the uterus.

Answer 15

Germinal Period, zygote

Question 16

The zygote differentiates into two distinctive masses: the outer cells (which become the ___) and the inner cells (forming the ____).

Answer 16

placenta; embryo

Question 17

The ____, composed of three layers (____), arrives in the uterus and attaches to the uterine wall through a process called ____.

Answer 17

blastocyst, ectoderm, endoderm, and mesoderm, implantation

Question 18

_____ establishes a connection between the developing organism and the mother’s blood supply via the ____ and ____.

Answer 18

Implantation; placenta; umbilical cord

Question 19

From approximately the third week until the eighth week of pregnancy.
The neural tube forms, laying the foundation for the nervous system.
The embryo undergoes rapid growth and differentiation.
Critical structures such as the heart, brain, and limbs take shape.

Answer 19

Embryonic Period

Question 20

As soon as the embryo begins to receive nourishment from the mother through the placenta, it becomes vulnerable to hazards such as diseases, drugs, and toxins. During critical periods, when major organs are forming, these effects become devastating on the development of the infant.

Answer 20

Critical Period

Question 21

• Birth defect caused by any substance such as drug, chemical, virus, or other factors.

Answer 21

Teratogen

Question 22

Common tetrogens is alcohol. Consumption of alcohol during pregnancy can lead to pysical, mental, and behavioral problems.

Answer 22

Fetal Alcohol Spectrum Disorders (FASDs) -

Question 23

Timeline of the critical periods during early development.

Answer 23

2 to 5 weeks - Central Nervous System
2 to 6 weeks - Heart
3 to 8 weeks - Arms and legs
3 to 8 weeks - Eyes
7 to 12 weeks - Teeth and roof of the mouth

Question 24

From the ninth week until birth
Continued growth and refinement of organs and body systems.
Physical development prepares the fetus for life outside the womb.
The fetus becomes responsive to external stimuli, including sound and touch.
By the end of this period, the fetus is fully formed and ready for delivery.

Answer 24

Fetal Period

Question 25

By the 38th week, the fetus is considered

Answer 25

full term.

Question 26

Most babies are born between ___of gestation

Answer 26

38 and 40 weeks

Question 27

Babies born before 38 weeks are termed ____
These infants may require life support to survive.
Might face long-term issues, especially if their birth weight is less than___

Answer 27

preterm or premature; 5 ½ pounds.

Question 28

Refers to the point at which an infant can potentially survive outside the womb.

Answer 28

Age of Viability:

Question 29

It typically falls between ___ of gestation.
Survival odds increase from ___ at 22 weeks to approximately ___ at 26 weeks.

Answer 29

22 and 26 weeks; 10%; 85%

Question 30

Refers to the unexpected ending of a pregnancy within the first 20 weeks of gestation.
Most miscarriages occur during the first trimester of pregnancy.

Answer 30

Miscarriage; spontaneous abortion