Chapter 6 - Conception and Prenatal Development

Question 1

Gametes =

Somatic cells =

Answer 1

Gametes = sex cells.

Somatic cells = body cells.

Question 2

Mitosis = def

Answer 2

diploid number of chromosomes (46)is retained in the new cell

Question 3

Meiosis - what happens?

Answer 3

23 chromosomes (not all, half) are made.

Question 4

Oogenesis - def

Answer 4

formation of female gametes

Question 5

Primary oogonium begins its first meiotic division during fetal life but doe snot complete the process until ____

Answer 5

Puberty

Question 6

By the 30th week of gestation, the female fetus has all the ova she will ever have. T/F?

Answer 6

True

Question 7

What is spermatogenesis?

Answer 7

The formation of sperm

Question 8

Sperm determines the sex of the baby. T/F?

Answer 8

True

Question 9

Before ovulation, several oocytes begin to mature under the influence of FSH and LH. T/F?

Answer 9

True

Question 10

Sperm - they don’t go through any changes once they enter the vajeen. T/F? What is it called?

Answer 10

FALSE - they have to go through some changes, called capacitation.

Question 11

When is the pre-embryonic period?

Answer 11

First 2 weeks after conception.

Question 12

Around the 4th day after conception, the fertilized ovum, now called a _____, enters the uterus.

Answer 12

ZYGOTE

Question 13

What is the conceptus?

Answer 13

Cells and membranes resulting from fertilization of the ovum)

Question 14

Morula - def?

Answer 14

12-16 cell stage of the fetus

Question 15

What is the decidua?

Answer 15

Endometrium during pregnancy

Question 16

Implantation and survival of the conceptus requires a continuing supply of __ and ___

Answer 16

Estrogen and progesterone.

Question 17

The zygote secretes ___ to tell the woman’s body that she’s pregnant!

Answer 17

HCG

Question 18

Normal implantation occurs in the __ uterus.

Answer 18

Upper

Question 19

A small amount of bleeding can occur as the zygote implants…T/F?

Answer 19

True - which is why some women think they’ve actually had their period

Question 20

Embryo - week __ to __

Answer 20

3-8

Question 21

During the embryonic phase, structure are particularly at risk for harm by __

Answer 21

Teratogens - because they’re developing so fast!

Question 22

Embryo’s develop - cephalocaudal, central to peripheral and simple to complex. T/F?

Answer 22

True

Question 23

What is a full-term baby?

Answer 23

36-40 weeks of fertilization age or 38-42 weeks of gestational age.

Question 24

Fertilization age - approximately 2 weeks longer than the gestational age. T/F?

Answer 24

FALSE - it’s shorter.

Question 25

Implantation is complete by the end of the ___ week after fertilization.

Answer 25

2nd

Question 26

The CNS begins developing during the __ week.

Answer 26

3rd

Question 27

The primitive/tubular heart begins beating at day __ to __.

Answer 27

22-23

Question 28

Neural tube closes during the ____ week - if not, problems occur.

Answer 28

4th

Question 29

When is the fetal period?

Answer 29

9 weeks after conception and ends with birth.

Question 30

Weeks 13-16 - what is quickening?

Answer 30

First fetal movements.

Question 31

Weeks 21-24 - lungs are beginning to produce ___.

Answer 31

Surfactant - makes it easier to breathe.

Question 32

Weeks 25-28 - baby starts to move head down. T/F/

Answer 32

True

Question 33

Maternal and fetal blood typically don't mix in the placenta, however......

Answer 33

They can! Like if there's trauma, or during childbirth, etc.

Question 34

Fetal HgB can carry 20-50% more oxygen than adult hemoglobin. T/F?

Answer 34

True

Question 35

What is the bag of waters?

Answer 35

Two fetal membranes - the amnion (inner) and chorion (outer)

Question 36

Amniotic fluid - about ___ ml by end of pregnancy.

Answer 36

700-800

Question 37

Umbilical vein - action | Umbilical artery - action

Answer 37

Vein = brings oxygen and nutrient rich blood back to the placenta. Artery - takes waste and such away from placenta, back to the mom.

Question 38

What are the 3 blood shunts in the baby?

Answer 38

Ductus venosus, foramen ovale, ductus arteriosus.

Question 39

What does the ductus venosus do?

Answer 39

Shunts blood away from the liver.

Question 40

What does the foramen ovale do?

Answer 40

Shunts the blood through the heart - bypasses the lungs.

Question 41

What does the ductus arteriosus do?

Answer 41

Shunts the blood from the aorta - we don't need as much systemically.

Question 42

Monozygotic twins are conceived by the union of a single ovum and spermatozum - T/F/

Answer 42

True

Question 43

What are dizygotic twins?

Answer 43

Twins that arise from two ova and they are fertilized by two sperm.