Chapter 28: Pregnancy and Development

Question 1

Where does fertilization occur?

Answer 1

in the Fallopian tubes

Question 2

From fertilization through week 8, the developing offspring is called _________________

Answer 2

an embryo

Question 3

From week 9 through birth, the developing offspring is called _________________

Answer 3

a fetus

Question 4

Before fertilization can occur, sperm must reach the _________________

Answer 4

the ovulated secondary oocyte

Question 5

What is a fertilized egg called?

Answer 5

a zygote

Question 6

When does a zygote form?

Answer 6

When the DNA of sperm and egg fuse

Question 7

An oocyte is fertilizable for up to _________________ and most sperm are viable within the female reproductive tract for _________________

Answer 7

24 hours, one or two days

Question 8

Sperm must survive the hostile environment of the vagina and become _________________ before fertilzation can occur

Answer 8

capacitated (aka activated)

Question 9

Hundreds of sperm must release their _________________ to break down the egg’s _________________ and _________________

Answer 9

acrosomal enzymes, corona radiata and zona pellucida

Question 10

After the sperm goes inside the oocyte and a cortical reaction occurs and prevents

Answer 10

polyspermy (more sperm from entering)

Question 11

What attracts the sperm to the egg?

Answer 11

positive chemotasxis

Question 12

After sperm penetration, the secondary oocyte completes _________________

Answer 12

meiosis II

Question 13

What is cleavage?

Answer 13

a period of rapid mitotic divisions of the zygote without growing in size.

Question 14

When does cleavage occur?

Answer 14

After the zygote is formed

Question 15

What does cleavage result in?

Answer 15

a morula

Question 16

What is a morula?

Answer 16

A ball of cells (the same size as the zygote) called

Question 17

By day 3-4 of fertilization the morula travels down the falllopian tube and becomes a A ball of cells (the same size as the zygote) called

Answer 17

blastocyst

Question 18

What is a blastocyst?

Answer 18

a fluid filled hollow sphere. OUter cells are called trophoblast cells and on one side inside there is a mass called “inner cell mass”

Question 19

What do trophoblast cells form?

Answer 19

eventually becomes the placenta

Question 20

What 4 things do the inner cell mass form?

Answer 20

1) embryo
2) Amnion
3) Yolk Sac
4) Allantois

Question 21

Define amnion

Answer 21

bag filled with fluid

Question 22

what’s made in the yolk sac?

Answer 22

the first red blood cells

Question 23

What does the allantiois form?

Answer 23

the blood vessels of the umbilical cord (the allantois develops from the gut of the embryo)

Question 24

Where does the blastocyst burry itself?

Answer 24

into the endrometrius

Question 25

Once embedded, the blastocyst forms __________

Answer 25

the chorion

Question 26

What is the chorion?

Answer 26

the outer layer of blastocyst that forms the placenta

Question 27

How long does it take for the placenta to form?

Answer 27

3 months (1st trimester)

Question 28

What does the chorion produce?

Answer 28

hCG hormone (human chorionic gonadotropin)

Question 29

What does hCG do?

Answer 29

keeps the corpus luteum, which keeps estrogen and progesterone levels high)

Question 30

What hormone do pregnancy tests test for?

Answer 30

hCG

Question 31

Define blastula

Answer 31

ball of cells that undergoes gastrulation. The blastocyst is converted to a gastrula when the three primary germ layers form.

Question 32

Define gastrulation

Answer 32

the developmental process that produces the 3 primary germ layers

Question 33

What forms as a result of gastrulation?

Answer 33

the primitive digestive tract (a tube that goes through the gastula, eventually each end of the tube will be the mouth and the anus)

Question 34

What are the three germ layers of a gastula? (from outermost layer to the innermost layer)

Answer 34

ectoderm, mesoderm, and endoderm

Question 35

what does the ectoderm form?

Answer 35

nervous system, pituitary, adrenal medulla, epidermis of skin, eyes, nasal, oral, and anal epithelium

Question 36

What does the mesoderm form?

Answer 36

muscles, bones, connective tissue, cardiovascular system, lymphatic and blood system, urogenital organs, and dermis of skin

Question 37

What does the endoderm form?

Answer 37

GI tract and glands (liver, pancreas, gall bladder), urinary bladder, respiratory epithelium

Question 38

What helps sperm recognize the egg?

Answer 38

bindin

Question 39

Right before fertilization, the oocyte is still in __________

Answer 39

metaphase 2

Question 40

What does the Wolffian Duct System make?

Answer 40

it makes male internal organs (epidiymis, seminal vesicles, prostate)

Question 41

What does the Mullerian Duct System make?

Answer 41

it makes female internal organs (ovaries, uterus, fallopian tubes, vagina)

Question 42

Which system do embryos have?

Answer 42

both the Wolffian and Mullerian Duct System

Question 43

if __________ is present, mullerian develops; by default the external organs are __________

Answer 43

no y is present, female (labia, clitoris)

Question 44

If __________ is present, testes develop, testes in fetus produce __________ and __________

Answer 44

y is present, testosterone and Mullerian inhibiting factor (MIF) (no Mullerian system)

Question 45

Testosterone locally leads to __________

Answer 45

the Wolffian duct system to develop, which develops male internal organs

Question 46

Testosterone systematically (in the whole body) leads to __________

Answer 46

the development of the penis (~7 weeks)

Question 47

``` The same tissue that develops... the testes= penis= bulbourethral glands= scrotum= ```

Answer 47

the testes= ovaries penis= clitoris bulbourethral glands= vestibular glands (lubrication) scrotum=labia

Question 48

There are 2 processes that form sex organs; __________ and __________

Answer 48

one for internal organs and one for external organs