Fertilization

Question 1

Mitosis

Answer 1

Body cells

Exact copies

Daughter cells have 46 chromosomes (diploid)

Question 2

Meiosis

Answer 2

Gametes (sex cells)

Exchange of material btw chromatids results in genetic variation

2 divisions resulting in 4 daughter cells with each daughter cell having 23 chromosomes (haploid)

Question 3

Fertilization

Answer 3

Haploid gametes (sperm and ovum) join together in Ampulla of Fallopian Tubes

Question 4

Sperm Capacitation

Answer 4

Removal of plasma membrane aided by uterine enzymes

BOOSTER

Question 5

Sperm Acrosomal Reaction

Answer 5

Enzymes lots of sperm produce to allow one to enter Zona Pellucida

TEAMWORK

Question 6

Once one sperm enters the Zona Pellucida, what does the Zona Pellucida do?

Answer 6

Releases enzymes so no other sperm can enter

SEALS OFF THE ENTRANCE!

Question 7

Does the sperm or the ovum determine X or Y chromosomes for zygote?

Answer 7

Sperm

Question 8

Implantation

Answer 8

Rapid mitotic division of the fertilized cell

“Cleavage” forms Blastomeres

Blastomeres grow to Morula (solid ball of 12-32 cells)

Morula divides into inner solid mass (Blastocyst) surrounded by outer layer of cells (Trophoblast)

Question 9

What is the period in which implantation in the uterus occurs?

Answer 9

7-10 days

Question 10

10-14 Days After Conception

Answer 10

Blastocyst differentiates into 3 primary germ layers (Ectoderm, Mesoderm, Endoderm)

All tissues, organs, and organ systems develop from these primary germ cell layers

Question 11

Embryonic Membranes

Answer 11

Develop to protect and support embryo

Chorion - first to develop from trophoblast

Amnion - from ectoderm and contains amniotic fluid

Question 12

Yolk Sac

Answer 12

Forms RBCs until liver works about 6 weeks and then becomes part of umbilical cord

Question 13

What becomes part of the umbilical cord after 6 weeks?

Answer 13

Yolk Sac

Question 14

Fraternal Twins

Answer 14

Dizygotic

2 separate ovum fertilized by 2 sperm

2 placentas, chorions, amnions

Question 15

Identical Twins

Answer 15

Monozygotic

1 fertilized egg (1 zygote that separates into 2)

Question 16

Di-Di Identical Twins

Answer 16

2 embryos, amnions, and chorions (day 3)

Question 17

Mono-Di Identical Twins

Answer 17

2 embryos and amnions but 1 chorion (day 5)

Question 18

Mono-Mono Identical Twins

Answer 18

2 embryos, 1 amnion and chorion (day 8)

Question 19

Umbilical Cord

Answer 19

Develops from amnion

Body stalk attaches embryo to yolk sac, fuses w/ embryonic portion of placenta

Surrounded by Wharton Jelly

Question 20

Wharton Jelly

Answer 20

Gelatinous

To protect vessels

Question 21

How many arteries and veins does the umbilical cord have?

Answer 21

AVA

2 arteries and 1 vein

Question 22

Arteries in Umbilical Cord

Answer 22

Are deoxygenated blood

Question 23

Veins in Umbilical Cord

Answer 23

Are oxygenated blood

Question 24

Umbilical Cord Function

Answer 24

Provides circulatory pathway to embryo

Question 25

Placenta

Answer 25

2 sides - maternal & fetal Develops at the third week of embryonic development Develops at site where embryo attaches to uterine wall

Question 26

Placenta Functions

Answer 26

Metabolic activities Transports substances Endocrine function: hCG, hPL, relaxin, inhibitin, estrogen, progesterone

Question 27

What happens to the corpus luteum when the placenta is developed?

Answer 27

It goes away and the placenta takes over by producing estrogen and progesterone

Question 28

Do maternal and fetal blood mix under normal situations or not?

Answer 28

They DO NOT mix

Question 29

Fetal Development

Answer 29

Zygote/Pre-embryonic Phase - first 2 weeks after conception Embryo - start of week 3 to end of week 8 Fetus - week 9 to birth

Question 30

4 Weeks Fetal Development

Answer 30

Fetal heart begins to beat

Question 31

8 Weeks Fetal Development

Answer 31

All body organs are formed

Question 32

8-12 Weeks Fetal Development

Answer 32

Fetal heart rate can be heard by ultrasound Doppler device

Question 33

16 Weeks Fetal Development

Answer 33

Sex organs can be seen Fetal movement (quickening) felt

Question 34

20 Weeks Fetal Development

Answer 34

Hands can grasp Favorite position in utero (lie) established Vernix caseosa (lanolin-like covering) protects the body Lanugo (fine hair) keeps oil on skin Head hair, eyebrows, and eyelashes present

Question 35

24 Weeks Fetal Development

Answer 35

Fetal respiratory movements begin

Question 36

28 Weeks Fetal Development

Answer 36

Eyes open and close Surfactant is formed

Question 37

32 Weeks Fetal Development

Answer 37

Fingernails and toenails present Subcutaneous fat is being laid down

Question 38

37+ Weeks Fetal Development

Answer 38

Full term

Question 39

Why do baby's lose weight after they are born?

Answer 39

Because their lungs are filled with water and when they are born it is removed

Question 40

First Trimester

Answer 40

About 0-12 weeks

Question 41

Second Trimester

Answer 41

About 13-27 weeks

Question 42

Third Trimester

Answer 42

About 28-40 weeks