Fetal Development/Genetics

Question 1

What must happen with the female for conception to occur?

Answer 1

A healthy ovum is released from the ovary, passes into an open fallopian tube, and starts its journey downward

Question 2

What is the area where fertilization takes place?

Answer 2

Sperm from the male is deposited into the vagina and swims approximately 7 inches upward to meet the ovum at the outer most portion of the fallopian tube

Question 3

How long does it take for the ovum to reach the cervix?

Answer 3

an hour

Question 4

How long does the process of fertilization typically take?

Answer 4

5 hours

Question 5

Pre-embryonic Stage

Answer 5

fertilization through the second week

Question 6

What are the 3 stages of fetal development during pregnancy?

Answer 6

• Pre-embryonic
• Embryonic
• Fetal

Question 7

When does fertilization typically occur?

Answer 7

around 2 weeks after the last normal menstrual cycle

Question 8

Morula

Answer 8

16 cells appearing as a solid ball of cells
“little mulberry”
Reaches the uterine cavity about 72 hours after fertilization

Question 9

Blastocyst

Answer 9

appears within the morula as an off-centered, fluid filled space, transforming into a hollow ball of cells
-inner surface will form the embryo and amnion

Question 10

Trophoblast

Answer 10

outer layer of cells surrounding the blastocyst cavity

Question 11

What will the trophoblast develop into?

Answer 11

one of the embryonic membranes, the chorion, and helps to form the placenta

Question 12

What will the inner surface of the blastocyst develop into?

Answer 12

Will form the embryo and amnion

Question 13

What will attach its self to the endometrium for implantation?

Answer 13

trophoblast

Question 14

Where does implantation typically occur?

Answer 14

Fundus

Question 15

What are the 3 embryonic layers of cells formed?

Answer 15

Ectoderm
Mesoderm
Endoderm

Question 16

Ectoderm

Answer 16

forms the central nervous system (CNS), special senses, skin, and glands

Question 17

Mesoderm

Answer 17

forms the skeletal, urinary, circulatory, and reproductive systems

Question 18

Endoderm

Answer 18

forms the respiratory system, liver, pancreas, and digestive system

Question 19

What two fetal membranes form the fluid-filled amniotic sac?

Answer 19

Amnion and chorion

Question 20

How much fluid can the amniotic sac hold at full term?

Answer 20

1 L

Question 21

What is amniotic fluid derived from?

Answer 21

Maternal blood and fetal urine

Question 22

Embryonic Stage

Answer 22

begins at day 15 after conception and continues through week 8

Question 23

Week 3 Gestation

Answer 23

Beginning development of brain, spinal-cord, heart, and GI tract
-Leg and arm buds appear and grow

Question 24

Week 4

Answer 24

Brain differentiates

Stomach, pancreas, and liver begin to form

Question 25

Week 5

Answer 25

Heart beat has regular rhythm Beginning structures of eyes and ears Some cranial nerves visible Muscles innervated

Question 26

Week 6

Answer 26

``` Beginning of lungs Fetal circulation Liver produces RBC's Primitive skeleton forms CNS forms Brain waves detectable ```

Question 27

Week 7

Answer 27

``` Straightening of trunk Nipples and hair follicles form Elbows and toes visible Arms and legs move Diaphragm formed Heart beat can be heard Mouth with lips and early tooth buds ```

Question 28

Week 8

Answer 28

Rotation of intestines Facial features develop Heart development complete Resembles a human being

Question 29

Weeks 9-12

Answer 29

``` Sexual differentiation continues Buds for all 20 temporary teeth formed Digestive system shows activity Head comprises is nearly half the fetus size Face and neck are well formed Urogenital tract complete Red blood cells produced in liver Urine is produced and excreted Fetal gender can be determined Limbs long and thin; digits formed ```

Question 30

Weeks 13-16

Answer 30

``` Lanugo hair Fetal skin is almost transparent Bones become harder Sucking motions Amniotic fluid is swallowed Fingernails/toenails Weight quadruples Mom can feel movement ```

Question 31

Weeks 17-20

Answer 31

``` Rapid brain growth Fetal heart tones heard w/ stethoscope Vernix ceseosa covers the fetus Eyebrows and head hair Sebaceous glands Brown fat Muscles well developed ```

Question 32

Weeks 21-24

Answer 32

``` Eyebrows and eyelashes Grasp and startle reflex Alveoli forming in lungs Skin is translucent and red Lungs begin to produce surfactant ```

Question 33

Weeks 25-28

Answer 33

``` Fetus reaches length of 15 inches Rapid brain development Eyelids open and close Nervous system controls some functions Fingerprints are set Blood formation shifts from spleen to bone marrow Usually assumes head-down position ```

Question 34

Week 29-32

Answer 34

``` Rapid increase in body fat Increased CNS control Rhythmic breathing movements occur Lungs are not fully mature Stores iron, calcium, phosphorus ```

Question 35

Week 33-38

Answer 35

``` Testes are in scrotum of male fetus Lanugo begins to disappear Increase body fat Small breast buds present Mother supplies fetus w/ antibodies Considered full term at 38 wks Fills uterus ```

Question 36

Oligohydramnios

Answer 36

too little amniotic fluid (< 500 mL)

Question 37

What can happen due to oligohydraminos?

Answer 37

uteroplacental insufficiency, fetal renal abnormalities, higher risk of surgical births, and low birth weight