prenatal development

Question 1

the three stages of prenatal development

Answer 1

zygote
embryo
fetus

Question 2

the conception stage does?

Answer 2

continuation from conception and when we don’t know exactly when conception is we us an estimation from when the persons last period was.

Question 3

when deciding the conception date what do we add

Answer 3

we add 2 weeks

Question 4

conception

Answer 4

you should begin planning 3 months before you want to become pregnant.
- (you want to get off of contraceptives 3 months before wanting to be pregnant)
- the body should also be getting healthy

Question 5

the period of the zygote

Answer 5

• lasts about 2 weeks from fertilization

‣ Fertilization typically occurs within whichever fallopian tube it goes into

Question 6

parts of the period of the zygote

Answer 6

◦1) Duplication - 30 hours for the first duplication
◦2) blastocyst - 4th day made of 60-70 cells
‣ A) embryonic disk - inner cells
‣ B) trophoblast - protective covering and nutrition for the organism
◦3) implantation - between day 7 and 9
‣ Egg will implant into the uterine lining
* If it happens too early you can run into an ectopic pregnancy when the zygote implants onto the outside of the uterus instead of the inside. Often it is not compatible and does not make it.

Question 7

the period of the embryo

Answer 7

• 1. implantation through the 8th week of pregnancy
     ◦Development of the embryonic disk occurs - the inner cells of the blastocyst
     ‣ Endoderm becomes - (gut) digestive system, liver, pancreas, lungs (inner layers)
     ‣ Mesoderm becomes - circulatory system, lungs (epithelial layers), skeletal system,
     muscular system
     ‣ Ectoderm becomes - hair, nails, skin, nervous system

Question 8

neural tube formation

Answer 8

◦Ectoderm folds over to produce a primitive neural tube
‣ Super essential part of our development
◦At this stage the embryo is at high risk for issues

Question 9

neural tube development - cleft lip/palate

Answer 9

‣ When there is an issue with growth at the top cleft lip appears.
‣ Cleft palate causes people to be susceptible to a lot of things. You can’t suckle from a
bottle or breast. When they do feed the baby can aspirate their food into their passages
and into their lungs/respiratory system. Everything from your nasal passages like phlegm
and mucus will drip into the mouth.

Question 10

neural tube development - spina bifida

Answer 10

‣ A problem at the bottom causes spina bifida. It is when there is not a proper closure at
the bottom. Depending on how far it is from the bottom determine how severe it is.
* Some people may not have bladder control, some may have a lot of pain and others
no pain, and some may become paralyzed.
◦Can do surgery on this while the baby is in utero. This is pretty risky but can be
effective.
‣ Most neural tube defects at the top or bottoms can be neutralized with
adequate amounts of folic acid in the diet.

Question 11

organ formation in the period of the embryo

Answer 11

• 3. Heart pumping
• 4. Organ formation
     ◦At the end of the first month, the curled embryo consists of organized cells with specific functions, but is only 1/4 inch long

‣ Weeks 3 & 4: heart and embryonic blood vessels begin to develop, embryonic circulation is established, the heart begins to beat, cardiac looping is completed
‣ Week 5: partitioning of the heart into 4 chambers begin
‣ Week 6: aortic arches undergo primary changes to the adult form
‣ Week 8: formation of the heart valves is complete

Question 12

the second month of pregnancy - embryo

Answer 12

◦Eyes, nose, jaw and neck form (but no bones yet)
‣ A. Limb buds
‣ B. Intestines grow
‣ C. Heart develops chambers
‣ D. Liver and spleen produce blood cells
‣ E. Basic sensation - responds to touch on mouth and soles of feet- at the end of the
second month is more upright 1/7 ounces and 1 inch long
* Spontaneous miscarriages will still happen (most still wont have announced thy are
pregnant)

Question 13

third month of pregnancy - embryo

Answer 13

◦A. Organs communicate one another
◦B. Lungs expand and contrast
◦C. Kicking, toe curling, opens mouth, thumb sucking
◦D. External genitalia by week 12
◦E. Fingernails, tooth bud, eyelids
‣ We will start calling it a fetus now (partially because it is starting to look like a baby)

Question 14

when do we start calling a baby in utero a fetus

Answer 14

after the third month

Question 15

the period of the fetus

Answer 15

the second trimester 4-6 months
‣ Most neurons in place
‣ Sensitive to sounds and light

Question 16

the period of the fetus - quickening

Answer 16

• When the woman is first considered pregnant. Use to think it was only problematic
  to try to get rid of a baby if they had already reached the ‘quickening’ stage. When
  others can really see the person is pregnant.

Question 17

the period of the fetus - vernix

Answer 17

• A white cheesy substance that is a coating or something. The idea is that this vernix
  protects the skin from breaking down from being in the liquid in utero. An oily
  coating that serves as protection.
  ◦Most of it will rub off after being born, comes off over time and May mostly
  come off inside the birth canal.

Question 18

the period of the fetus - lanugo

Answer 18

• A very very thin hair that the fetus especially in the 4-6 months will have all over the
  body. (The trees and plants that keep the soil from eroding)
  ◦Purpose is to provide the roots for the vernix to be on the body. Can also help
  the fetus to maintain temperature of their body

Question 19

the third trimester - 7-9 months

Answer 19

‣ A. The age of viability 22-26 weeks
* Viability is the ability to live outside of the womb if born right then
‣ B. Development of the cerebral cortex
‣ C. Cycles of alertness
* Will be awake and alert almost in direct opposition with the mothers movement and
tendency levels. When the mom is doing things the paper is likely to be sleeping,
when the mom is laying still of not doing much the baby is likely to sleep. (This is
what a healthy fetus does)
‣ D. Pain sensation begins
‣ E. Can start to distinguish the mothers voice
‣ F. Temperament in the womb

Question 20

parts of pain sensation in the third trimester

Answer 20

• Used to be thought that prenatally (or premature) they wouldn’t experience pain.
  Stating that they aren’t drying or screaming, really because their tear ducts and
  lungs aren’t fully developed. They quite literally can’t cry.

Question 21

cycle of alertness in the third trimester

Answer 21

• Will be awake and alert almost in direct opposition with the mothers movement and
  tendency levels. When the mom is doing things the paper is likely to be sleeping,
  when the mom is laying still of not doing much the baby is likely to sleep. (This is
  what a healthy fetus does)