Lecture 3

Question 1

What is the duration of prenatal development (directly after conception as well as directly after fertilization?)

Answer 1

Duration is 40 weeks from conception, usually 38 weeks from fertilization

Question 2

What are the three zygotic stages of development in order?

Answer 2

1. Germinal Period (Period of the zygote)
2. Embryonic Period (Period of the embryo)
3. Fetal Period (Period of the Fetus)

Question 3

What marks the end of the germinal period? How long does this usually take?

Answer 3

The implantation of the zygote (0 - 14 days, implantation takes roughly 1 week)

Question 4

In what zygotic period can the sex of the baby be determined?

Answer 4

The fetal period

Question 5

What is the role of amniotic fluid?

Answer 5

cushions and helps with temperature regulation

Question 6

What is the first important developmental structure of the fetus?

Answer 6

The neural tube

Question 7

What is the order of development in the period of the embryo?

Answer 7

1. Neural Tube
2. Cardiovascular System
3. Face
4. Urinary System
5. Beginning of Skeletal Development

Question 8

How fast is an am embryonic baby’s heart rate?

Answer 8

120-180 bpm

Question 9

What indicates the end of the embryonic period?

Answer 9

All major systems are present, the first bone cells appear, and there is a complete human form

Question 10

Around which week is the period of the fetus?

Answer 10

9 weeks

Question 11

What is the role of the period of the fetus?

Answer 11

Rapid growth in body size and complexity

Question 12

What is the important supplement for women in the embryonic phase for the closure of the neural tube?

Answer 12

Folic Acid

Question 13

What is the order of eye development in the fetal period?

Answer 13

The eyeballs form -> connect to the brain -> and the fetus is sensitive to light around 16 weeks

Question 14

What is the focal growth point after the eyes begin to develop?

Answer 14

The limbs lengthen

Question 15

Describe the 2 steps of brain development

Answer 15

20 weeks:
Neurons are all formed, myelination will begin, cortical cells are forming (folds)
27 weeks:
Synaptogenesis
Myelination
Specialization of lobes

Question 16

Define synaptogenesis and myelination

Answer 16

Synaptogenesis is the establishment of connections between neurons, and myelination is the deposit of myelin on the nerve axons that insulate and speed up signal transmission

Question 17

What organs develop after the brain? What two other growth processes are observed during this time?

Answer 17

The skin and lungs.
1. Motor behaviours such as sucking are also observed
2. The fetus gains fat

Question 18

How is auditory reception tested during pregnancy?

Answer 18

Fetal blinking in response to noise

Question 19

What are the three reasons for abnormal prenatal development?

Answer 19

1. Maternal Environment
2. Teratogens
3. Genetic issues

Question 20

What is it called when the zygote implants in he fallopian tubes?

Answer 20

An Ectopic pregnancy

Question 21

What are the risks associated with a breech birth?

Answer 21

The umbilical cord is compressed or around the neck

Question 22

What are the leading theories as to why maternal stress impacts fetal development?

Answer 22

1. Blood is drawn to the mothers organs instead of development
2. Stimulant hormones cross the placenta
3. Stress is correlated with other risk factors such as drugs

Question 23

What is rH factor incompatibility in pregnancy? How is this risk mitigated?

Answer 23

Baby blood causes mom to develop antibodies for following babies. There are vaccines available now to reduce the effect.

Question 24

What are 4 vitamins essential to prenatal development?

Answer 24

Iron, Folic Acid, Vitamin D, and fatty acids

Question 25

Define a teratogen

Answer 25

An environmental agent that causes fetal damage during the prenatal period

Question 26

When do teratogens do the most damage? What developmental period is this?

Answer 26

During sensitive periods such as organogenesis. Teratogens are most potent in the embryonic period.

Question 27

What are the three types of teratogen?

Answer 27

Disease, Drugs, and Toxins

Question 28

What 5 diseases are covered in the class?

Answer 28

1. Rubella
2. STDs
3. HIV/AIDS
4. Toxoplasmosis
5. Malaria

Question 29

What is significant about Rubella? What is its defining effect?

Answer 29

A high proportion (half) of moms with it had kids with physical birth defects of eyes, heart, intestines, and urinary systems

Question 30

What are some associated risks with pregnancy with an STD

Answer 30

Risk of ectopic pregnancy, motor development, formation of major systems

Question 31

How can HIV/AIDS be transmitted to a fetus?

Answer 31

Through placenta or also breast milk

Question 32

What is the first drug found to be a teratogen?

Answer 32

Thalidomide was taken as a morning sickness pill

Question 33

What drug is associated with genital/reproductive organ poor development/cancer?

Answer 33

DES

Question 34

What acne drug is a teratogen?

Answer 34

Accutane

Question 35

What common drugs are associated with LBW and miscarriage?

Answer 35

Aspirin and Caffeine

Question 36

What are some effects of FASD?

Answer 36

Cognitive effects:
Mental retardation, poor attention, hyperactivity
Physical Effects:
Facial abnormalities, slow growth

Question 37

What drugs can leave babies with withdrawal-like symptoms? (low eye contact, not cuddly, irritable)

Answer 37

Cocaine, Heroin, Meth

Question 38

What is the mechanism of teratogenesis with nicotine? What is a special consequence associated with nicotine?

Answer 38

It causes poor placenta growth which restricts oxygen levels. It is associated with SIDS

Question 39

What are four environmental toxins? What part of development do they effect mostly?

Answer 39

radiation, lead, PCBs, and Mercury all affect neural development