Human Embryology 2 - Development Of Head & Face

Question 1

Fetal membrane composed of

Answer 1

1. Chorion
2. Amnion
3. Yolk sac
4. Allantois
5. Umbilical cord

Question 2

Chorion has three phases of villi

Answer 2

1. Primary
2. Secondary
3. Tertiary

Question 3

In the Decidua capsularis, there is pressure, so overtime the villi in that area of the embryo differentiate into a smooth surface called

Answer 3

Chorion laevae

Question 4

In the Decidua basalis, there is minimal pressure at that end of the embryo and abundant nutrition, so the villi there grow and branch into

Answer 4

Chorion frondosum

Question 5

Chorion frondosum participates in the formation of the

Answer 5

Placenta

Question 6

The placenta of the Decidua basalis comes from the ______ in fetal development

Answer 6

Mother

Question 7

The placenta of the chorion frondosum comes from the ______ in fetal development

Answer 7

Fetus

Question 8

Amniotic fluid is renewed every _______ hours

Answer 8

3

Question 9

Yolk sac composed of

Answer 9

1. Inner Endoderm
2. Outer Extraembryonic Mesoderm

Question 10

Endoderm cells of the yolk sac form ______ which differentiate into spermatogonia and oogonia

Answer 10

Primordial germ cells

Question 11

Mesoderm cells of the walls of the yolk sac differentiate into

Answer 11

Blood island, primary blood vessels & primitive blood cells

Question 12

Outpocketing of the embryo’s gut

Answer 12

Allantois

Question 13

The umbilical cord is about

Answer 13

50cm long

Question 14

Structure by which exchange of material between fetus and mother occurs

Answer 14

Placenta

Question 15

Structures of the placenta
Maternal portion

Answer 15

Decidua basalis

Question 16

Structure of the placenta
Fetal portion

Answer 16

Chorion frondosum

Question 17

The structure between fetal and maternal blood

Answer 17

Placental barrier

Question 18

Placental barrier is comprised of

Answer 18

1. Endothelium
2. Connective tissue
3. Cytotrophoblast
4. Synctiotrophoblast

Question 19

Functions of placenta

Answer 19

1. Exchange
2. Protection
3. Hormone production
   - (HCG) Human Chorionic Gonadotropin
   - (HPL) Human Placental Lactogen
   - Progesterone
   - Estrogen

Question 20

HCG is produced in abundance _____ weeks after fertilization

Answer 20

2

Question 21

Week 4-5 symmetrical columns formed called
6 pairs

Answer 21

Brachial arches

Question 22

Between brachial arches

Answer 22

Brachial clefts

Question 23

Cranial part of the foregut formed from the endoderm

Answer 23

Primitive pharynx

Question 24

At week 4, the neural crest mesenchyme produces five (5) principal prominences named

Answer 24

1. Frontonasal prominence
2. Heart prominence
3. Maximally prominence (pair)
4. Mandibular prominence (pair)
5. All surrounding a Stomodeum

Question 25

Anterior 4 pairs of brachial arches are

Answer 25

Visible

Question 26

The 5th pair of brachial arches

Answer 26

Disappear

Question 27

The 6th pair of brachial arches is

Answer 27

Not visible

Question 28

Brachial apparatus comprised of

Answer 28

1. Brachial arches 2. Brachial cleft 3. Brachial membrane 4. Pharyngeal pouches

Question 29

Base of the Stomodeum

Answer 29

Oropharyngeal membrane

Question 30

By week 6, two additional prominences formed

Answer 30

1. Lateral nasal prominence (pair) 2. Medial nasal prominence (pair)

Question 31

Medial nasal prominence forms

Answer 31

1. Philtrum 2. Medial upper lip 3. Nasal tip 4. Columella

Question 32

Lateral nasal prominence forms

Answer 32

1. Lateral nasal ala 2. Nasolacrimal groove

Question 33

The formation of the palate occurs between

Answer 33

Week 5 - Week 12

Question 34

The frontonasal prominence forms

Answer 34

1. Forehead 2. Bridge and tip of nose 3. Philtrum 4. Primary palate

Question 35

The maxillary prominence forms

Answer 35

1. Lateral part of upper lips 2. Lateral wall and floor of orbit

Question 36

The mandibular prominence forms

Answer 36

1. Mandible 2. Lower lip

Question 37

Malformations of the prominences **very important for exams**

Answer 37

1. Bilateral cleft lip 2. Oblique facial cleft 3. Cleft lip 4.