Ch.5 Embryology Flashcards

Front 1

Which of the following structures is the most substantial contributor to the diaphragm?

Back 1

Septum Transversum

Front 2

Prior to the head fold, the anterior to posterior order of these structures is

Back 2

Septum transversum, heart primordium, oropharyngeal membrane, neural plate

Front 3

After the head fold, the anterior to posterior order of these structures is

Back 3

Neural plate, oropharyngeal membrane, heart primordium, septum transversum

Front 4

A neonate has a normal physical examination except for amputation distruptions of finders 2-5 on the right hand. Digits 3-5 have only nubbins remaining, but a fleshy band of tissue is wrapped around the hypoplastic digit 2. The mother was on hormone supplements before she knew she was pregnant, and has read that progesterone can cause limb defects. Your best response is to:

Back 4

Explain that this is an amniotic band disruption with minimal recurrence risk and no relation to hormone therapy

Front 5

The change in orientation of structures by the tail fold is most accurately described as

Back 5

Allantois-cloacal membrane-neural plate to neural plate-cloacal-membrane-allantois

Front 6

The lateral fold brings which of the following gorups os structures into the umbilical cord?

Back 6

Yolk sac, allantios, connecting stalk mesoderm

Front 7

After the lateral folds are completed, the ventral separation of peritoneal cavity and amnion is composed of what structures?

Back 7

Somatic layer of lateral plate mesoderm and surface ectoderm, called jointly the somatopleure

Front 8

A neonate presents with an open cranium, virtually no skull above the eye brows, and disorganized neural tissue within the cranial opening. The embryonic origin of this anomaly is

Back 8

Failed closure of the cranial neuropore at about 4 weeks post fertilization

Front 9

The first signs of ear an deye development visible on the embryonic surface are the

Back 9

Lens placode and otic placodes

Front 10

This structure contains the major artery to each section of the gut

Back 10

Dorsal mesentery

Front 11

This structure disappears excepts near the distal portion of the esophagus

Back 11

Ventral mesentery

Front 12

This structure contains planchnic lateral plate mesoderm and gut endoderm

Back 12

Splanchnopleure

Front 13

This sturcture divides the peritoneal cavity ventrally in certain portions of the embryo

Back 13

Ventral mesentery

Front 14

This structure separates the pleural and peritoneal cavities

Back 14

Pleuroperitoneal membrane

Front 15

This structure contributes to the diaphragm

Back 15

Pleuroperitoneal membrane

Front 16

The intervillous spaces of the placenta derive from

Back 16

Lacunae in the synctiotrophoblast

Front 17

Which sequence best describes the maternal placental circulation?

Back 17

Sprial arteries, intervillous spaces, endometrial veins

Front 18

Which sequence best describes the feto-placental circulation?

Back 18

Stem villi, umbilical vein, fetal heart, umbilical artery

Front 19

Which group of structures constitutes the placental membrane that is interposed between the fetal and maternal circlations?

Back 19

Synctiotrophoblast, cytotrophoblast, connective tissue in the chorionic villus, endothelium of the fetal capillaries

Front 20

A neonate exhibits severe respiratory distress in the delivery room. A chest x-ray shows the outlines of intestines and intestinal gas in the left chest, compressing the heart and lungs. The child cannot be resuscitated, and expries with severe acidosis and hpyoxia. The likely cause of death is

Back 20

Congential disphragmatic hernia with inadequate lung volume due to fetal underdevelopment of the lungs

Front 21

Persists as a Meckel diverticulum in 2% of individuals

Back 21

Yolk sac

Front 22

Involutes to become the median umbilical ligament

Back 22

Allantois

Front 23

May accumulate extra fliud with anomalies such as duodenal atresia

Back 23

Amnion

Front 24

Premature separation from decidua may cause fetal death

Back 24

Placenta

Front 25

May persist as the urachus

Back 25

Allantois

Front 26

One-fourth of their DNA is identical

Back 26

Superfecundation

Front 27

Identical DNA with shared body parts

Back 27

Conjoined twins

Front 28

Identical DNA, very different sizes

Back 28

Parasitic twins

Front 29

One-half of their DNA is identical

Back 29

Dizygotic twins

Front 30

Always two amnions and two chorions

Back 30

Dizygotic twins

Front 31

Somites

Back 31

pictures on pg15 of E5

Front 32

First branchial arch

Back 32

pics on pg15

Front 33

Lens placode

Back 33

pics on pg15

Front 34

If you were asked to counsel a couple regarding the fetus shown in Fig. 5-1, the most likely diagnosis and recurrence risk would be

Back 34

Amniotic band disruption with multiple anomalies, <1% risk for amniotic band disruption in future pregnancies