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Flashcards in Exam II Deck (105)
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1
Q

The process by which the bilaminar disc is converted to a trilaminar disc

A

Gastrulation

2
Q

This process marks the beginning of morphogenesis.

A

Gastrulation

3
Q

What genes play a role in gastrulation?

A

Shh (sonic hedgehog) and Wnts

4
Q

Epiblast cells proliferate on the midline of the disc and form a narrow streak that runs down the disc. This structure is known as what?

A

Primitive streak

5
Q

This structure is located in the middle of the primitive streak.

A

Primitive groove

6
Q

This structure is located at the end of the groove in the primitive streak.

A

Primitive pit

7
Q

This embryonic layer is formed when epiblasts stay on the top layer of the embryo.

A

Ectoderm

8
Q

This embryonic layer is formed by the migration of epiblasts through the primitive groove into the middle layer of the embryo.

A

Mesoderm

9
Q

This embryonic layer is formed when epiblasts displace the hypoblasts in the lower layer of the embryo.

A

Endoderm

10
Q

What are the three layers of the gastrula?

A

Ectoderm, mesoderm, and endoderm

11
Q

The prechordal plate (forms the mouth) develops at this end of the embryo

A

Cranial end

12
Q

The cloacal plate (future anus, urinary, and genital tracts) develops at this end of the embryo.

A

Caudal end

13
Q

This is the area where the future heart will develop.

A

Cardiogenic area

14
Q

What is the most common tumor in newborns?

A

Sacrococcygeal teratoma

15
Q

This midline cord of cells is formed from mesoderm, which was previously formed at the primitive node, migrating cranially.

A

Notochord

16
Q

The notochord grows until it reaches what?

A

Prechordal plate

17
Q

This is the small portion of the notochord, which persists after the majority disappear.

A

Nucleus pulposus

18
Q

This the formation of vascular channels

A

Vasculogenesis

19
Q

This is the formation of vessels

A

Angiogenesis

20
Q

This structure consists of a core of cytotrophoblasts covered by syntrophoblasts.

A

Primary chorionic villi

21
Q

This structure consists of mesodermal cells penetrating the core of the cytotrophoblasts of the primary villi.

A

Secondary chorionic villi

22
Q

This structure is used to describe the mesodermal core differentiating into blood and blood vessels.

A

Tertiary chorionic villi

23
Q

This the process of gene expression or silencing.

A

DNA methylation

24
Q

Cell lineage studies have shown epiblasts being what?

A

Pluripotent stem cells

25
Q

What genes play a role in the development of handed asymmetry?

A

Nodal genes

26
Q

The notochord is the primary inducer of the overlying ectoderm to form what?

A

The neural plate

27
Q

The process of converting the neural plate into the neural tube (happens in the 4th week)

A

Neuralation

28
Q

The newly formed neural canal communicates with the amniotic cavity through large openings called the…

A

Cranial and caudal neurophores

29
Q

The edges of the neural fold make contact on which day of development?

A

22nd

30
Q

The neurophores close by which day of development?

A

26th

31
Q

Interruption of neural tube closure can lead to which conditions?

A

Spina bifida and anencephaly

32
Q

These cells develop bilaterally along the borders of the neural tube and can differentiate into a number of different cell types.

A

Neural crest cells

33
Q

On each side (paraxial) of the notochord and neural tube in the mesoderm layer thickened areas form. These areas become what?

A

Paraxial mesoderm
Lateral area: Lateral mesoderm
Between the two areas of mesoderm: Intermediate mesoderm

34
Q

These are segmented mesodermal tissue (paraxial) along the neural tube, which gives rise to the vertebral column, voluntary muscle, connective tissue, and skin.

A

Somites

35
Q

This is the process of developing organ systems.

A

Organogenesis

36
Q

The nervous system, neural crest cells, sensory epithelium, epidermis and derivatives, and the pituitary gland are all derivatives of what germ layer?

A

Ectoderm

37
Q

The axial region, paraxial region, intermediate region, and lateral region are all derivatives of what germ layer?

A

Mesoderm

38
Q

The lateral region of mesoderm differentiates into two additional layers of mesoderm. What are they and which germ layer is each one closer to?

A

Splanchnic (closer to the endoderm) and somatic (closer to the ectoderm) mesoderm

39
Q

Blood and blood vessels, heart, lymphatic, cardiac, and visceral muscles as well as the adrenal cortex are all derivatives of what mesodermal layer?

A

Splanchnic mesoderm

40
Q

The skull and muscles of the head are derived from what mesodermal layer?

A

Somatic mesoderm

41
Q

The respiratory system, digestive systems, liver, pancreas, thyroid and parathyroid are all derivatives of what germ layer?

A

Endoderm

42
Q

The study of the fetus and newborn-as patient. From 22 weeks after fertilization viability to 4 weeks after birth.

A

Perinatology

43
Q

Studies concerned with the fetus.

A

Fetology

44
Q

Sampling of amniotic fluid by inserting a hollow needle into the mother’s abdominal and uterine wall.

A

Amniocentesis

45
Q

When is amniocentesis typically performed?

A

After the 14th week of pregnancy

46
Q

What are some indications for the performing of amniocentesis?

A

Late maternal age (38yrs and up)
Previous births with chromosomal abnormalities
Carrier of an inborn metabolic disorder
Family history of defects related to development

47
Q

This tool utilizes pulsed waves that are beamed into the uterus through a transducer on the abdomen.

A

Ultrasound

48
Q

What is the schedule for ultrasounds in the USA?

A

There are usually three scans:
7-8th week to confirm the pregnancy and look for ectopic
18-20th weeks to check for congenital malformations, multiple pregnancies and the position of the placenta
34th week to check the fetal size, growth, and position of the fetus in the uterus.

49
Q

What measurements are taken with ultrasound at the 7-8th week?

A

Crown rump length

50
Q

What measurements are taken with ultrasound at the 18-20th week?

A

Fetal length and biparietal diameter of the fetal skull

51
Q

Fiber optics that are used to scan the entire fetus.

A

Fetoscopy

52
Q

A protective covering of the fetus during the time before birth.

A

Vernix caseosa

53
Q

What are the risks associated with fetoscopy?

A

5-6% of fetal death and spontaneous abortions. As well as radiation exposure-thyroid abnormalities

54
Q

A biopsy of the chorionic villi (mostly trophoblast) that is obtained by inserting a needle into the abdominal and uterine wall.

A

Chorionic villus sampling (CVS)

55
Q

When is chorionic villus sampling typically carried out?

A

8th week of pregnancy

56
Q

What is the major advantage chorionic villus sampling has over amniocentesis?

A

It allows the results of chromosomal analysis to be discovered weeks earlier than amniocentesis.

57
Q

It is a glycoprotein synthesized in the fetal liver, yolk sac, and gut.

A

Alpha Fetoprotein (AFP)

58
Q

Uterine tissue where the placenta is attached

A

Decidua Basalis

59
Q

Uterine endometrium, which covers the blastocyst at the aembryonic end.

A

Decidua Capsularis

60
Q

Uterine endometrium opposite to the sides of implantation.

A

Decidua Parietalis

61
Q

The amniotic cavity grows faster than smooth chorionic membrane and fuse to form what?

A

Amniochorionic membrane (amniotic sac)

62
Q

What membrane ruptures during labor?

A

Amniochorionic membrane (amniotic sac)

63
Q

What is the weight of the placenta?

A

One seventh the weight of the fetus, it is discoid in shape, and 15-20cm–3cm thick

64
Q

In fetal circulation deoxygenated blood is brought to the placenta by what?

A

Umbilical arteries

65
Q

The umbilical arteries form what kind of network in the villi?

A

Arterio-capillary-venous network

66
Q

Do the lungs of the fetus receive oxygen?

A

No

67
Q

Fetal blood is oxygenated through the placenta and passes into what, which carries the blood back to the fetus?

A

Umbilical veins

68
Q

Is the rate of blood flow in the placenta relatively high or low?

A

High

69
Q

A decrease in oxygen due to acute reduction in the maternal blood flow.

A

Fetal hypoxia

70
Q

What are the four layers of the villi?

A

Syntrophoblast, cytotrophoblast, connective tissue layer, and endothelium of fetal capillaries

71
Q

What are the three functions of the placenta?

A

Metabolic (glycogen and cholesterol), transfer (diffusion, facilitated diffusion, active transport, and pinocytosis), and synthesis

72
Q

Fetal movement, proportionate growth, prevention of adherence, cushioning of fetus, supplies nutrients, consistent body temperature, and helps lubricate an dilate the cervis during birth are all functions of what?

A

Amniotic fluid

73
Q

What are two types of abnormal amniotic fluid?

A

Oligohydraminos and polyhydraminos

74
Q

This abnormal amniotic fluid is caused by amniotic fluid leakage, bilateral renal agenesis, polycystic kidneys, and urethral obstruction.

A

Oligohydraminos

75
Q

This abnormal amniotic fluid is caused by esophageal or intestinal atresia and esophageotracheal fistula.

A

Polyhydraminos (excessive amniotic fluid surrounding the fetus)

76
Q

What blood vessels does the umbilical cord contain?

A

One vein and two arteries

77
Q

Nutrient and development of germ cells occurs here. When this structure degenerates it still retains a portion to become vitelline vessels.

A

Secondary umbilical vesicle

78
Q

Vessels of this structure become part of the umbilical vessels-the remainder is a thick band of tissue called the urachus (fetus). In the adult the band of tissue is known as the median umbilical ligament.

A

Allantosis

79
Q

This method is used to assess a newborn quickly, is repeatable, and measures vital signs at birth.

A

APGAR score

80
Q

What are the five criteria for an APGAR score?

A

Appearance (skin color), pulse (heart rate), grimace (reflex irritability), activity (muscle tone), and respiration

81
Q

What is a normal APGAR score?

A

7-10, 4-6 is considered fairly low, and 3 and below is considered to be critically low.

82
Q

Babies mouth or chin is stroked. The baby will turn their head and open mouth to “root” in the direction of stroking. What primitive reflex is this?

A

Root reflex

83
Q

When the roof of the baby’s mouth is touched and the baby begins to suck. This reflex does not begin until the 32nd week of development. What is it?

A

Suck reflex

84
Q

When a baby is startled or a loud sound is made the baby throws back their head, extends out the arms and legs, then pulls their arms and legs back into their body. What is this reflex?

A

Moro- or startle reflex

85
Q

When a baby’s head is turned to one side the arm on the side of the turned head will stretch out and the opposite arm will bend at the elbow. What reflex is this?

A

Tonic neck reflex or Fencing

86
Q

Touching the baby’s palm will have the baby close their fingers around the object. What reflex is this?

A

Grasp reflex

87
Q

When the sole of the foot is stroked the big toe bends back to the top of the foot and the other toes splay out. What reflex is this?

A

Babinski’s reflex

88
Q

The baby appears to be walking when held with their feet touching a solid surface. What reflex is this?

A

Stepping reflex

89
Q

The baby is on their stomach. Stroke their neck to the middle or lower back, the baby will curve their back toward the side that is being stroked. What reflex is this?

A

Gallant reflex

90
Q

This is a type of tumor that derives from pluripotent germ cells. They can start from cells in the testes, ovaries, or sacrum.

A

Teratoma dermoid cyst

91
Q

Some teratoma secrete this hormone?

A

Human gonadotropin (HCG)

92
Q

What are the three types of teratoma?

A

Mature (benign), immature (malignant), and monodermal (highly specialized)

93
Q

Malignant teratoma contain what embryonic layers? Who are they most prevalent in?

A

Contain ectoderm, mesoderm, and endoderm. Most prevalent in men (symptoms commonly found in the chest)

94
Q

This is a rare condition where a malformed parasitic twin is found inside the body of the partner.

A

Fetus in fetu

95
Q

In order to be called a true fetus in fetu what must it demonstrate?

A

Organogenesis

96
Q

What is the most common type of Chiari?

A

Type I

97
Q

What are the symptoms of Chiari?

A

Headaches, coughing, sneezing, straining, neck pain running down the shoulders, unsteady gait, poor fine motor skills, and numbness or tingling of hands and feet.

98
Q

When does type I chiari usually occur?

A

It usually goes unnoticed until trauma or a person matures
Adolescence or adulthood
As the brain gets bigger symptoms develop
Usually late teens, early adulthood

99
Q

This condition is characterized by cavities or cysts in the spinal cord. These cysts can be fluid filled and the spinal cord can become compromised.

A

Syringomyelia

100
Q

What is the treatment for syringomyelia?

A

Draining of the cyst or surgery

101
Q

This type of chiari is characterized by a great amount of brain tissue protruding into the upper spinal column.

A

Type II

102
Q

This type of chiari is characterized by the back of the brain protruding out of an opening (undeveloped) part of the skull.

A

Type III

103
Q

This type of chiari is characterized by the back of the brain failing to develop properly.

A

Type IV

104
Q

What are the causes of chiari?

A

Exposure to toxic chemicals, prescription or illegal drugs or alcohol, poor nutrition, and infection

105
Q

This is a malformation of the brain that consists of a downward displacement of the cerebellar tonsils through the foramen magnum.

A

Chiari malformation