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NPLEX - Anatomy > Embryology > Flashcards

Flashcards in Embryology Deck (63)
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1
Q

Which of the three germ layers will give rise to connective tissue?

A

mesoderm

2
Q

Name the cell mass that form the floor of the amniotic cavity.

A

epiblast

3
Q

The neurohypophysis, CNS neurons, oligodendrocytes, astrocytes, and pineal are derived from which primitive layer?

A

neuroectoderm

4
Q

The ANS, chromaffin cells of adrenal medulla, parafollicular cells, and laryngeal cartilage are derived from which primitive layer?

A

neural crest

5
Q

Which of the three germ layers will give rise to the epithelial lining of the respiratory tract?

A

endoderm

6
Q

Trace the seven steps of spermiogenesis, from spermatogonia to spermatozoa.

A

spermatogonia (46xy), primary spermatocyte, first meiotic division, 2 secondary spermatocytes (one 23x, one 23y), second meiotic division, 4 spermatids (two 23x, two 23y), 4 spermatozoa (two 23x, two 23y)

7
Q

Which structure contains a fluid-filled cavity that separates the blastomere into two distinct parts?

A

blastula

8
Q

Which of the three germ layers will give rise to the nervous system?

A

ectoderm

9
Q

Name the precursor of the ectoderm.

A

epiblast

10
Q

Which structure contains 12-15 blastomeres?

A

morula

11
Q

What is the postnatal derivative of the notochord?

A

nucleus pulposus of the intervertebral disk

12
Q

Which germ layers arise from the primitive streak?

A

intra-embryonic mesoderm and endoderm

13
Q

Where does fetal erythropoiesis occur in the 3rd to 8th weeks?

A

yolk sac

14
Q

How many spermatids are produced from one spermatogonia?

A

4

15
Q

What is the genetic complement of a spermatogonia cell?

A

46 XY

16
Q

Which monosaccharide is the main energy supply for sperm?

A

fructose

17
Q

Which structure induces the ectoderm to form neuroectoderm (neural plate)?

A

notochord

18
Q

Muscles, bone, CV structures, lymphatics, blood, spleen, and adrenal cortex are derived from which primitive layer?

A

mesoderm

19
Q

The bilaminar disk is formed within which week?

A

week 2

20
Q

What is the function of ductus arteriosus in fetal circulation?

A

deoxygenated blood from SVC is expelled into the pulmonary artery and ductus arteriosus to the lower body of the fetus.

21
Q

What is the spermatic complement of a spermatocyte that has undergone the first meiotic division?

A

one 23x and one 23y (secondary spermatocytes)

22
Q

Branchial pouches are derived from which primitive layer?

A

endoderm

23
Q

Which structures does the truncus arteriosus gives rise to?

A

ascending aorta and pulmonary trunk

24
Q

What does the embryonic ductus venosus become after birth?

A

ligamentum venosum

25
Q

Branchial clefts are derived from which primitive layer?

A

ectoderm

26
Q

What is the function of foramen ovale in fetal circulation?

A

most oxygenated blood reaching the heart via the IVC is diverted through the foramen ovale and pumped out of the aorta to the head.

27
Q

What kind of blood (oxygenated/deoxygenated) do the umbilical arteries carry?

A

deoxygenated blood from fetus to the placenta

28
Q

The gut tube epithelium and derivatives (lungs, liver, pancreas, thymus, thyroid, parathyroid) are derived from which primitive layer?

A

endoderm

29
Q

Days 15-28 make up which phase of the menstrual cycle?

A

luteal (secretory) phase

30
Q

Which structure closes at birth after the infant takes its first breath?

A

ductus arteriosus

31
Q

What kind of blood (oxygenated/deoxygenated) is carried by the umbilical vein?

A

oxygenated blood from placenta to the fetus

32
Q

Name the two main components of the placenta in the second week.

A

cytotrophoblast and syncytiotrophoblast

33
Q

Name the stages of embryogenesis from day zero to implantation at the end of week one.

A

fertilization (day 0), zygote (day 2), morula (day 3), blastocyst (day 5), implantation (day 6)

34
Q

Days 1-4 in the menstrual cycle make up which phase?

A

menstrual phase

35
Q

Monozygotic twins share ___ amniotic sacs, ___ placentas, and ___ chorions.

A

2, 1, 1

36
Q

Which of the three germ layers will give rise to blood vessels?

A

mesoderm

37
Q

Which of the three germ layers will give rise to the CV system?

A

mesoderm

38
Q

How many cavities in the second week of fetal development and what are they?

A

amniotic cavity and yolk sac

39
Q

Dizygotic (fraternal) twins share ___ amniotic sacs, ___ placentas, and ___ chorions

A

2, 2, 2

40
Q

Name the process whereby immature spermatids become spermatozoa.

A

spermiogenesis

41
Q

The adenohypophysis, lens of eye, epithelial linings, and epidermis are derived from which primitive germ layer?

A

surface ectoderm

42
Q

When do primary oocytes begin and complete meiosis I?

A

being during fetal life, complete just prior to ovulation

43
Q

Which of the three germ layers will give rise to glands that open into the GI tract?

A

endoderm

44
Q

Branchial arches are derived from which primitive layer?

A

mesoderm and neural crests

45
Q

What does the embryonic foramen ovale become after birth?

A

fossa ovalis

46
Q

How many germ layers are present in the third week and what are they?

A

ectoderm, mesoderm, endoderm

47
Q

Trace the five steps of oogenesis from primary oocyte to mature oocyte.

A

primary oocyte in primary follicle, first meiotic division, secondary oocyte (23x) in mature follicle and first polar body, second meiotic division, mature oocyte (23x) and second polar body (23x)

48
Q

Which structure does the right common cardinal vein and right anterior cardinal vein gives rise to?

A

superior vena cava

49
Q

Name the cell mass that forms the roof of the exocoelemic cavity.

A

hypoblast

50
Q

Which of the three germ layers will give rise to glandular cells of the liver and pancreas?

A

endoderm

51
Q

Which of the three germ layers will give rise to the lining of the GI tract?

A

endoderm

52
Q

Days 4-14 make up which phase of the menstrual cycle?

A

follicular (proliferative) phase

53
Q

Where does fetal erythropoiesis occur during the 9th to 28th weeks?

A

spleen

54
Q

Which of the three germ layers will give rise to blood cells?

A

mesoderm

55
Q

Name the process that converts a bilaminar embryonic disc into a trilaminar embryonic disc.

A

gastrulation

56
Q

Where does fetal erythropoiesis occur during the 6th to 30th weeks?

A

liver

57
Q

Where specifically does spermatogenesis occur?

A

seminiferous tubules

58
Q

When does the heart begin to beat and upper and lower limb buds begin to form?

A

week 4

59
Q

What does the embryonic ductus arteriosus become after birth?

A

ligamentum arteriosum

60
Q

What is the ploidy of a zygote?

A

diploid

61
Q

Implantation of blastocyst is present in which week?

A

1

62
Q

How many umbilical veins are there?

A

1

63
Q

What phase is meiosis II arrested in during oogenesis?

A

meiosis II is arrested in metaphase until fertilization