Embryology: Conception to Zygote Formation Flashcards Preview

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Flashcards in Embryology: Conception to Zygote Formation Deck (84)
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1
Q

Phase of reproduction where two haploid sex cells fuse What do they form?

A

Fertilization

Zygote

2
Q

The vaginal canal is BASIC/ACIDIC

Prostate gland produces alkanine or acidic sustenances for the semen to protect it?

A

Acidic

Alkaline

3
Q

In addition to mature, fully motile sperm and unobstructed female reproductive tract, 2 other things are required for successful fertilization

A

Capacitation

Acrosome Reaction

4
Q

This is the process in fertilization tha ttallows sperm to become mobile enough to attach to cells on the oocyte

It happens in where?

A

Capacitation

Uterine Tube

5
Q

This is a group of cells surrounding the oocyte, plays a role in the binding of sperm (it’s the epithelium it binds to)

A

Corona Radiata

6
Q

Before sperm can bind to the corona radiata, the top layers of the _____ of sperm are taken away via the sperm attaching to the…

A

Epididymis of sperm

Attaches to the epithelium of the fallopian tube

7
Q

During fertilization, after the sperm binds to the epithelium of the fallopian tube and sheds the epididymis, what effect does it have on the sperm?

A

The cell becomes highly motile, allowing it to bind to cells on the oocyte

8
Q

What adhesion molecules play a role in capacitation?

A

E-Cadherins and integrins

9
Q

This covers the sperm, and when it breaks down, it releases enzymes for breakdown of ____ allowing the sperm to fuse with enzymes of the egg

This whole process is called the

A

Acrosome Cap

Zonapellucida, ECM

Acrosome reaction

10
Q

This part of the oocyte hydrolyzes sperm receptors, inactivating so no other sperm can penetrate once one already has

A

Cortical Granules

11
Q

This is the word used to describe a cell that can differentiate into any cell or extraembryonic structure in our body

A

Totipotent

12
Q

This is the term used to describe a cell that is capable of differentiating into several cell types, or any embryonic structure

A

Pluripotent

13
Q

This is the period that begins with 24 hours after fertilization, the newly created diploid cell begins dividing

A

Cleavage

14
Q

This forms 3-4 days after fertilization, it is a solid ball of cells

A

Morula

15
Q

This forms 5-6 days after fertilization, it has an inner cell mass, tropho blast, and a cavity

A

Blastocyst

16
Q

In the blastocyst, this is the outer ring of cells

It forms the _____ contribution to the placenta

A

Trophoblast

Embryonic

17
Q

This is the innter cluster of cells that forms the embryo in the blastocyst

A

Embryoblast

18
Q

Are cells totipotent or pluripotent in the embryoblast?

A

Pluripotent

19
Q

This is the fluid filled space in the blastocyst that lies between trophoblast and embryoblast

A

Blastocyst Cavity

20
Q

During week 1 of reproduction, the blastocyst implants into the functional layer of the ________

A

Endometrium

21
Q

What adhesion molecules are important for binding of blastocyst to the uterine wall?

A

Integrins

22
Q

Once the blastocyst is bound to the uterine wall, what divides to further penetrate into the endometrial tissue?

A

Trophoblast

23
Q

During weeks 1-2, the trophoblast differentiates into 2 different layers..

A

Cytotrophoblast and syncytiotrophoblast

24
Q

During weeks 1-2, this is the inner layer of the trophoblast in a developing embryo

A

Cytotrophoblast

25
Q

During weeks 1-2 of reproduction, this is the epithelial covering of the highly vascular embryonic placental villi

A

Syncytiotriphoblast

26
Q

During weeks 1-2, lakes of blood surround the ___________, allow it to continue to grow and fuse even furtehr into maternal embryonic tissues

A

Syncytiotrophoblast

27
Q

This is the hormone secreted by the syncytiotrophoblast until the maternal tissues produce enough progesterone

A

HCG

28
Q

During week 2, the embryoblast (bilaminar germ dis) starts epithelizing into…

A

Epiblast and Hypoblast

29
Q

During week 2, epiblast cells differentiate to create the…

Note: Epiblast later becomes human tissues

A

Amniotic Cavity

30
Q

During week two, the hypoblast also moves out like the epiblast, and line the cytotrophoblast to form the….

A

Yolk Sac

31
Q

During week 2 (10-13 days), the hypoblast tissue continues to move out and create this connective tissue, between the hypoblast and cytotrophoblast

A

Mesoderm

32
Q

During week 2 (10-13 days) this is generated from tiny spaces in the mesoderm

A

Chorionic Cavity

33
Q

During 12-13 days, the yolk sac pinches off, becomes ______

The epiblast cells create the ________

The ______ surrounds everything, but there is a huge cavity

The amniotic cavity starts to become _______

A

Secondary Yolk sac

Amniotic Membrane

Extraembryonic mesoderm, (connective tissue)

Human tissues

34
Q

So in sum of second week…..

A
35
Q

During week three, the most important event in your life occurs

A

Gastrulation

36
Q

What appears during the third week?

On what end of the embryo do cells cluster within the amniotic cavity to form it?

A

Primitive streak

Caudal

37
Q

Why is the primitive streak important for gastrulation?

A

It establishes axes (caudal/cranial) (left and right) (anterior and posterior

38
Q

To form the primitive streak, what type of cells migrate at the midline?

A

Epiblast

39
Q

After establishment of the primitive streak within the amniotic cavity, which is ventral, the amniotic cavity or the yolk sac?

A

Yolk sac is ventral, amniotic cavity is dorsal

40
Q

When epiblast cells migrate to the primitive streak, the cell detach, invaginate and replace the _______ to form the ________

Further migrating cells differentiate and form the

A

Hypoblast to form the endoderm

Mesoderm

41
Q

When epiblast cells migrate to the primitive streak, what occurs

Why?

A

Epithelio-mesenchyme transition

Mesenchyme can move, lots of fluid allowing it to

42
Q

During the epithelio-mesenchymal transition, the remaining epiblast cells that didn’t migrate to form the

A

Ectoderm

43
Q

Once the 3 germ layers are formed during gastrulation, the cells are no longer….

But they are..

A

Pluripotent

Multipotent

44
Q

At this point in the picture, what happens to the cells on top of the epiblast?

At this point in the picture, what happens to the cells that remain of the epiblast?

A

Cells on top detach, migrate, and form the mesenchyme

The remaining cells form the ectoderm

45
Q

The yellow that is directly under the mesoderm in the picture is from what? Is it from the hypoblast

So then where is the hypoblast?

A

No, it’s from the cells that migrated through the primitive streak

It’s the part that doesn’t directly underlie the mesoderm

46
Q

What does the migrating mesoderm (the red in the picture) become?

A

Connective Tissue

47
Q

The black boundary in the middle is also formed from migrating mesoderm, what structure does it form?

A

The notochord

48
Q

In the picture, the mesoderm that migrates along either side of the notochord is called the…

A

Paraxial Mesoderm

49
Q

In the picture below, what are I and S? Also note the location of the lateral plate mesoderm

Also, what is the space above the blue line?

A
  1. I is the lateral plate mesoderm
  2. S is the paraxial mesoderm
  3. The space is the amniotic cavity
50
Q

What is the blue and the yellow in the picture below?

A
  1. Blue is ectoderm
  2. Yellow is endoderm
51
Q

What does the intermediate mesoderm form most of?

A

The urinary and reproductive system

52
Q

What is the name for the space that exists because of the split in the lateral plate mesoderm?

A

Intraembryonic Coelom

53
Q

What is the function/purpose of the space between the blue (ectoderm) and the outer intermediate mesoderm?

A

Supports the body wall with muscle and connective tissue

54
Q

What does the space between the mesoderms, formed by the lateral plate (the intraembryonic coelom) become?

A

Abdominal Cavity

55
Q

What does the space between the endoderm (yellow) become?

A

Gut Tube

56
Q

This is the term describing the part of the mesoderm that becomes the body wall

A

Somatopleure

57
Q

This is the term for the mesoderm that lines the outer part of the gut tube

A

Splanchopleure

58
Q

As seen in the picture below, the mesoderm folds back over the ectoderm and endoderm. What is the mesoderm on top of the structure in the picture?

What is the mesoderm on bottom of the picture?

A

Somatopleure

Splachnopleure

59
Q

Identify the colored areas in this picture

A
60
Q

Which contributes most to the development of the notchord, ectoderm, mesoderm, or endoderm?

A

Mesoderm

61
Q

The notochord defines the ___ axis of the embryo

It induces the development of these two things

A
  1. Defines the primordial axis of embryo
  2. Induces the development of the neural plate
  3. Induces development of axial skeleton
62
Q

What forms around the notochord?

What eventually happens to the notochord?

A

The vertebral column

It regresses and mostly disappears (except for intervertebral discs)

63
Q

The notochord loses its epithelial connection and becomes attached to the..

It then loses it’s epithelial connections once more and what happens ?

A

Endoderm

Cells at the end compact and it becomes a rod (see picture)

64
Q

The paraxial mesoderm forms the….

A

Somites

65
Q
  1. These are the striated muscles of the body wall
  2. They divide into two parts
A

Myotomes

Epimere and hypomere

66
Q
  1. During segmentation, what folds in and creates neural tube?
  2. What is within the neural tube (ventral to neural tube here)
A
  1. Ectoderm
  2. Notochord (ventral to NT here)
67
Q

The somites divide into three parts, what are they?

A
  1. Scleratomes
  2. Myotome
  3. Dermatome
68
Q

Which aspect of the somite becomes cartitlage, supportive tissues, vertebrae and ribs

A

Scleratomes

69
Q

Which part of the somite forms muscles of body wall and limbs (trapezius, splenius, lats)

A

Myotomes

70
Q
  1. The myotome divides into two parts, called…
  2. This is the dorsal part of the myotome
  3. This is the ventral part of the myotome
A
  1. Epimere and Hypomere
  2. Epimere
  3. Hypomere
71
Q

This part of the myotome gives rise to the deep back muscles

A

Epimere

72
Q

This part of the myotome forms the ventral muscles and superficial back

A

Hypomere

73
Q

This part of the somite becomes the dermis

A

Dermatomes

74
Q

Identify the lines in this picture

A
75
Q

To form the dermis, the dermatomes join with what?

A

Somatopleure

76
Q

Identify the lines in this picture

A
77
Q

Scleretomes on either side grow towards one another, fuse, surround neural tube, form the…

A

Spinal Vertebrae

78
Q

These divide in half, top and bottoms of different ones fuse with one another, creating ones

Why is this beneficial?

A

Somites

It allows muscles to span vertebrae, creating movement

Also creates space for spinal nerves to travel

79
Q

During neuration, as shown in the picture, what structure is folding out?

What does it form?

A

Ectoderm

Neural plate

80
Q

During neurulation, what forms due to the rising of the lateral plate? The cells get thicker on at basal end but thinner at apical end

A

Neural groove and neural fold

81
Q

At this point in the picture, the ectoderm is well positioned to form the ___ but not the _____

A
  1. Skin
  2. Brain
82
Q
  1. When the neural folds reach eachother, where does fusion begin?
  2. What does this fold and fusion eventually form?
A
  1. In the middle, the fuses away from middle in cranial and caudal direction
  2. Neural Tube
83
Q

What does the neural tube form?

A

CNS and somatic efferent (motor) neurons

84
Q

Within the neural fold, these detach, migrate and become other nervous system processes (afferent neurons, dorsal root ganglia, much of ANS and ganglia, glial cells, many cells in endocrine and other body systems)

A

Neural crest cells