Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IMS > Embryology 3: Derivative of germ layers > Flashcards

Embryology 3: Derivative of germ layers Flashcards

1
Q

What are the cells of the bilaminar

A
  • hypoblast

- epiblast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens in gastrulation

A

Bilaminar —> trilaminar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When does gastrulation commence

A
  • week 3

- as primitive streak (PS) is formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is established by the time gastrulation commences

A
  • cranial/ caudal

- right/left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the name of the condition where the R to L asymmetry is reversed

A

Inversus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How common is inversus

A

1 in 10000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How harmful is complete situs inversus

A

Often harmless

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How common is Kartagene syndrome

A

20% of patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Give example of partial situs inversus

A

Dextrocardia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is definitive endoderm formed

A
  • epiblast cells move towards PS
  • detach from epiblast
  • insert into hypoblast —> replace hypoblast cells
  • new cells formed —> definitive endoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is mesoderm formed

A
  • epiblast cells continue moving down PS

- middle layer between epiblast & definitive endoderm —> mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is ectoderm formed

A
  • remaining epiblast become ectoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What completes gastrulation

A

Formation of ectoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does trilaminar embryonic disc contain

A
  • ectoderm
  • mesoderm
  • endoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the two types of mesoderm that are continuous with each other

A

Intraembryonic & extraembryonic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where does every body system come from

A

The 3 germ layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does Ectoderm develop into

A
  • CNS
  • PNS
  • Epidermis of skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does Mesoderm develop into (Day 16)

A
  • Skeletal & smooth muscles
  • Heart
  • Urinary system
  • Reproductive tract
  • Kidneys
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does Endoderm develop into (Day 14-15)

A
  • Epithelial lining of GI tract
  • Glands
  • Bladder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the three levels of mesoderm organisations

A
  • Paraxial (close to middle)
  • Intermediate
  • Lateral plate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does paraxial mesoderm form

A
  • majority of skeleton
  • skeletal muscles
  • dermis of skin
22
Q

What does intermediate mesoderm

A
  • glands
  • internal reproductive tracts
  • kidneys
23
Q

What does lateral plate mesoderm form

A
  • lining of body cavities
24
Q

Which cavity does the primitive streak form

A

Amniotic cavity

25
Q

When do somites form

A

Day 20 post fertilisation

26
Q

How do somites form

A

Paraxial mesoderm starts dividing into blocks

27
Q

Where do somites begin

A 
Cranial region 
|
|
|
|
|
Caudal region
28
Q

How many somites are formed

A

42-44 pairs

29
Q

What is the rate of somite formation

A

3 or 4 pair per day

30
Q

Why is somites formation’s predictability useful

A

Estimate embryo’ s age

31
Q

Name two disorders of abnormal gastrulation

A
  • Sirenomelia - Mermaid syndrome

- Sacrococcygeal Teratoma - SCT

32
Q

What are the causes of sirenomelia

A
  • not enough migration of epiblast cells

- insufficient mesoderm is formed in caudal region

33
Q

What does Sirenomelia cause

A
  • abnormalities of urogenital system

- lower limbs

34
Q

What causes SCT

A

Remnants of primitive streak

35
Q

What is the most common tumour in newborn babies

A

SCT - 1 in 35-40,000

36
Q

How common is SCT in females

A

80%

37
Q

What does the primitive node form whilst the primitive streak is regressing

A

Notochordal process

38
Q

How is notochordal plate formed

A

Notochordal process fusing with endoderm

39
Q

How is notochord formed

A
  • Notochordal plate separates from endoderm

- fuses

40
Q

What is the first event in the development of the CNS

A

Initiating neurulation

41
Q

What does notochord initiate

A
  • nurulation

- formation of vertebrae from somites

42
Q

How is the induction of nurualation done

A
  • initiated by signals from notochord
  • overlying ectoderm thickens
  • Nepal plate formed
43
Q

What does notochord induce somites into

A
  • scleromote
  • myotome
  • dermatome
44
Q

What does sclerotium develop into

A
  • bone

- cartilage

45
Q

What does myotome develop into

A

Skeletal muscle

46
Q

What does dermatome develop into

A

Dermis

47
Q

How do sclerotium cells form the vertebrae

A
  • surround notochord —> vertebral body

- surround neural tube —> vertebral arch

48
Q

What is the fate of notochord

A
  • majority degenerates

- remnants persist as nucleus pulposus of intervertebral discs

49
Q

What can abnormal induction of sclerotomes cause

A

Spinal defects

50
Q

Give examples of spinal defects

A
  • A. Spina bifida
  • B. Meningocele
  • C. Myelomeningocele

IMS (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions