Embryogenesis and Fetal Period

Question 1

neurulation

Answer 1

ectoderm thickens and becomes known as the neural place

Question 2

what happens on day 22 in reference to the neural plate

Answer 2

it begins to fold inward and makes contact with four occpital somites and the first cervical somites

Question 3

what day does the cranial neuropore close

Answer 3

24 or 25

Question 4

what day does the caudal neuropore close

Answer 4

26 or 27

Question 5

the fusion of the neural folds results in the formation of what ?

Answer 5

neural tube

Question 6

neural crest cells

Answer 6

really important, lose attachment to neural tube and form a lot of things

Question 7

what are some examples of neural crest derivatives

Answer 7

parasympathetic ganglia of 3,7, 9 and 10, sensory ganglia of central nervous sytem of 5, 7, 9 and 10 and the autonomic doral root ganglia

Question 8

surface ectoderm gives rise to what ?

Answer 8

epidermis, hair, nails, cutaneous, mamary glands, anterior pituitary gland, enamel of teeth, internal ear, and lens of eye

Question 9

mesoderm immediately laterally to the notochord form cylindrical bodies called ___________

Answer 9

paraxial mesoderm

Question 10

mesoderm just laterally to the notochord forms_________

Answer 10

intermediate mesoderm

Question 11

futherest lateral to the notochord forms _____-

Answer 11

lateral plate mesoderm

Question 12

paraxial mesoder

Answer 12

axial skeleton, volutary musclulatur and part of the dermis

Question 13

intermediate mesoderm

Answer 13

form the urinary system and parts of the genital system

Question 14

lateral plate mesoderm

Answer 14

will split into two layers splachnic mesoderm (associated with endoderm) and somatopleuric mesoderm (associated with the ectoderm)

Question 15

the paraxial mesoderm helps form the first ________-

Answer 15

somite on day 20

Question 16

how many pairs of somites are there ?

Answer 16

37 pairs

Question 17

the endoderm of the embryo contributes to what structure ______________

Answer 17

yolk sac

Question 18

endoderm derivatives

Answer 18

epithelial lining of GI tract, allantois, epithelium of repiratory tract, bladder, urethra, tympanic cavity and auditory tube, parenchyma of thyroid, parathyroid, liver and pancreas, stroma cells of the tonsils and the thymus

Question 19

when is the fetal period

Answer 19

9th week til birth

Question 20

characteristics of weeks 9-12

Answer 20

liver is major site of erythropoeisis, and the external genitals can be distinguished male or female

Question 21

weeks 13-16

Answer 21

sites of ossification are evident, eye movements and the eyes are facing forward

Question 22

weeks 17-20

Answer 22

primary ovarian follicles are formed and testes are descending

Question 23

weeks 21-25

Answer 23

period of weight gain, blink and startle reflexes, surfactant is beginning to be secreted into the lungs

Question 24

weeks 26-29

Answer 24

lungs are capable of breathig, CNS is capable of breathing and body temperature, spleen is still making blood cells but by 28 weeks blood formation shifts to the bone marrow

Question 25

weeks 30-34

Answer 25

pupillary light reflex is present, fat is still accumulating

Question 26

weeks 35-38

Answer 26

finish period involves final preparations of tissues important to the outside world

Question 27

for the first 12 weeks of developent what is the major blood producing organ

Answer 27

yolk sac

Question 28

for weeks 12-30 what organ is the major blood producing organ and weeks 12-24

Answer 28

liver, spleen

Question 29

by week 30 what is the major hemopoietic organ

Answer 29

bone marrow

Question 30

what is amniocentesis ?

Answer 30

sampling of the amnioc fluid to test for genetic disorders (must pass through chorion and amnion to get the sample)

Question 31

by the 4th week the somites begin to differentiate into ______________ and ___________-

Answer 31

sclerotome and dermomyotome

Question 32

hemangioblast

Answer 32

give rise to blood vessels

Question 33

vasculogenesis

Answer 33

formation of blood islands, denovo vessels

Question 34

angiogenesis

Answer 34

sprouting from existing vessels

Question 35

hemangiomas

Answer 35

tumor like collections of blood vessels typically on the face

Question 36

epithlium derived from the mesoderm is

Answer 36

vascular endothelium

Question 37

epithelium derived from the endoderm is

Answer 37

epithelium of structures derived from yolk sac (gut and airway)

Question 38

epithlium derived from the ectoderm

Answer 38

epidermis and ependyma

Question 39

benign tumors of mesoderm epithelium are

Answer 39

angiomas

Question 40

malignant tumors of mesoderm epithelium are

Answer 40

sarcomas

Question 41

benign tumors of endoderm epithelium are

Answer 41

pailoma or adenomas

Question 42

malignant tumors of endoderm epithelium are

Answer 42

carcinomas

Question 43

benign tumors of ectoderm epithelium are

Answer 43

papiloma and ademoas

Question 44

malignant tumors of ectoderm epithelium are

Answer 44

carcinomas

Question 45

connective tissue is derived from ?

Answer 45

mesoderm for torso and limps and neuroectoderm (head)

Question 46

benign tumors of connective tissue mesoderm

Answer 46

fibroma, lipoma, chondroma, osteoma

Question 47

malignanty tumors of connective tissue medoderm

Answer 47

sarcomas

Question 48

benign tumors of muscle mesoderm

Answer 48

myomas

Question 49

malignant tumors of muscle mesoderm

Answer 49

myosarcomas

Question 50

what are the two types of paraxial mesoderm

Answer 50

sclerotome and dermomyotome

Question 51

what does the sclerotome give rise to

Answer 51

skeleton and cartilage

Question 52

what does the dermomyotome give rise to

Answer 52

skeletal muscles, dermis and connective tissues

Question 53

expected date of confinement ( EDC)

Answer 53

measures corwn rump length, head measurements and femur length to determine age

Question 54

gestation age

Answer 54

age from last menstruation!

Question 55

last nomrla menstrual period

Answer 55

with this gestation takes 40 week

Question 56

actual date of fertilization

Answer 56

with this measure it takes 38 weeks

Question 57

what is the first trimester

Answer 57

all major systems are developed

Question 58

second trimester

Answer 58

external anatomy, many birth defects can be detected

Question 59

third trimester

Answer 59

fetus becomes viable

Question 60

if alpha fetoprotein is elevated what happens

Answer 60

detects of embryonic body wall

Question 61

if alpha fetoprotein is depressed what can result

Answer 61

downs syndrome and trisomy 18

Question 62

surface ectoderm gives rise to

Answer 62

epidermis, hair,cutaneous and mammary glands, anterior pituitary gland, enamel of teeth, internal ear, and lens of the eye

Question 63

what does paraxial mesoderm give rise to

Answer 63

sclerotome which gives rise to skeleton and cartilage | dermomyotome which gives rise to skeletal muscles, dermis and connective tissue

Question 64

what does intermediate mesoderm give rise to

Answer 64

urogenital system and contributions to the reproductive system

Question 65

what does the lateral plate mesoderm give rise to

Answer 65

somatic(parietal) layer gives rise to connective tissue of limbs and serious membranes splanchnic (visceral) layer gives rise to connective tissue, smooth muscle of vercera, serious membranes, primordial heart, blood, spleen, and suprarenal cortex

Question 66

what does the endoderm give rise to

Answer 66

epithelium of the GI tract, liver, pancrease, liver, urachus, trachea, bronchi, longs, pharynyx, and thyroid

Question 67

what does the neural ectoderm give rise to

Answer 67

``` neural tube (CNS, retina, pineal gland, and posterior pituitary) neural crest (all ganglia) ```

Question 68

the myotome splits into what

Answer 68

epaxial (intrinsic back muscleS) and hypomeres (hypaxial)

Question 69

epithelium is derived from what layers

Answer 69

all three

Question 70

connective tissue is derived from what

Answer 70

neuroectoderm and mesoderm

Question 71

muscle is derived from

Answer 71

mesoderm

Question 72

nerve is derived from

Answer 72

neuroectoderm