Embryo & Genetics Flashcards
1
Q
peanut esr
small lower
jaw
fish mouth
branchial arch disorder
CHL
A
treacher collins
2
Q
small lower jaw
tongue further back
cleft palate
CHL
branchial arch syndrome
A
sticklers
3
Q
underdevelopment of middle of the face & small lower jaw
near sightedness
CHL
joint problems (arthritis)
branchial arc syndrome
A
Pierre robbins
4
Q
trigeminal nerve
tensor tympani
malleus & incus
all form from this arch
A
1st branchial arch (mandibular)
5
Q
facial n
stapedius muscle
stapes
all form from this arch
A
2nd branchial arch (hyoid)
6
Q
germ cells develop
A
pre embryonic
7
Q
all organs develop from germ layers
A
embryonic
8
Q
maturing of the organs
A
fetal
9
Q
1/2nd arches invaginate at week 6, creates canal and it develops until week 26
A
EAC
10
Q
(week 8-21) tubotympanic recess from 1st pouch, the ossicles develop outside of it and then month 8, they get sucked into the cavity
A
middle ear
11
Q
3 hillocks between ½ arches, week 5 they appear, week 7 they fuse, week 30 complete formation (1st cleft has anterior half of it, 2nd cleft has posterior half of it)
A
pinna
12
Q
22 days gestation, ectodermal placode thickens and invaginates to form otic pit, located dorsal to 2nd arch at day 26, then pit splits into ventral and dorsal part at day 28
A
inner ear
13
Q
week 6, saccule pole extends. Week 8, it has done 2.5 turns, done developing by month 5
A
cochlea
14
Q
week 6 SCC’s are flat pockets as extension of the utricle, week 9 mesenchyme hardens to form cartilage around the system (later turns to bone)
A
vestibular sytem
15
Q
what does the cochlea develop from
A
sacculewhat d
16
Q
what does the vestibular system develop from
A
utricle
17
Q
centrioles go to poles
A
prephase
18
Q
chromies line in the center
A
metaphase
19
Q
chromies break at centromeres,
A
anaphase
20
Q
new nuclear membrane forms at poles
A
telophase
21
Q
replaces dead cells, somatic cells, ends with 2 identical daughter cells with a diploid set of 46 chromosomes, ensures identical daughter cells, 1 division cycle
A
mitosis
22
Q
produces gametes, germ cells, ends with 4 different daughter cells with a haploid set of 23 chromosomes, ensures variation of daughter cells, 2 division cycles
A
meiosis
23
Q
Sugar + Base + Phosphate
A
nucleotide
24
Q
how do the bases pair
A
AT
GC
25
UAA, UAG,UGA
3 stop codons
26
AUG (methionine)
start codon
27
Double strand, has thymine, one less oxygen (deoxy), maintains proteins (encodes info)
dna
28
Single strand, has uracil, enough oxygen (ribose), carries protein (decoding info)
rna
29
DNA to RNA (in nucleus
transcription
30
mRNA to Protein (in cytoplasm)
translation
31
An environmentally caused trait that mimics a genetically determined trait
phenocopy
32
Thalidomide exposure is an example
phenocopy
33
The diverse effects of one gene or gene pair on several organ systems and functions resulting in multiple phenotypic effects in the body
Marfan's
pleitropy
34
Only one chromosome of the chromosome pair is present rather than the usual two
Males are this because they have XY
hemizygous
35
causes 50-80% of all AR genetic HL
connexin
36
Increased K+ transport in the endolymph or increased endolymph production
Meniere's disease
endolymphatic hydrops
37
Decreased K+ transport in the endolymph or decreased endolymph production
Connexin 26 HL
endolymphatic xerosis
38
hexagonal array of proteins in membrane of each cell that line up to the corresponding connexin proteins of the adjacent cell
connexin
39
35delG
connexin
40
Prior to or at conception, a pair of 21 chromosomes in either the sperm or the egg fails to separate (nondisjunction)
As the embryo develops, the extra chromosome is replicated in every cell of the body and accounts for an extra chromosome 21
the failure of the chromosomes to separate, which produces daughter cells with abnormal numbers of chromosomes
nondysjunction
41
Centromeres break and the long arms fuse → short arms fuse to form a new chromosome → new small chromosomes go away after few cell cycles → end result has new balanced chromosome with all the genetic information needed
robertsonian translocation
42
Occurs in nondisjunction of chromosome 21 takes place in one but NOT ALL of the initial cell divisions after fertilization
Some cells contain 46 chromosomes and others contain 47, which contain an extra chromosome 21
mosaicism
43
missing a sex chromosome, webbed neck, spontaneous mutation, low pinnas, streak gonads, infertile
turner's
44
extra sex chromosome, single most common cause of male infertility, infertile, form man boobs at puberty,
klinefelters
45
What is the hallmark of chromosomal disorders
intellectual disabilities
46
AD
Joint problems, distinctive facial features (cleft lip/palate, small lower jaw, & tongue in back of mouth)
stickler syndrome
47
AD
Vestibular schwannoma
Lisch nodules, >6 cafe au lait spots, tumors on and under skin
NF1
48
AD
Bilateral acoustic neuromas, 100% penetrance,
nf2
49
AD
Blue sclera, vertigo, tinnitus, multiple bone fractures
osteogenesis imperfecta
50
Variable (AR, AD, X linked)
Progressive neurodegenerative disease characterized by polyneuropathy (affects motor & sensory nerves, absent limb reflexes, muscular atrophy), likely due to auditory neuropathy
Charcot-Marie Tooth
51
AR
Long QT interval, SIDS
JLNS
52
X linked
Abdominal hernia, contractures of arms, hands, etc.), death by 10-15 yrs
hunter syndrome
53
Pigment disturbances, deafness, AD, b/l upper extremity defects, abnormal limbs&joints
waardenburg
54
Sudden onset of severe/profound SNHL when exposed to aminoglycosides, not dose dependent
Aminoglycoside-induced ototoxicity
55
Congenital stapes fixation w/ perilymph gusher
DFNX0
56
AD, fish mouth, first arch syndrome, peanut ear, coloboma
treacher collins
57
AD, polycystic large kidneys, mixed SNHL, branchial preauricular pits
BOR
58
x linked, dementia, cataracts, SNHL
norrie
59
retinitis pigmentosa, progressive HL
ushers
60
AD, Early fusion of bones, atresia of EAC, ossicular deformities, CHL
crouzons
61
Most common in caucasian females, otic capsule, AD
OTSC
62
Multifactorial, unilateral facial structures from first and second arch, CHL, skeletal issues
OAV
63
Renal failure, hematuria, SNHL that is progressive, vision loss
alports
64
Impairment of speech perception in noise due to disruption of synchronous VIII N firing, in tact OAE’s but absent reflexes and ABR
ANSD
65
Caused by GAA trinucleotide triplet expansion, babinski reflex, nystagmus
Friedreich’s ataxia
66
Which is false for NF-2
High risk for meningioma
100% penetrance
Close relatives present with it?
Intellectual disability
Minimal cafe au lait spots
Intellectual disability
67
AR, thyroid problems, hypothyroidism, SNHL,
pendred
68
What is associated with Mondini malformation?
charge
69
Characterized by coarse facial features, shortened lifespan, intellectual disability, large babies
Hurler syndrome
70
HL, displacement of the inner eyes, thickened eyebrows, white forelock
Waardeburgh type I (AD?)
71
Urine analysis & routine blood tests
alports
72
Almost all of the autosomal dominant conditions show post-lingual progressive hearing loss and all recessive conditions are associated with severe to profound SNHL, which is prelingual (probably congenital)
TRUE
73
Connexins are found only in the auditory system
False, Inner ear (including utricle & saccule- nonsensory epithelial) , skin, liver, bladder, placenta, Etc
74
Missense non-conservative mutation
This mutation happens when the code is read wrong and the product of the code is harmful and different from the intended code. It codes for a different amino acid
75
Something harmful that occurs in the environment that causes a mutation only of the developing embryo/fetus.
Example:
Zika virus
TERATOGEN
76
Which is different?
Adenine
Thymine
Guanine
Cytosine
Methionine
Methionine
77
Which is different?
Phenylalanine
Uracil
Tryptophan
Proline
Tyrosine
Uracil
78
Point mutation that prematurely codes for stop codon is called
Nonsense mutation
79
Genetic crossing over in ____ prevents children from being clones of their parents
Prophase I
80
Which is NOT stop codon?
UAA
UAG
AUG
UGA
UUU
AUG
UUU
81
Which neural tube defect contains remnants of all 3 germ layers
dermoid cyst
82
Dna structure allows for replication and affords protection against DNA loss and damage
true
83
Sperm do not contribute _________ to fertilized egg because they shed the ______ prior to fertilization
Mitochondria, cytoplasm
84
Future ET develops from the _____ pharyngeal pouch
first
85
Future ______ develops from first pharyngeal groove/cleft
eac
86
Pinna develops from 6 mesenchymal projections called
auditory hillocks
87
Inner ear develops from the ____ and cochlea develops from pocket of lower pole of the ____
otic placode
saccule
88
Adenine and guanine are two ring structures called ______ and thynine and cytosine are 1 ring structures called
Purines
Pyrimidines
89
vertical transmission, only need 1 bad gene, no carriers, 50% chance per pregnancy
AD
90
Consanguinity is an issue, horizontal transmission, 25% chance per pregnancy, carriers involved
AR
91
Different gene from each parent on each chromosome
heterozygous
92
same gene from each parent on each chromosome
homozygous
93
ONLY from mom, 100% chance to both sexes
All children (M & F) of affected MOTHERS have 100% risk of infections
Father doesn’t pass it on because sperm loses cytoplasm prior to fertilization
eve gene
mitochondrial
94
How to read 1q2_4
Chromosome 1, long arm q, band 2 region 4
95
Process which phenotype differs depending on which parent transmits the allele/chromosome
genomic imprinting
96
what are 2 examples of genomic imprinting
Prader Willi Syndrome- paternal
Angelman Syndrome- maternal
97
Abnormal number of chromosomes
aneuploidy
98
Which chromosome is not acrocentric?
13, 14, 15, 22, 21, Y, 10
10
99
If two deaf parents are inquiring about their child having a HL, but they have a hearing child, what is the possible explanation?
Complimentary AR transmission
100
What is huntingdon’s disease an example of?
Allelic expansion and genetic anticipation
101
With X linked dominant, the dad will pass it on to
100% chance to F, 0% chance to M
102
x linked recessive
From mom - 50% chance carrier to F, 100% M
From dad - 100% carrier F
103
GJB2 gene Cx26
DFNB1A
104
GJB6 gene Cx26
DFNB1B
105
Cochlear hair cells once fully differentiated remain in the _____ phase of the cell cycle
go
