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BECOM 1 > BECOM Exam #3 > Flashcards

BECOM Exam #3 Flashcards

1
Q

Helicase

A

separates the helix by breaking the hydrogen bonds between complementary bases

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2
Q

Single Stranded Binding Protein (SSBP)

A

prevent reannealing of the duplex during DNA replication

-binds to split single stranded DNA once split by helices so it can not bind back together

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3
Q

Topoisomerase

A

prevent DNA supercoiling during DNA replication

-doxorubicin poisens

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4
Q

Primase

A

lays down DNA primer for DNA replication

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5
Q

DNA Pol III

A

synthesizes daughter strand 5’-3’ direction (continuously on the leading strand, discontinuously on the lagging strand). This results in Okazaki fragments on the lagging strand.

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6
Q

DNA Pol I

A

replaces the RNA bases of the primer with DNA bases in-between Okazaki fragments

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7
Q

DNA ligase

A

facilitates the formation of phosphodiester bonds and joins Okazaki fragments

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8
Q

ribonucleoprotein telomerase

A

synthesized telomeres

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9
Q

telomeres

A

-are added to the 3’ end of the template strand so there is a over hang and no essential genes are effected

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10
Q

T loop

A
  • the over hating 3’ end loops around and inserts itself into a section of the double stranded telomere
  • shelterin protein complexes that specifically bind to telomeric DNA repeats and protects them from being recognized by DNA repair proteins
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11
Q

exonuclease DNA replication

A
  • a section of DNA polymerase
  • 3’-OH end of the daughter strand is displaced into exonuclease subunit because of mismatched base pairing
  • removes mismatched base pair
  • also used to remove primer from Okazaki fragments
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12
Q

PCNA

A

sliding clamp that makes DNA polymerase more efficient

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13
Q

DNA MYH glycosylase

A

recognizes and cleaves the damaged DNA bases in DNA excision repair leaving a sugar with no base

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14
Q

AP endonuclease

A

recognizes sugar with no base during DNA excision repair and cleaves DNA chain

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15
Q

Poly-ADP-ribose polymerase

A

binds to the strand break and recruits other repair proteins during DNA excision repair

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16
Q

Nonhomologous End Joining

A
  • is used in non dividing cells to repair double stranded breaks in DNA
  • single stranded bases are removed by Artemis and the two stands are then put back together by DNA ligase
  • Damaged DNA is removed no repaired
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17
Q

Homologous Recombination Repair

A
  • actively dividing cells
  • sister is used as a template for repair
  • MRN complex binds to end of DNA and activate ATM (Kinase)
  • BRCA1, PALB2 and BRCA2 are recruited
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18
Q

HATs

A
  • transfer acetyl group from acetyl-CoA to lysine residues in histone tails
  • loosens DNA
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19
Q

HDAC

A
  • removes acetyl group from acetyl-CoA to lysine residues in histone tails
  • tightens DNA
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20
Q

DNA Methyltransferase

A
  • associates with the 6’ carbon of cytosine and adds a methyl group to the 5’ carbon
  • This favors the incorporation of DNA into heterochromatin (tightly packed, no transcription)
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21
Q

Silencer

A
  • are DNA elements that act at a distance to repress transcription of their target genes
  • Silencers bind transcription factors called repressor proteins that induce bends in DNA
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22
Q

Enhancer

A
  • Enhancer sequences increase the level of transcription of specific genes
  • They bind proteins that interact with the proteins that are bound to gene promoters, and together the promoters and enhancers drive gene expression
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23
Q

thyroid hormone receptor

A
  • THR bound to RXR (heterodimer)
  • Heterodimer bound to corepressor
  • Thyroid hormone binds to THR and conformational change binds coactivator
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24
Q

which end is capped and which end get a poly a tail

A

5’ cap 3’ poly a tail

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25
Q

Initiation

A
  1. small ribosomal subunit binds to mRNA strand
  2. UAC (methionine) bind to to AUG
  3. large subunit binds and methionine is in the P site
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26
Q

eIF3

A

prevents premature association of 40S and 60S subunits

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27
Q

eIF2-GTP

A
  • binds to initiator tRNA
  • eIF2-GTP/tRNAmet join the 40S ribosomal subunit with participation of eIF3 and other eIFs
  • inactive when phosphorylated
  • heme dependent
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28
Q

Insulin activates

A

eIF4

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29
Q

Peptidyl transferase = aminoacyl-tRNA

A

catalyzes peptide bond formation between amino acids attached to tRNAs at the P and A sites

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30
Q

Using GTP hydrolysis, eEF2

A

translocates the ribosome, moving it three nucleotides toward the 3’ end of the mRNA

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31
Q

termination

A

release factors bind to stop codon at the A site he polypeptide bound to the tRNA at the P site is then released while the RF is ejected and the ribosomal subunits separate

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32
Q

Tetracyclines, including doxycycline

A

prevent the binding of aminoacyl-tRNA by blocking the A (aminoacyl) site of the 30S ribosome

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33
Q

Aminoglycoside antibiotics (Streptomycin, Kanamycin and tobramycin)

A

have an affinity for the 30S ribosome subunit and don’t allow it to bind with 50s subunit

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34
Q

Erythromycin, roxithromycin, and clarithromycin (macrolides)

A
  • prevent elongation at the transpeptidation step of synthesis by blocking the 50S polypeptide export tunnel.
  • binds to the 23S rRNA component of the 50S ribosome and interferes with the assembly of 50S subunits.
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35
Q

Lincomycin and clindamycin

A

specific inhibitors of peptidyl transferase

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36
Q

B. pseudomallei toxin

A

targets the translation initiation factor 4A (eIF4A)

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37
Q

Shigella dysenteriaeand enterohemorrhagic strains ofE. coli

A

remove a specific adenine from 28S ribosomal RNA

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38
Q

Diphtheria toxin

A
  • 0inactivate eukaryotic elongation factor eEF2, thereby inhibiting eukaryotic protein synthesis (prevents translocation)
  • DT targets a PTM-modified histidine residue of EF2 called diphthamide, which is only present in eukaryotes and archaea
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39
Q

Mutation in coding region results in

A

abnormal protein

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40
Q

Regulatory region mutation results in

A

excessive amount of protein

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41
Q

Translocation results in

A

novel protein

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42
Q

Gene amplification results in

A

excessive amount of protein

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43
Q

Stop codons

A

UAA, UAG, UGA

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44
Q

BAD

A

proapoptotic

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45
Q

p21

A

universal cyclin/cdk inhibitor (CKI), it prevents the phosphorylation of Rb, keeping Rb bound to E2F

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46
Q

Rb/E2F

A

Rb usually sequesters the transcription factor E2F (family of transcription factors)

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47
Q

p53

A
  1. stimulate transcription of p21
  2. cyclin/CDK inhibitor
  3. activates genes for apoptosis when DNA is not repaired
  4. activates transcription of DNA repair enzymes
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48
Q

MDM2

A
  • down regulation of p53

- tags p53 for degradation when DNA is successfully repaired

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49
Q

β-catenin

A
  • translocates to the nucleus and activates transcription of myc and cyclin D when not bound to APC
  • when bound to APC –> degraded
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50
Q

HOXD13 mutations

A

causes webbed fingers, too many fingers, or not enough fingers

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51
Q

All axial and appendicular skeletal muscles, and all of the skeleton except the cranium, come from the

A

paraxial mesoderm

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52
Q

Limb skin, hair, skin glands, and nails

A

surface ectoderm

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53
Q

Proximodistal axes of development

A

pectoral/pelvic girdle -> digital tips

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54
Q

Dorsoventral axes of development

A
  • spinal column (back/dorsum) -> belly (front/anterior)

- Important for patterning the extensors dorsally and flexors ventrally

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55
Q

Anteroposterior axes of development

A

head -> tail (rostral -> caudal)

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56
Q

FGF10

A
  • starts limb bud growth

- FGF8 and FGF10 are important for continuing growth of the arm

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57
Q

Sonic hedgehog (Shh or SHH) is responsible for

A

Anteroposterior growth axis

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58
Q

apoptosis of hands and feet

A

loss of webbed fingers and toes

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59
Q

uplimb rotates

A

dorsally (laterally)

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60
Q

lower limb rotates

A
  • ventrally (medially)
  • so souls of feet will be on the ground
  • most problem where legs don’t rotate enough
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61
Q

what supplies the arteries of the upper and lower limb through development

A

primary axial artery

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62
Q

Amelia

A

Absence of limb(s)

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63
Q

Meromelia

A
  • Absence of parts of limbs

- Can be caused by HOX mutations and teratogens – remember thalidomide

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64
Q

Autosomal Recessive Inheritance

A
  • If both parents have the disorder, all children will have

- The sex ratio of affected offspring is expected to be equal

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65
Q

Autosomal Dominant Inheritance

A
  • Fathers can give to DAUGHTERS and SONS

- Males and females are affected in equal numbers

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66
Q

Autosomal Dominant Inheritance (Sex Limited)

A

Male-limited precocious puberty, a sex-limited autosomal dominant disorder expressed exclusively in males that affects secondary sex characteristics

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67
Q

Incomplete Penetrance

A

some individuals will not express the trait even though they carry the allele

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68
Q

X-linked Recessive Inheritance

A
  • A recessive male mated to a homozygous dominant female produces all offspring with the dominant phenotype, and all female offspring are carriers
  • Matings of recessive males with carrier females give half dominant and half recessive offspring of both sexes
  • Matings of homozygous recessive females with dominant males produce all dominant (carrier) female offspring and all recessive male offspring
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69
Q

X-linked Dominant Inheritance

A

-Males cant pass X linked trait to son

but all daughters will be effected

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70
Q

Random X-Chromosome Inactivation

A

one of two X chromosomes in each female somatic cell is randomly inactivated

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71
Q

HOX genes

A

a subset of homeotic genes, are a group of related genes that control the body plan of an embryo along the head-tail axis

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72
Q

Synpolydactyly mutation cause

A

HOXD13

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73
Q

Apical epidermal ridge

A

is a structure that forms from the ectodermal cells at the distal end of each limb bud and acts as a major signaling center to ensure proper development of a lim

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74
Q

what is derived from the paraxial mesoderm

A

All axial and appendicular skeletal muscles, and all of the skeleton except the cranium

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75
Q

what is derived from the surface ectoderm

A

Limb skin, hair, skin glands, and nails

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76
Q

Proximodistal

A

pectoral/pelvic girdle -> digital tips

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77
Q

Dorsoventral

A

spinal column (back/dorsum) -> belly (front/anterior)

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78
Q

Anteroposterior

A

head -> tail (rostral -> caudal)

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79
Q

Proximodistal growth axis of limb buds are induced by

A

FGF10 induction

AER secretes FGF8, FGF4

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80
Q

Zone of Polarizing Activity

A
  • is an area of mesenchyme that contains signals which instruct the developing limb bud to form along the anterior/posterior axis
  • located posteriorly
  • associated with Sonic hedgehog gene
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81
Q

apoptosis

A

loss of webbing

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82
Q

Upper limb rotates and movement

A
  • dorsally (laterally)

- Arm buds move cranially so the arm will get closer to the head w growth

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83
Q

Lower limb rotates

A

ventrally (medially)

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84
Q

Arterial supply to arm buds

A

primary axillary artery

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85
Q

Meromelia

A

Absence of parts of limbs

86
Q

Intramembranous Ossification

A
  • A mesenchymal stem cell, or MSC, is an unspecialized cell which can develop into an osteoblast.
  • Flat bones of the skull
87
Q

Endochondral Ossification

A
  • In intramembranous ossification, bone develops directly from sheets of mesenchymal connective tissue. In endochondral ossification, bone develops by replacing hyaline cartilage. Activity in the epiphyseal plate enables bones to grow in length (this is interstitial growth).
  • all but flat bone of the skull
88
Q

Secondary ossification centers

A
  • Tip of spinous and on each transverse process

- Two annular epiphyses in vertebral bod7

89
Q

two primary ossification centers

A
  • Dorsal and ventral
  • Fuse to form one center
  • Primary ossification centers on either side of neural arch
90
Q

Spina Bifida

A
  • Failure of vertebral arch to fuse

- Spinal cord, spinal nerves and meninges vulnerable to injury

91
Q

lateral mesoderm forms

A

Sternum

92
Q

Synaptotagmin

A

where Ca2+ binds to initiate SNARE protein -> exocytosis

93
Q

Synaptobrevin

A

runs through vesicle and attaches to membrane bound SNARE complex

94
Q

Acetylcholinesterase

A

Breaks down ACh to acetate and choline

95
Q

Ryanodine Receptors

A
  • receptor connecting t tubule and sarcoplasmic reticulum

- can be activated by calmodulin

96
Q

Troponin I

A

inhibits binding of myosin

97
Q

Troponin T

A

binds to tropomyosin

98
Q

Troponin C

A

binds to calcium

99
Q

H band

A

middle (myosin only)

100
Q

light I band

A

actin in between two myosin

101
Q

A band

A

actin and myosin overlap

102
Q

Role of ATP in skeletal muscle action

A
  • Myosin ATPase
  • Ca+2 pump in SR
  • Na+/K+ pump in sarcolemma
103
Q

Twitch

A
  • single stimulation of a muscle fiber

- short depolarization and short period of crossbridging => short weak contraction

104
Q

Treppe

A
  • staircase increase in muscle contraction as more and muscle fibers are stimulated
  • increase in force produced with each contraction
105
Q

tetany

A
  • fatigue
  • continued stimulation of maximal force
  • maximum speed of contraction, max force, inability to maintain force (fatigues)
  • Intracellular Ca2+ levels remain high or rise during tetany
106
Q

Incomplete tetany

A

repeated rapid contraction, recovery tension increases with each contraction

107
Q

Longer length muscle

A

greater velocity and less force

108
Q

Shorter length muscle

A

less velocity and greater force

109
Q

Slow vs Fast twitch ranking

A

Slowest Type 1 < Type 2a < Type X < Fastest Type 2b

110
Q

Power Output =

A

force X velocity

111
Q

High intensity exercise (sec-minutes) fatigue

A

Lack of blood flow: lack of O2Anaerobic metabolism formation of lactic acid and depletion of ATP

112
Q

Moderate intensity exercise(20-120min) fatigue

A
  • Lack of adequate blood flow: lack of O2Anaerobic metabolism formation of lactic acid and depletion of ATP
  • Glycogen depletion
113
Q

Low intensity exercise (2hr-days) fatigue

A
  • CNS fatigue: decrease in neurotransmitter in CNS leading to difficulties in maintaining muscle contraction, prolonged exercise
  • Glycogen depletion (CHO store within muscle)
  • Electrolyte depletion (Na+, K+, Ca2+)
114
Q

Myosin light chain phosphatase

A
  • smooth muscle relaxation

- force decreases

115
Q

Myosin light chain kinase

A
  • smooth muscle contraction

- force increases

116
Q

Unitary smooth muscle vs. multi unit smooth muscle

A

Unitary: single neuron (varicosity) innervation -> gap junction passes cellular response
Multi Unit: each cell must come in contact with a varicosity

117
Q

Tetrodotoxin

Local anesthetics

A

Nerve action potential

118
Q

Hemicholinium

Botulinus toxin

A

ACh release

119
Q

Curare

Succinylcholine

A

Endplate Potential

120
Q 
Organophosphates
Pyridostigmine (Myasthenia gravis)
A

Acetylcholinesterase

121
Q

Veratridine

Quinine

A

Muscle action potential

122
Q

Metabolic poison

Procaine

A

Muscle Contraction

123
Q

Phosphodiesterase

A

breaks down cAMP

124
Q

RYR1 vs RYR2

A

skeletal

cardiac

125
Q

lamellar granules

A

water-resistant glycolipid slows water loss

126
Q

type I keratins

A

acidic keratins

127
Q

type II keratins

A

basic keratins

128
Q

How does melanin protect skin

A
  • absorb energy with double bonded ring structure

- provide site for free radical binding

129
Q

Alternative splicing

A

processing of identical transcripts in different cells can lead to mature mRNAs with different combinations of exons and thus different polypeptides

130
Q

start codon (Kozak sequence)

A

AUG

131
Q

eIF4

A

is bound to the mRNA and bind it to the 40s subunit

132
Q

Release Factor (RF)

A
  • bind a stop codon in the A site
  • The polypeptide bound to the tRNA at the P site is then released while the RF is ejected and the ribosomal subunits separate
  • bacteria: multiple RF eukaryotes: single RF
133
Q

Rb gene

A

-sequesters trans factor eF2 by binding to it

134
Q

APC mutation lead to

A
  • colon cancer (Familial adenomatous polyposis)

- cant bind β-catenin

135
Q

Autosomal Dominant Inheritance

A
  • Each individual who has the disease has at least one affected parent
  • Males and females are affected in equal numbers
136
Q

Autosomal Recessive Inheritance

A
  • If both parents have the disorder, all children will have it
  • Individuals who have the disease are often born to parents who do not
  • Fathers can give to DAUGHTERS and SONS
  • If father gives to all his sons sex limited
137
Q

X-linked Dominant Inheritance

A

-Dominant males mated to homozygous recessive females pass the trait to all their daughters and none of their sons

138
Q

DHPR (Dihydropryidine receptor)

A

voltage sensitive receptor in the t tubule

139
Q

Role of ATP in skeletal muscle

A
  1. Myosin ATPase
  2. Ca+2 pump in SR (Sequesters Ca+2 )
  3. Na+/K+ pump in sarcolemma (Establishes resting membrane potential)
140
Q

Action Potential vs End Plate Potential

A
  • Action Potential is all-or-none response

- End Plate Potential is a graded potential

141
Q

Longer muscle length (ML) and fiber length (FL)

fusiform

A

Greater velocity

142
Q

Shorter muscle length (ML) and fiber length (FL)

pennate

A

Greater force

143
Q

Power output =

A

force x velocity

  • more force = less velocity
  • less force = more velocity
144
Q

isotonic

A

same force

145
Q

isometric

A

same length

146
Q

Connexins

A

channels in the gap junction of cardiomyocytes that allow electrical connection

147
Q

preload

A

amount of force/stress applied to muscle before contraction

148
Q

afterload

A

amount of force the muscle must contract against in order to shorten

149
Q

NE/EPI vs ACh effect on heart contraction

A

NE/EPI: inc contractile force

ACh: dec contractile force

150
Q

Inc in afterload

A

dec velocity

151
Q

inc in preload

A

inc in contractile force up to a certain point

152
Q

vernix caseosa

A

Exfoliated peridermal cells and sebum that covers infant and protects developing skin from constant exposure to amniotic fluid with its urine content during the fetal period

153
Q

melanocyte location and embryological origin

A
  • basal layer

- neural crest cells migrate into mesenchyme of developing dermis (neural crest -> melanoblasts ->melanocytes)

154
Q

thick skin lacks

A

Lacks hair follicles, arrector pili muscles and sebaceous glands but contains sweat glands

155
Q

epidermis and dermis origin

A

epidermis: ectoderm
dermis: somatic layer of lateral mesenchyme

156
Q

Ichthyosis

A

is a general term applied to a group of skin disorders resulting from excessive keratinization

157
Q

collodion

A

infant is covered by a thick, taut membrane that resembles collodion (a protective film) or parchment

158
Q

Nevus flammeus

A

denotes a flat, pink or red, flamelike blotch that often appears on the posterior surface of the neck

159
Q

Sebaceous glands

A
  • develop as cellular buds from the sides of developing epithelial root sheaths of hair follicles
  • secrete sebum
160
Q

Eccrine sweat glands

A

They develop as cellular buds from the epidermis that grow into the underlying mesenchyme

161
Q

apocrine sweat glands

A
  • The glands develop from downgrowths of the stratum germinativum of the epidermis
  • As a result, the ducts open into the canals of the hair follicles superficial to the entry of the sebaceous gland ducts
  • found in pubic, axilla, and areolae region
162
Q

mammary glands

A
  • specialized sweat glands, multiple buds come off forming lactiferous ducts
  • The breasts of newborns contain lactiferous ducts but no alveoli
163
Q

witch’s milk

A

-These transitory changes are caused by maternal hormones passing through the placental membrane into the fetal circulation

164
Q

Gynecomastia

A

refers to the development of the rudimentary lactiferous ducts in the male mammary tissue

165
Q

Athelia

A

Absence of Nipples

166
Q

Amastia

A

Absence of breast

167
Q

hair bulb (epithelial cells) are invaginated a small mesenchymal cell called

A

hair papilla

168
Q

Arrector pili muscles and origin

A

are small bundles of smooth muscle fibers that differentiate from mesenchyme surrounding hair follicle

169
Q

Alopecia

A

is the absence or loss of hair

170
Q

Nail growth

A

nail plate grow over the nail field (keratinized)

171
Q

Congenital anonychia

A

is the absence of nails at birth and is a permanent abnormality

172
Q

skin physical barriers

A

resistance to mechanical stress and absorption/evaporation of substances (water)

173
Q

skin biological barriers

A 
Dendritic cells of epidermis
-Present foreign antigens to white blood cells 
DNA
-Its electrons absorb UV radiation
-Radiation converted to heat
174
Q

skin chemical barrier

A 
Skin secretions 
-Low pH retards bacterial multiplication
-Sebum and defensins kill bacteria
Melanin
-Defense against UV radiation damage
175
Q

skin pH, weight, and percent of body

A
  • pH 4.7
  • 6,20 lbs
  • 15%
176
Q

epidermis cells

A

keratinocytes, melanocytes, dendritic cells, tactile (Merkel) cells

177
Q

dermis cells

A

primarily fibroblasts

178
Q

Hypodermis cells and function

A
  • adipocytes

- Insulates body, Energy reserve, Cushions and protects skin, Mobility over underlining structures

179
Q

Stratum granulosum contain

A
  • lamellar granules that secrete lipids (water-resistant)
  • everything dead above
  • beginning of keratinization
180
Q

Keratinocytes

A

Produce fibrous protein keratin (more produce as you get closer to surface)
Most cells of epidermis
Tightly connected by desmosomes

181
Q

stratum spinosum mostly contain

A

melanosomes and dendritic cells

182
Q

Dermis layers

A
  • Papillary

- Reticular: provide strength and resiliency bind water

183
Q

Epidermis fuel source

A
  • Blood glucose diffusing from dermis to epidermis is primary fuel source
  • Extracellular glucose is greater than intracellular glucose suggesting lack of active transport i.e. insulin mediated uptake and more likely passive diffusion
  • Upon enter keratinocytes, glucose is metabolized primarily anaerobically via glycolysis to produce lactic acid
184
Q

↑ Body Core temp

A

Thermoreceptors in hypothalamus (primary driver) and skin (secondary) respond -> cholinergic stimulation -> vasodilation of blood vessels in dermis

185
Q

↓ Body temp

A

Thermoreceptors in hypothalamus (primary driver) and skin (secondary) respond -> adrenergic stimulation -> vasoconstriction of blood vessels in dermis

186
Q

Eccrine Sweat Glands are found where

A

Abundant on palms, soles, and forehead

187
Q

Modified apocrine glands

A
  • Ceruminous glands—lining of external ear canal; secrete cerumen (earwax)
  • Mammary glands – secrete milk
188
Q

type I keratin

A

acidic keratins (contain acidic acids)

189
Q

type II keratin

A

basic keratins (contain basic amino acids)

190
Q

Transglutaminase

A

lysine + glutamine forms amide bond

  • gives structural stability to keratins int. filaments
  • doesn’t just happen in keratin
  • Ca2+ DEPENDENT
191
Q

keratin is made up of and give it

A

Intermediate filaments provide mechanical strength and resistance to shear stress

192
Q

UVA vs. UVB

A

UVB: skin cancer, cataracts and sun burn
-damage sup. epiderms
UVA: longer wavelength penetrate deeper
into dermis

193
Q

Brown, Black, Pheomelanin (red/yellow tint) melanin structure

A

double bonded ring absorbs energy and provides site for free radicals to bind

194
Q

melanin is derived from

A

tyrosine which can be derived from phenylalanine

195
Q

enzyme used to convert tyrosine to melanin and what is it dependent on?

A
  • Phe -> tyr -> Dopa -> melanin

- tyrosine hydroxylase Cu2+

196
Q

What happens to DNA when exposed to UV radiation

A
  • Cyclobutane pyrimidine dimers

- Two adjacent pyrimidines form a covalent dimer

197
Q

nucleotide excision repair fixes

A

UV damaged DNA that as been dimerized

198
Q

Nonhomologous end joining occurs in

A

non dividing cells

199
Q

homologous recombination repair occurs in

A

actively dividing cells

200
Q

Zone of Polarizing Activity (ZPA) is responsible for establishing

A

the anterior-posterior (dorsal-ventral) axis

201
Q

lanugo hair

A

Help hold vernix caseosa on the skin, which protects the skin

202
Q

Hypertrichosis

A

is growth of hair in excess of normal

203
Q

vellus hair

A

Pale, fine body hair of children and adult females

204
Q

Terminal hair

A

arse, long hair of eyebrows, scalp
At puberty
Appear in axillary and pubic regions of both sexes
Face and neck of males

205
Q

methylation amino acid

A

cytosine

206
Q

Acrania

A

Complete or partial absence of

neurocranium

207
Q

Meroencephaly

A

Failure of cranial end of neural
tube to close
• Failure of neurocranium to form

208
Q

Microcephaly

A

Small calvaria
• Brain and neurocranium fail to
grow

209
Q

hemivertebra

A

improper migration of sclerotomal cells

210
Q

BAX

A

If DNA not repaired, p53 activates genes involved in apoptosis

211
Q

ACTH

A

protein from POMC that helps release cortisol for anti inflammatory

BECOM 1 (4 decks)

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