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Block 1 > Week 2 Random > Flashcards

Week 2 Random Flashcards

1
Q

Timing of migration of Primordial germ cells (PGCs)

A

2nd week: formed in epiblast

3rd week: move to the wall of the yolk sac

4th week: migrate to the developing gonads

5th week: arrive in the gonads then meiosis In the mouse, ~100 PGCs leave the yolk sac →6-7 rounds of mitotic multiplication →4000 enter the primitive gonads

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2
Q

Fate of misdirected PGCs

A

Die or Form Teratomas

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3
Q

Stages of formation of gametes

A

1) Movement of PGC to gonads
2) Mitosis in gonads (overproduction followed by density mechanism) in oogonia divide only during development, and in males spermatogonia divide during development and puberty
3) Meiosis
4) Structural and Functional maturation of Eggs and Sperm Oogenesis and Spermatogenesis

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4
Q

Oogenesis

A

2 million primary oocytes present in the ovaries at birth, only ~40,000-survivie until puberty.

400 (1 per menstrual cycle) are ovulated. Primary oocytes remain in prophase and do not finish their first meiotic division before puberty is reached.

At puberty, one activated primary oocyte produces two haploid cells asymmetric cell division The first polar body The secondary oocyte

The secondary oocyte arrests in metaphase II and is ovulated If penetrated by sperm the second oocyte completes meiosis II, One large ovum (the functional gamete) A tiny second polar body

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5
Q

Describe spermatogenesis

A

Spermatogonia (diploid)

Spermatocytes (enter meiosis)

Spermatids (haploid)

->spermiogenesis-> during which they acquire a tail (flagellum) and an acrosome that develops from the Golgi body

Sperm

Spermiogenesis:

  • formation of acrosome (penetration enzymes)
  • condensation of nucleus
  • formation of neck, middle piece, and tail
  • shedding of most of the cytoplasm that is phagocytized by Sertoli cells
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6
Q

Spermiation

A

Excess cytoplasm and is released into the lumen of the seminiferous tubule

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7
Q

How Kareotype is done

A

Leukocyte are isolated, propagated, and toxin are injected Cells are squashed on microscope slide Lightly treated with protease to unwind DNA Stained with Geimsa (non-specific) stain- (total 850 bands; about 50/csome)

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8
Q

Position of centromere

A

Metacentric (middle) submetacentric- towards one end acrocentric - at the end

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9
Q

p vs q

A

p is short arm q is long arm 7p22.2 46,XY,inv(9).(p11q12)

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10
Q

FISH

A

fluorescence in situ hybridization Specific nucleotide probes abeled with fluorescent dyes can be hybridized to the solated chromosomes or nuclei on microscope slides and nalyzed by fluorescence microscopy.

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11
Q

Types of probes in FISH

A

Locus specific (label single gene or region) Centromeric probe (labels a specific pair of chromosomes at their centromere) Chromosome painting probe (paint entire chromosome)

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12
Q

Two preps for FISH

A

Metaphase nuclei: visualize chromosome structure Interphase nuclei: determine number

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13
Q

SKY

A

Spectral Karyotiping FISH with different colors Use in cancer treatment

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14
Q

Why chromosomal studies are important

A

Confirmation/determination of diagnosis Prognosis Treatment Monitoring disease – disease progresion and relapse

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15
Q

Microarray SNP

A

This analysis is designed to look for imbalances across the genome using SNP (Single Nucleotide Polymorphism) based technology. The SNP microarray testing has probes that can detect imbalances related to hundreds of common Balanced or low level mosaic chromosome changes will not be identified with this technology

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16
Q

Use of Cell Free Fetal DNA

A
  • Maternal age 35 years or older at delivery - Fetal ultrasonographic findings indicating an increased risk of aneuploidy - History of a prior pregnancy with a trisomy - Positive test result for aneuploidy, including first trimester, sequential, or integrated screen, or a quadruple screen. - Parental balanced robertsonian translocation with increased risk of fetal trisomy 13 or trisomy 21. - 10-15% DNA in mother blood is free fetal DNA - The goal of the test is very specifc trisome 13, 18, 21, XO, XXY
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17
Q

false positive false negative

A

Type 1 error, 1-accuracy Type 2 error, 1-sensitivty

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18
Q

Balanced / Unbalanced abnormalities of chromosomes

A

Duplications Inversions Inertions Isochromosomes

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19
Q

der(14;21)

A

Chromosome derived from 14 and 21

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20
Q

Balanced Translocations types

A

Reciprocal translocation Parts of chromosomes are exchanged Can result in mutations at break points or can be unaffected. Problems with segregation at gametogenesis Robertsonian translocation- centric fusion of two chromosomes. No lost coding sequences, carrier unaffected. Problems with segregation at gametogenesis.

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21
Q

Balanced vs. Unbalanced chromosomal rearrangements chraracteristic and types

A

Usually lethal 1) Spontaneous new mutation 2) Unbalanced inheritance from balanced rearrangements

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22
Q

Reciprocal translocation

A

Balanced chromosomes exchange

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23
Q

chromosomal studies can help with

A

Diagnosis (confirmation/determination) Prognosis Recurrence Risk

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24
Q

Amniocentesis

A

a prenatal diagnosis of chromosomal abnormalities and fetal infections, and also used for sex determination in which a small amount of amniotic fluid, which contains fetal tissues, is sampled from the amniotic sac surrounding a developing fetus, and the fetal DNA is examined for genetic abnormalities

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25
Q

Cordocentesis

A

highly specialized prenatal test in which a sample of the baby’s blood is removed from the umbilical cord for testing

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26
Q

Cytogenetics techniques

A

1) Karyotyping
2) FISH
3) Microarray SNP Analysis
4) Cell free fetal DNA in Maternal Plasma

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27
Q

How does FSH effect ovary?

A

Production of estrogen

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28
Q

What are the functions of Estrogen?

A

Proliferation of endometrium

Thinning of the cervical mucus

Stimulate pituitary to secrete LH

LH surge at mid-cycle-> ovulation

Stimulate progesterone production

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29
Q

What cells that produce estrogen in female in ovary?

A

granulosa and thecal cells

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30
Q

What are LH surge effects?

A

completion of meiosis I -> preovulatory follicle; arrested in metaphase of meiosis II: 3hrs before ovulation

On ovarian surface:

LH↑→Collagenase↑→Digestions of fibers around the follicle

LH↑→Prostaglandin↑→muscular contraction

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31
Q

What are cells and their function in Corpus lueteum?

A

Lutean cells: granulosa cells, thecal cells

Progesterone + Estrogen (turns uterine into secretion phase)

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32
Q

How long does it take for an egg to go from ampulla to uterine lumen?

A

3-4 days

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33
Q

Where does the fertilization occur?

A

At the ampula of uterine tube

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34
Q

What secretes hCG?

A

syncytiotrophoblast

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35
Q

When does the corpus luteum stop to produce progesterone?

A

nProgesterone production until the end of 4th month: trophoblastic secretion of progesterone becomes adequate.

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36
Q

Name three phases of fertilization

A

Phase I: penetration of the corona radiata

Phase II: penetration of zona pellucida

Phase III: Fusion of the oocyte ad sperm cell membranes

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37
Q

What is Capacitation?

A

(wash the sperm by folliciular tubule): Maturation of sperm in female reproductive tractà Removal of the glycoprotein coat and seminal plasma proteins from the sperm plasma membrane (Important for IVF invitro fertiliation and IUI)

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38
Q

What is Acrosome reaction?

A

Release of enzyme by sperm to dissolve zona pellucida (ZP)

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39
Q

What events are triggered by entry of sperm to an egg?

A

Cortical and zona reactions: to prevent polyspermy (forming cortical granules)

Oocyte completes meiosis II

Egg is activated

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40
Q

What are Blastomeres?

A

2-, 4-, 8-cell stages, cells →smaller and smaller

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41
Q

What are the results of fertilization?

A

Restoration of diploid number of chromosomes

Sex determination (at fertilization)

Initiation of cleavage ge:en-US’>Cell free fetal DNA in Maternal Plasma

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42
Q

How does Blastocyst integrate in uterus?

A

ZP degenerates → uterine fluid penetration → Blastocele (cavity) formation

Inner cell mass → embryoblast

outer cell mass → trophoblast, epithelial wall

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43
Q

What are the three epithelial layers in endometrium?

A

Compact layer, spongy layer, and basal layer

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44
Q

Contraceptive methods:

A

Barrier

Hormone-based

IUD nRU-486 (mifepristone): potent progesterone antagonist nSurgery: Vasectomy & tubal ligation

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45
Q

trophoblast differentiation

A

Week 2 Day 8

Cytotrophoblast (mononucleated) migrate in the Syncitotrophoblast region and lose connection

Syncytiotrophoblast (multinucleated without border)

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46
Q

When and how embroyblast differentiate?

A

Week 2 Day 8

Hypoblast layer (adjacent to blastocyst cavity)

Epiblast layer (adjacent to the amniotic cavity)

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47
Q

When and where does the amniotic cavity form?

A

Week 2 Day 8

Surrounded by epiblast cells

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48
Q

When and what makes amniotic memberane?

A

Week 2 Day 8

Amnioblast (epiblast cells that adjacent to the cytotrophoblasts)

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49
Q

What are lacunae? How do they form? Where do they appear? When do they appear?

A

Week 2 Day 9

Vacuoles fuse in syncytiotrophoblast

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50
Q

What types of cells are present in hypoblast and epiblast during Day 9?

A

Epiblast – columnar

Hypoblast – cuboidal

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51
Q

What is fibrin coagulum?

A

A plug that seal the outer layer of endometrium after the embryo implants in uretus.

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52
Q

When does the lacuna becomes continous with sinusoids?

A

Week 2 Day 11-12

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53
Q

What is the name of a layer that surrounds Secondary yolk sac?

What is the name of a layer that surrounds amniotic cavity and chorionic cavity?

When do they appear?

A

Week 2 Day 11-12

Extraembryonic splanchnic mesoderm.

Extraembryonic somatic mesoderm.

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54
Q

What is the name of the cavity that is surrounded by extrasomatric membrane?

A

Chorionic caivty

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55
Q

What are the extension of cytotrophoblast called?

When and where do they grow?

A

Week 2 Day 13

Primary villi

They grow in syncytiotrophoblast

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56
Q

When and where does the secondary yolk sac come from?

A

Week 2

It pinches off from the primitive sac.

Also called definitive yolk sac.

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57
Q

What is the exocoelomic cavity?

A
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58
Q

What is the chorion composed of

A

Week 2

Extraembryonic somatic mesoderm

syncytiotrophoblast

cytotrophoblast

59
Q

What is name that connects embryo to the chorion and what does it become?

A

Week 2

Connecting Stalk

Umbilical cord

60
Q

Decidua reaction

A

Week 2 Day 11

Endometrium cells become polyhedral and prepare for implantation.

61
Q

Which chromosomes regulate embryoblast?

Which chromosomes regulate trophoblast?

A

Female

Male

62
Q

What types of cells are in epiblast?

A

Pluripotent.

63
Q

What is the first site of hematopoesis?

A

Primary Yolk Sac

64
Q

beta-hCG uses

A

Early pregnancy tests

Detecting may have hCG levels low. In normal pregnancy, hCG levels double every 2-3 days.

65
Q

What forms extraembyronic mesoderm?

What does this extraembryonic mesoderm become?

A

Migration of epiblasts

Splanchnic mesoderm

Somatic mesoderm

66
Q

Utero-placental circulation

A

Maternal blood lacunae form in the endometrium by invasion of syncytiotrophoblast + Chorionic villi = EARLY PLACENTA

Blood starts flowing in the trophoblast.

67
Q

What are the two components of future planceta?

A

Endometrium and chorion

68
Q

Oocyte maturation inhibitor

A

Inhibits progression of oocytes from birth
Small peptide

69
Q

Stages in egg development

A

PRIMODIAL FOLLICE
cells become cuboidal and produce stratified epithelium of granulosa cells =
PRIMARY FOLLICLE
theca folliculi (stromal cells) separates it from connective tissue
zona pellucida (layer of glycoproteins on the surface of the oocyte, ofrming the zona pellucida)
inner cells become theca interna and outer into theca externa (fibrous capsule)
Antrum develops between granulosa cells
Cumulus oophorus forms around egg
MATURE GRAAFIAN FOLLICLE

70
Q

What is the name of the cell formed by Cleavage?

A

Blastomere

71
Q

Morula

A

16 cell ball
Composed of inner and outer cell mass
The inner cell mass give rise to the embryo proper
The outer cell mass give rise to the trophoblast which contributes to placenta

72
Q

Blastula

A

Uterine fluid enters between cells
Blastocele forms
Cells of the inner cell are called embryoblast and outer cell mas trophoblast
Zona pellucida dissapears
L selectin mediate carbohydrate binding

73
Q

When does the gastrulation begin?

What is gastrulation?

A

Week 3

Formation of all three germ layers: ectoderm, mesoderm, and endoderm

74
Q

What are three components of primitive streak?

A

Node, Pit, and Groove

75
Q

Where does the primitive streak go from and to?

A

From Cloacal membrane (anus) to Buccopharyngeal membrane (mouth).

76
Q

Ovulation steps

A

Meiosis II is initiated
3 hours before ovulation arrested in methaphase
surface of ovary bulge
stigma (avascular spot) appear
LH increases collagenase activity
Prostaglandin levels also increase
Cumulus oophorus breaks free
Some of the cumulus oophorus cells then rearrange themselves around the zona pellucida to form the corona radiata.

77
Q

Where are epiblast and hypoblast fused?

A

Buccopharyngeal membrane (mouth) and cloacal membrane (anus)

78
Q

What does the gastrulation form?

A

Definitive Endoderm

The Intraembryonic Mesoderm

Trilaminar Embryo

79
Q

What happens if primitive streak does not dissapear?

A

It forms a sacrococcygeal tumor (in newborn)

80
Q

Direction of mesoderm differentiation

A

Cranial to caudal

81
Q

Layers of mesoderm

A

Axial Mesoderm
Paraxial Mesoderm (somitomeres and somites)
Intermediate Mesoderm (urogentical system)
Lateral Plate Mesoderm (body wall)
Mesodermal contribution to the chorion (chorion)

82
Q

Prechordal plate

A

Sets the limit for the cranial migration of notochordal cells

Induces formation of the forebrain

83
Q

What are the results of the notochord formation?

A
  • formation is a series of steps involving fusing with the endoderm
  • defines primary axis, gives embryo some rigidity
  • induces formation of vertebral column
  • induces neuroectoderm to form neural plate
  • persists as the nucleus pulposus in the intervertebral disc until early childhood. Likely replaced by connective tissue
84
Q

3rd Week - Week of Threes

A
  • 3 parts to the primitive streak - groove, pit, node
  • 3 directions imparted by the primitive streak: dorsal-ventral, right-left, cranial-caudal
  • 3 definitive germ layers - ectoderm, mesoderm, endoderm
  • 3 types of villi - primary, secondary, tertiary
85
Q

2nd Week - Week of Twos

A
  • 2 trophoblastic layers - cytotrophoblast and syncytiotrophoblast
  • 2 layers from the inner mass - epiblast and hypoblast
  • 2 yolk sacs - primary and secondary
  • 2 extraembryonic mesoderms - splanchnic and somatic
  • 2 future cavities - chorionic and amniotic
  • 2 components of the placenta - endometrium and chorion
  • 2 clinical uses of betahCG
86
Q

What causes neurulation?

What will the neural plate form?

A

Prechordal plate and notochord induce neural plate formation in the overlying ectoderm.

Neural plate differentiates to neuroectoderm that forms the brain and spinal cord (CNS) during the embryonic period?

87
Q

What is the difference between primary, secondary, and tertiary stem villi?

A

Primary –cytotrophoblastic core covered by a synctial layer

Secondary – mesoderm layer, followed by cytotrophoblast, and then synctiotrophoblast

Tertiary villus – when blood vessels differentiate from mesoderm

88
Q

When tertiary villi form, which side contacts the embryo and which side contacts the baby.

A

Syncitotrophoblast covers vessels in villia

Cytotrophoblast contacts endometrium

89
Q

Composition of bilaminar embryonic disk.

A

Epiblast and hypoblast.

90
Q

Prochordral plate

A

Week 2

Fusion of epiblast and hypoblast that will become mouth.

91
Q

What are some of the different types of genes expressed?

A

Housekeeping genes

Specialized genes

Finely tuned genes

Normal vs. Diseased gene expression

92
Q

What type of proteins remodel chromatin?

A

ATP-dependent chromatin remodeling complexes

93
Q

What is The code-reader complex?

A

It is a scaffold protein bound to multiple proteins that recognize the chromatin modifications.

94
Q

Types of miRNA

A

Small nuclear RNA (snRNA) - mRNA processing

Small nucleolar RNA (snoRNA) – rRNA processing

Small cytoplasmic RNA (scRNA) – range of function

microRNAs (miRNAs) – post-transcriptional gene-silencing

95
Q

Whare are the functions of TFs

A

TFIID = TBP + TAFS

TFIIB = recognize BRE element

TFIIF = stabolize interaction TBP/TFIIB

TFIIE = attacts TFIIH

TFIIH = unwinds DNA; phosphorylateion CTD; releases RNA pol from the promtoter

96
Q

What are enzymes involved in mRNA editing?

A

Phosphatase

Guanyl transferase

Methyl transferase

97
Q

Alternative Splicing mechanisms

A

Exon skipping

Mutually exclusive exons:

Alternative 5’ donor site:

Alternative acceptor site:

Intron retention:

“Cryptic splice site” - a site whose sequence resembles an authentic splice site and which might be selected instead of the authentic site during aberrant splicing

98
Q

Domainds of TFs

A

DNA-binding domain (DBD).

Dimerization domain

Activation domain.

99
Q

HOX genes

A

They control the fundamental architectural plan of the developing embryo.

They are 180 bp long genes, coding for 60 (180 ÷ 3) amino acid long proteins.

They contain the so-called “homeodomain” consisting of a DNA-binding Helix1-Helix2-Helix3 motif (A). Helix3 occupies the major groove of DNA, while the N-terminal arm binds to the minor groove (B).

100
Q

Effects of ubiquitin

A

Monoubiquitylated = Histone regulation

Multiubiquitylated = Endocytosis

Polyubiquitylated = DNA Repair; Degradation

101
Q

What is the tag that directs proteins to lysosome?

What is the tag of ER resident proteins?

A

mannose-6-phosphate

KDEL

102
Q

Functions of Amino Acids

A

a) Proteins
b) Hormones
c) Co-enzymes
d) Nucleotides
e) Alkaloids
f) Cell wall polymers
g) Antibiotics
h) Neurotransmitters

103
Q

Top three molecules by mass in the body

A

Water

Protein

Fat

104
Q

Modifications in amino acids

A

–Hydroxylation (proline, lysine)

–Esterification (serine, threonine, tyrosine) •Acetylation •Phosphorylation

–Disulfide bonds (cysteine → cystine)

–Methylation (lysine, histidine, glutamate)

–Carboxylation (glutamate)

105
Q

10 Essential amino acids

A

These Ten Valuable Amino acids Have Long Preserved Life In Man.

Threonine Tryptophan

Valine Arginine*

Histidine* Leucine

 Phenylalanine  Lysine

Isoleucine Methionine*

(Tryosine can be made from Phenylalanine)

106
Q

Name the

5 carbon ring

6 carbon ring

A

Furanose

Pyranose

107
Q

What type of transport occurs at nuclear porest?

A

Gated transport

108
Q

How do molecules enter nucleus

A

<5kDa diffusion

>60kDa active transport

109
Q

RAN transport

A

Cargo binds to the carrier (Nuclear Import Receptor).

Carrier enters the nucleus, releases protein, and binds to RAN-GTP

Carrier enters cytoplasm and GTP is hydrolyzed and RAN released.

110
Q

NFAT import

(IL2 used during Tcell activation)

A

NFAT is triphosphorylated

High calcium activates calcineurin (protein phosphatase)

NFAT with calcineurin enters nucleus

Gene activation (IL2 transcription)

Low calcium removes calcineurin from NFAT, and NFAT is phosphorylated and exported

111
Q

Three secretory pathways

A

Signal-mediated diversion to lysosomes

Constitutive secretory pathway (e.g. collagen)

Signal-mediated diversion to secretory vessicles (for regulated secretion) (e.g. digestive enzymes)

112
Q

What is the most abundant protein in mammals

A

Collagen

16 types but predominant

113
Q

Collagen structure, assembly

A

Composed of two identical chains (α1) and an additional chain that differs slightly in its chemical composition (α2)

Each chain contains 1050 amino acids

Collagen are translated as longer precurosrs

Co-translational translocation

Default pathway

114
Q

Modifications of collagen in ER and golgi

A

The signal peptide on the N-terminal is dissolved, and the molecule is now known as propeptide (not procollagen).

Hydroxylation of lysines and prolines on propeptide by the enzymes prolyl hydroxylase and lysyl hydroxylase (to produce hydroxyproline and hydroxylysine) occurs to aid crosslinking of the alpha peptides. It is this enzymatic step that requires vitamin C as a cofactor. In scurvy, the lack of hydroxylation of prolines and lysines causes a looser triple helix.

Glycosylation occurs by adding either glucose or galactose monomers onto the hydroxyl groups that were placed onto lysines, but not on prolines. From here the hydroxylated and glycosylated propeptide twists towards the left very tightly and then three propeptides will form a triple helix. This molecule, now known as procollagen (not propeptide) is composed of a twisted portion (center) and two loose ends on either end. At this point the procollagen is packaged into a transfer vesicle destined for the golgi apparatus.

In Golgi,

polymers of sugars are added

115
Q

Largest capacity organ for protein synthesis

A

Pancreas

116
Q

What cell in pancreas produce digestive enzymes?

A

acinar cells

117
Q

Examples of enzymes produced in pancreas

A

Trypsinogens (1, 2, 3)

Chymotrypsinogen (A, B)

α-Amylase

Procarboxypeptidase A (1, 2)

Lipase

Procarboxypeptidase B (1, 2)

DNase

Prophospholipase (I, II)

RNase

Proelastase

Mesotrypsin

118
Q

How genes for digestive enzymes are regulated?

A

The contain pancreas consensus element (PCE)

A transcription factor, PTF-1, present selectively in the exocrine pancreas, binds to this region and is essential for expression of these digestive enzymes.

119
Q

How do digestive enzymes get diverted to secretory vesicles for regulated secretion?

A
  • Creating a transport vesicle involves assembling a protein coat on the cytosolic face of the budding membrane
  • Different protein coats select different cargo
  • ** GTP-binding** proteins control both spatial and temporal aspects of membrane exchange
120
Q

Clathrin coats types

A

trans-Golgi network - transport to lysozomes

trans-Golgi network - storage in secretory vesicles

plasma membrane - receptor-mediated endocytosis

121
Q

Clathrin multimers

A

Triskelions

122
Q

How digestive enzyme exocytosis is regulated?

A

By neurohumoral agents

gastrin-releasing peptide (GRP)

cholecystokinin (CCK)

acetylcholine (Ach)

secretin

vasoactive intestinal polypeptide (VIP)

123
Q

What is the name of the response mediates an adaptive response so that the exocrine pancreas can adjust its machinery to the effects of the stressors and proceed with normal synthetic and transport functions

3 functions

A

unfolded protein response (UPR)

1) chaperones and foldases
2) activate the ERAD
3) global reduction in translation (except for digestive enzymes)

124
Q

quality control system for unusable proteins

A

ER-associated protein degradation (ERAD)

125
Q

Calnexin function

A

Ensures that glycosylated proteins are correctly folded.

126
Q

Describe ERAD

A

Chaperone cannot fold the protein

Protein is feed through channel to cytoplasm

Protein in ubiquitinated

Proteasome degrades protein

127
Q

What is central organ tha regualtes level of cholesterol?

A

Liver

128
Q

LDL function

A

Carries cholesterole

apolipoprotein B100 (part of LDL complex) that binds to LDL receptor and signals removal of LDL from ciruclation

129
Q

Cholesterol function

A

Membrane permeability

Precursor for the biosynthesis of steroid hormones, bile acids, and vitamin D

130
Q

Enzymes in lysozome

A

Nucleases

Proteases

Glycosidases

Lipases

Phosphatases

Sulfatases

Phospholipases

131
Q

3 pathways to degradation in lysozomes

A

Autophagy

Phagocytosis

Endocytosis

132
Q

Types of Coenzymes (Cofactors)

A

Cosubstrate: associates transiently with the active site of an enzyme

Prosthetic group: associates permanently to the active site of an enzyme

133
Q

ATP

energy, energy charge, cation

A

deltaG = -7kcal/mol

Magnesium

Energy charge = ([ATP] + ½ [ADP])/ ([ATP] + [ADP] + [AMP])

134
Q

Enzymes

AMP + ATP <-> ADP + ADP

XMP + ATP <-> XDP + ADP

XDP + ATP <-> XTP + ADP

A

Adenylate kinease

Nucleoside monophosphate kinease

Nucleoside diphosphate kinease

X=A,G,U, or C

135
Q

AH2 + NAD+ –> A + NADH + H+

CH3CH2OH + NAD+ –> CH3CHO + NADH + H+

A

Dehydrogenase

Alcohol denhydrogenase

136
Q

Which part of the CoA is reaction?

A

Sulfhydryl group (-SH)

forms thioester bonds with organic acids

Thioester bond -7kcal/mol

137
Q

What is the function of S-adenosyl methionine

A

To carry methyl groups

Converted to S-adenosyl homocysteine after the methyl transfer

138
Q

Turner Syndrome characteristics

A

Only monosomy compatible with life
Absence of ovaries
Webbed neck
Lymphedema of the extremities
Skeletal deformities
Broad chest
Widely spaced nipples

139
Q

Cri-du-chat Syndrome characteristics

A

Deletion of chromosome #5
cat-like cry
Microcephaly
intelectual disability
congenital heart disease

140
Q

Miller-Dieker syndrome characteristics

A

a condition characterized by a pattern ofabnormal brain development known as lissencephaly. Normally the exterior of the brain (cerebral cortex) is multi-layered with folds and grooves. People with lissencephaly have an abnormally smooth brain with fewer folds and grooves.

141
Q

Angelman’s syndrome

A

Microdeletion on maternal csome15
Intellectual disability
Cannot speak
Exhibit poor motor development
Prone to unprovoked and prolonged period of laughter

142
Q

Prader Willi

A

Microdeletion on paternal csome15
Hypotonia
Obsety
Intellectual disability
Hypogonadism
Undescended testes

143
Q

Ciclosporin

A

Calcinurin inhibitor

Reduces immune response

Block 1 (25 decks)

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