Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

genetics concepts > Exam 2 concepts > Flashcards

Exam 2 concepts Flashcards

1
Q

what are some of the factors that can influence birth defects in childhood?

A
  1. multifactorial
  2. unknown
  3. teratogens
  4. monogenic
  5. chromosomal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the classification classes of birth defects

A
  1. malformation
  2. disruption
  3. deformation
  4. dysplasia
  5. sequence
  6. syndrome
  7. association
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are some traits associated with cardiac defects

A
  • major cause of death in first year of life
  • common anomaly is ventricular septal defects
  • incidence is 5-8 per 1000 births
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are some of the developmental milestones as it pertains to neural tubes?

A

18th day-neural plate developmental
24th day-cranial closure
26th day-caudal closure

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

what are the different spina bifida degrees?

A
  1. spina bifida occulta
  2. lipomeningocele
  3. meningocele
  4. myelomeningocele
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

in the last decade, what has folic acid/vitamin b0 been used for?

A

for prevention of neural tube defects (NTD), coronary artery disease (CAD), stroke and colorectal and cervical cancer

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

polymorphisms in folate metabolism enzyme encoding genes can result in what?

A

risk factors for neural tube defects. the enzymes are responsible for recycling of folate

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

what are the fetus malformations that are results of using thalidomide?

A

amelia, phocomelia, hypoplasia and absence of some bones

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

what are the immunomodulatory properties of thalidomide therapeutic properties?

A 
Inhibition and stimulation of cytokines
Co-stimulation of primary human T cells
Modification of surface cell adhesion molecules
Induction of NK cells
Treats leprosy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the non immunomodulatory properties of thalidomide therapeutic properties?

A

Anti-angiogenic activity
Anti-proliferative and pro-apoptotic activity
Treats cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the potter sequence?

A

urethral agenesis–> oligohydramnio–> fetal compression in utero, growth deficiency, multiple malformations, altered facies, limb positioning defects

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

what are some other health problems that down syndrome could increase the chance of?

A
  • heart defects
  • thyroid disease
  • nearsightedness
  • farsightedness
  • alzheimers
  • leukemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are some of the personality problems with Fetal alcohol syndrome

A

Difficulty with time
Being where they should be on time
Problems managing money
Difficulty transferring learning to other situations
Difficulty determining what to do in a given situation

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

what does VATER stand for?

A

V - Vertebrae problems,
For example, abnormally formed vertebrae, and extra ribs.
A - Anal Anomalies and sometimes rectum problems.
For example, there is no opening where the anus should be
T - Trachea problems.
For example, there is a connection between the trachea and esophagus.
E - Esophagus problems.
For example, part of the esophagus is missing.
R - Radius (lower arm bone) problems
For example, the larger lower arm bone is abnormally formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what factors influence teratogenicity?

A 
Dose
Route
Frequency of exposure
Duration of exposure
Concurrent exposures
Concurrent illness
Genetic susceptibility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the teratogenesis mechanisms

A
  1. Mutation
  2. Chromosomal aberrations
  3. Mitotic interference
  4. Nucleic acid metabolism alteration
  5. Energy metabolism interference
    - substrate deficiency
    - pathway inhibition
  6. Cell membrane alterations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the developmental gene families?

A 
homeobox (hox) gene family
Paired box (pax) gene family
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the developmental gene pathways?

A

Fibroblast growth factor and receptors
Sonic hedgehog pathway
Neural crest cell migration network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the explanations for an important gene family produces only 3 rare human syndromes?

A

One HOX gene may be able to compensate for deficiency in another (redundancy)

HOX genes are so important that when mutated inevitably produces early pregnancy loss (no viable babies born)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the treatment for aniridia?

A

colored eye lenses in order to reduce the light inlet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the cell signals used to organize itself into embryonic tissues

A

juxtracine signal and paracrine factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the examples of signals used for sonic hedgehog pathway?

A

to differentiate, die, and migrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are the two ways shh does its signals?

A 
-signals 
to adjacent cells
when tethered 
to the plasma
membrane
-signals 
in long range 
as freely 
diffusible molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are the symptom ranges of holoprosencephaly?

A 
mild (anosmia, or a single central incisor) 
to moderate (cleft lip or palate) 
to severe (cyclopia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
HH signaling is linked to an increasing number of what?
cancers, can be cancers with mutations in the HH pathway or cancers with autocrine requirements for HH ligand
26
what are the 4 types of waardenburg syndrome?
type 1: hearing loss and white forelock type 2: very similar to type 1 type 3: severe form with limb abnormalities type 4: waardenburg and hirschprung
27
why does loss of melanocytes lead to deafness?
melanocytes produce endolymph in the stria vascularis. stria vascularis uses that endolymph for the scala media where the organ of corti is. Organ of corti contain auditory sensory cells
28
what are the mutations associated with male pseudohermaphroditism?
SF1 mutation, SOX9 mutation, and WT1 mutation
29
Any factor raising testosteron level will serve as SRY surrogate and will lead to what?
masculinization of female genitalia (Female pseudohermaphroditism)
30
what are the factors raising testosterone levels in females?
A) Maternal androgen ingestion (exogenous) | B) 21-hydroxylase deficiency enzyme deficiency
31
what phase does the genome work to express genes
g1 and g2
32
what is the ploidy for sperm and eggs vs somatic cells
sperm and eggs are haploid and somatic cells are diploid
33
what can be the result of changes in the chromosome number and structure
``` birth defects, mental retardation, infertility, miscarriage cancer ```
34
what does chromosome morphology depend on
the position of the centromere
35
what are the methods of chromosome analysis
1. chromosomal banding 2. FISH (fluorescent in situ hybridization) 3. CHG (comparative genome hybridization)
36
how does FISH work
fluorescent labeled DNA probe anneals to DNA within the metaphase chromosomes by its complimentarity . Then can confirm if a baby has a certain disease
37
what is SKY useful in?
in identifying complex karyotypes especially in cancer
38
individual chromosomes territories are what
tissue specific
39
the relative positions of chromosomes in an interphase nucleus depend on what
the proportion of genes and the A+T content
40
how does CGH work?
1. mix patients dna with normal dna 2. put the mixed solution on a metaphase spread and and with the rest of solution array pieces of genomic dna 3. for the spread and array red sections mean gain so duplication. Green means loss which is deletion
41
subtelomeric chromosome rearrangements are common in whom
kids with idiopathic mental retardation
42
when does crossing over occur
during prophase I of meiosis (pachytene) in a process called synapsis within synaptonemal complexes
43
what is dicytyotene
when Ova arrested for 10-50 years | in Meiotic prophase I (at birth)
44
what does long waiting in dictyotene do
leads to increased probability of non disjunction of chromosomes
45
The relative frequency of new autosomal dominant mutations in children increases logarithmically with what?
paternal age
46
what is 2 paternal and 1 maternal called
triploid, large placenta, very small fetus
47
what is the result of 2 maternal and 1 paternal
triploid, some live through 2nd trimester, very rarely to term intrauterine growth retardation
48
what does monosomy lead to
miscarriages
49
what does trisomy lead to
``` patau syndrome (+13) edwards syndrome (+18) down syndrome (+21) and miscarriages ```
50
what are structural abnormalities of chromosomes caused by
translocations deletions and insertions inversions
51
what does the clinical outcome of structural abnormalities depend on
the net gain of loss of chromosome material
52
what is the net effect of robertsonian translocations
no changes in gene expression on q-arms; Loss of rRNA expression, Cell will not feel the loss phenotypically due to rRNA gene redundancy
53
what are some other traits of robertsonian translocation
- example of balanced abnormality - abnormal karyotype - hybrid mini chromosome
54
balanced abnormalities may lead to what
unbalanced abnormality in the offspring
55
As with all chromosome abnormalities, chromosomal inversions and rings problems depends on what
what is found, size of the ring, how much material was lost, which chromosomes are involved
56
what kinds of chromosomes are always lost in mitosis
acentric and dicentric
57
what are the two kinds of chromosomal abnormalities
1. balanced, no net gain or loss of chromosomal material. Translocation and inversions. 2. unbalanced, net gains and loss. deletions and insertions
58
phenotypes are not produced in balanced chromosomal abnormalities except in what cases?
- chromosomal break disrupts important gene | - break separate gene from regulatory element
59
robertsonian translocations are always what
unbalanced, as small acrocentric fragment is lost
60
what happens if a chromosomal translocation happens in a somatic cell?
cancer
61
what enlarges a telomere
telomerase, a reverse transcriptase, extends the lagging dna strand
62
what are the reasons for tumor development being a complex process?
A multitude of events (greater than 4) Each event has low probability, requires years for full phenotype to develop Mut events happen in succession of each other Because of that cancer is typically a disease of old age
63
what are the steps to genome change
- point mutations - chromosomal rearrangements - changes in methylation pattern - regulatory changes in gene expression
64
what are the gene involved in tumor development
- tumor suppressors - oncogenes - lots of genes that have marginal influence on tumor growth - lots of genes that change their status as consequence of malignization
65
are oncogenes or tumor supressors dominantly inherited?
oncogenes are dominantly inherited (one defective allele can predispose the cell to tumor formation) and tumor suppressors are recessive(Mutation in one allele predispose human to cancer, but do not cause it)
66
how do tumor suppressor genes act in recessive fashion?
If one copy is gone/mutated, second normal allele will function. If both copies are gone/mutated, cancer can progress (two hit hypothesis). Replace a single normal copy and cells return to normal (cell fusion assay).
67
what are the ways oncogenes influence status changing?
- activating point mutations - translocating under strong promoter - amplificiation - overexpression
68
what are the ways tumor suppressors influence status changing
- inactivating point mutations - promoter methylation - gross chromosomal deletion - under expression
69
what are the two alternative statements describing tumors?
- tumors are clonal | - tumor is a mix of different cell populations (tumors are heterogenous)
70
what are some traits towards the claim that darwinian selection is in tumors
-tumor can quickly react to changes in environment (like to treatment of patient with drug or radiation) -Tumor reacts via expanding of pre-existing population of resistant cells or by rapid divisions with producing of multiple clones. 99% of them non viable, but 1% is enough to win a game
71
what are the two main ideas about metastasis?
1. needs many steps and any step is rate limiting | 2. cancer cells should profoundly changes their behavior to get an ability to spread through the organism
72
what is the sequence of metastatic events
``` Genesis of new vasculature (angiogenesis) Detachment of tumor cell from other cells Invasation (entry to vessel) Evasion of natural host defences Arrest in small vessels Attachment to vessel walls Extravasation Establishment of a new growing colony ```
73
what is step 1 of metastasis?
Neovascularisation (neoangiogenesis), Every microtumors >1-2 mm in size need to grow new vessels to escape from hypoxia
74
what does the tumor secrete during step 1 of neovascularization
pro-angiogenic factors as VEGF, FGFs, IL-8, prostaglandins
75
what is step 2 of metastasis
detachment of tumor cells from neighboring cells. Also playing role in the primary tumor invasiveness.
76
what is step 3 of metastasis
entry of tumor cells to vessel,
77
what is step 4 of metastasis
``` evasion of natural host defenses, Because cancer cells are altered-self cells, one would expect cancerous cells to elicit a cell-mediated response ```
78
what are steps 4-7 of metastasis
Arrest in small vesselsand attachment to vessel walls. Extravasation.Establishment of a new growing colony

genetics concepts (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions