Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Genetics > Lecture 8 - Genetics of Biologic Processes > Flashcards

Lecture 8 - Genetics of Biologic Processes Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Developmental Process - General

A

-initially there is ecto/endo/meso-derm
-Conrad said -> developing embryo represented as an
EPIGENTIC LANDSCAPE
-a landscare as a series of valleys which cell may pass as it differentiates toward final tissue type (toti->pluri->monopotent)

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

iPS

A

-Induced Pluripotent Stem Cells:

> > Somatic cells can be reprogrammed to take different path of differentiation

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

Totipotent

A
  • stem cell of the fertilized egg
  • can give rise to any cell/entire organism
  • lasts 4 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pluripotent

A
  • Stem cell that can give rise to any cell

- Cannot give rise to an entire organism

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

Multipotent

A

-more differentiated stem cell that give to rise to progenitors of cell lines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Naive Multipotent Cell and what are the types

A

Naive Multipotent cell –> Commited to it’s cell line

Specialized State:
-> reversible

Determined State:
-> Irreverisble

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

Cell Differentiation is based on

A

1) INTRINSIC:
- Lineage

2) EXTRINSIC:
- Positional identity (influenced by -> morphagens/cell:cell interaction/Cell:Matrix Interaction)

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

Morphagen

A
  • soluble signalling molecule

- depending on their conc grad -> exert diff effect on their target cells

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

Example of Morphagen Genes

A

1) Maternal Effect Genes: - expressed in other during oogeneis + acts on mature oocyte
2) Gap Genes/Pair Rule Genes: - acting on fertilized egg to cause segmentation
3) Homeotic Genes: - regulate segment identity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Specific Example of a Morphagen

A

Morphogen Activin (TGF-B):

  • mesoderm differentiation is affected
  • 0.1ng/ml -> blood like cells
  • 100ng/ml -> heart cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Sonic Hedgehog Gene

A
  • produced Morphogen -> SHP

- expressed in Notochord + Central Cells of Ventral Neural Tube

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

What does Sonic Hedgehog protein do

A
  • Develop of CNS + MUSCLE + LIMBS
  • lateralization process

small amt of SHP in Dorsal tube -> Sensory Neuron
-Lg amt of SHP in Ventral -> Motor Neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Homeotic (HOX) genes

A
  • all have similiar 60-codon long homeobox seq
  • master regulator gene -> reg expression of other gene
  • encode TF
  • it’s expression affected by Morphagen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens when HOX is mutated

A

-one part of body becomes phenotypically similar to another disimilar part

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

SRY gene

A
  • Sex Determining Region on Y-chromosome –> Determines maleness
  • Architectural TF –> binds + bends DNA –> regulates expression of certain genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Sertolli + Leydig Cells

A

!!Sertoli cells!! –> Anti-mullerian hormone –> inhibits Female Diff

!!Leydig cells!! –> Test –> Male sex diff

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Mechanism of SRY

A

SRY –> incr SOX9 –> FGF9 –> amplifies SOX9

When SOX9 reches appreciable level –> bipotential cells begin to differ into Sertoli cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Female Sexual Differentiation

A

RSPO1 + Wnt4 –> act Synergetically

in absence of SRY -> act on bipotential cells –> female differentiation

19
Q

SEX REVERSION

A

-point mut or deletion of SRY –> creates phenotypic Females

20
Q

Factors causing Developmental Abnormality

A
  1. Tetratogens
  2. Chromosome Imbalance
  3. Complex Inheritance
  4. Single Gene Mutation
21
Q

Disorders of HOX gene

A

-mut in HOX gene can cause mild symptoms or life threatening

22
Q

HOXD mutation

A

-Syndactyly (fused digits) + Polydactyly (extra digits)

23
Q

HOXA mutation

A

-Hand-Foot-Genitals Syndrome

24
Q

Chromosome Imbalance examples

A
  • Patau
  • Turner
  • Fetal Hydrops
25
Q

Classification of Tetratogens

A

1) Synteratogen
- needs to combine with another for effect (lead, cadmium)

2) Proteratogen:
- not effective until metabolised

26
Q

Effect dependence of Teratogens

A

-Dose
-Sensitivity
> genetic background
> developmental period

27
Q

Examples of Teratogens

A

1) Drugs/Chemical: lead/cadmium/coke/mercury
2) Infect. Agens: TORCH
3) Ionizing Radiation
4) Maternal Metabolism Factors: DM/PKU/Starvation

28
Q

DES

A

-synthetic Estrogen –> used prophylactically to prevent Miscarriage + Abortion

CAUSES:

  • > vaginal tumours in child
  • > ectopic preg
  • > T-shaped uterus
29
Q

Oncogenetics - General

A
  • 40% chance of developing some form of cancer in our lifetime
  • tumours are only 10% affected by inheritance but genotype does affect our overall risk

-oncogenics is stepwise –> accumulation of somatic mutations

30
Q

Most common Mutating genes in Oncogenetics

A
  1. Oncogenic:
    - dominant mutations
    - gain of function mutation
  2. TSG:
    - recessive mutation
    - loss of function mutation
  3. Mutator Gene:
    - genes of DNA repair
    - rate of germline/somatic mut increase when theese affeted
31
Q

Inherited Oncogenes

A

Inherited mutation of RET Gene:

  • MEN2A
  • FMTC

Inherited mutation of RAS Gene:
- Myeloid Leukemia

32
Q

Mechanisms that oncogenes can be activated

A

1) Double Minute Chromosomes
2) Point Mutation
3) Translocation
4) Retrovirus Encoded Promotor/Enhancer
5) Oncogene Hypomethylation

33
Q

Double Minute Chromosome

A
  • small fragments of circular extrachromosomal DNA

- manifest during abnormal gene amplification –> give tumour cells advantage to survive

34
Q

Point Mutation in Oncogenes

A

RAS (p21):
- RAS codes for G protein
- mut in H-RAS –> decr Hydrolysis of activated RAS –>
cellular proliferation

35
Q

Translocation in Oncogenes

A

Philadephilia Chromosome

36
Q

Retrovirus Encoded Promotor/Exchanger

A

-infection carriers these enhancers to oncogene –> overexpression

37
Q

Oncogene Hypomethylation

A

IN LIVER TUMOURS:

-promotor of N-RAS is hypomethylated

38
Q

TSG Mechanism of Cancer

A

-loss of Hetereozygoity (2 hit hypothesis)

39
Q

Common TSF

A

-p53 + RB

40
Q

Epigenetics relation to TSG and cancer

A

-hypermethylation -> inhbits

41
Q

Most cancers are

A

MULTIFACTORIAL PROCESS

42
Q

Environmental factors and Cancer

A

-environmental factors may not cause mutation but still cause cancer

HPV: proteins bind to RB + P53

43
Q

Somatic Gene Re-arrangement (VDJ)

A
  • VJ = Light chain

- VDJ = Heavy chain

Genetics (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions