PSIO 305 Exam 2 UPDATED ACTUAL Questions And Correct Answers
C
Terms in this set (152)
Blastula Ectoderm
Mesoderm
Endoderm
Ectoderm outermost layer
helps form neural and epithelial tissue
Mesoderm middle layer
helps form skeletal muscle, connective, dermis of skin, urogenital and
cardiovascular system
Endoderm innermost layer
helps form other internal organs
Stages of Neural Development Determination
Proliferation
Differentiation
Migration
Axon Elongation
Synapse Formation
Synapse Rearrangement
Determination (Neural) cell is committed/determined to a fate (irreversible)
how do specific omnipotent cells determine themselves to become specific
neural tissue?
mesoderm releases specific factors important to determination of neural
precursor cells becoming neurons
Induction Process determination of tissue to be epidermal or neural tissue
mesoderm secretes diffusible factors that facilitate determination or induction of
small number of ectodermal cells to become neural cells; remaining cells
become epidermal
Ectoderm Culture Experiment animal cap (ectoderm) removed and cultured (nutrients + saline)
--> epidermis
animal cap (ectoderm) + mesoderm (Spemann organizer) cultured --> nervous
tissue
cells of ectoderm (dissociated; not in animal cap) added together --> neural tissue
- suggests there are neural inhibitors
- BMP4 bound to ectoderm = skin
- Spemann organizer releases neural inducers --> ectoderm cannot bind BMP4 -->
neural tissue
, Spemann Organizer generates neural inducers
Noggin - forms head
Chordin - forms spinal cord
Cerberus - forms head
Follistatin - forms follicles
Neural Inhibitors bone morphogenic proteins (BMPs)
Bone Morphogenic Proteins (BMPs) aka cytokines
member of transforming growth factor (TGFβ) family
clipped to active form
form dimers and secreted
only about 20 known
bind to BMP receptors (extracellular)
Signaling Pathway for BMPs
Signaling Pathway for BMPs bind to BMPR (protein kinase)
phosphorylates self and Smad 1 (ferrying cytoplasmic protein)
Smad 1 binds to Smad 4 --> Smad 1/Smad 4 complex
Smad 1/Smad 4 complex enters nucleus and affects transcription factors
--> turn on epidermal genes
--> turn off neural genes
Inducers
Signaling Pathway for BMPs (Inducers) BMP inhibited (intercepted) by neural inducers
prevent binding to BMPR
no activation of Smad pathway
neural genes activated
neural-specific proteins produced
*can be blocked using a neural inhibitor
Proliferation (Neural) rapid mitotic cell division
how proliferation occurs and what growth factors are responsible?
V. Hamburger Experiment in a chick, number of neurons peaked in 1st quarter of gestation, then declined
nervous system over-proliferates because neurons do not grow via mitosis (set
number for life)
any neurons without contact (are nonfunctional) die off
extra limb transplanted on chick --> number of neurons did not decline as much
*target is essential for the survival of neurons
Growth Factor Experiment Cell Culture 1 - Control
- cells are isolated and treated with saline + nutrients
- cells maintained survival, but did not proliferate
Cell Culture 2 - Bovine Serum (contain proliferation factors)
- cells are isolated and treated with saline + Bovine Serum
- proliferation increased (number of cells increased)
- proliferation rate proportional to serum concentration
Cell Culture 3 - Serum to no Serum
- cells are isolated and treated with Bovine Serum initially, then moved to a dish
with no serum
- proliferative effects of serum decreased (number of cells decreased)
*growth factors (GFs) are soluble (substance in serum is used up)
C
Terms in this set (152)
Blastula Ectoderm
Mesoderm
Endoderm
Ectoderm outermost layer
helps form neural and epithelial tissue
Mesoderm middle layer
helps form skeletal muscle, connective, dermis of skin, urogenital and
cardiovascular system
Endoderm innermost layer
helps form other internal organs
Stages of Neural Development Determination
Proliferation
Differentiation
Migration
Axon Elongation
Synapse Formation
Synapse Rearrangement
Determination (Neural) cell is committed/determined to a fate (irreversible)
how do specific omnipotent cells determine themselves to become specific
neural tissue?
mesoderm releases specific factors important to determination of neural
precursor cells becoming neurons
Induction Process determination of tissue to be epidermal or neural tissue
mesoderm secretes diffusible factors that facilitate determination or induction of
small number of ectodermal cells to become neural cells; remaining cells
become epidermal
Ectoderm Culture Experiment animal cap (ectoderm) removed and cultured (nutrients + saline)
--> epidermis
animal cap (ectoderm) + mesoderm (Spemann organizer) cultured --> nervous
tissue
cells of ectoderm (dissociated; not in animal cap) added together --> neural tissue
- suggests there are neural inhibitors
- BMP4 bound to ectoderm = skin
- Spemann organizer releases neural inducers --> ectoderm cannot bind BMP4 -->
neural tissue
, Spemann Organizer generates neural inducers
Noggin - forms head
Chordin - forms spinal cord
Cerberus - forms head
Follistatin - forms follicles
Neural Inhibitors bone morphogenic proteins (BMPs)
Bone Morphogenic Proteins (BMPs) aka cytokines
member of transforming growth factor (TGFβ) family
clipped to active form
form dimers and secreted
only about 20 known
bind to BMP receptors (extracellular)
Signaling Pathway for BMPs
Signaling Pathway for BMPs bind to BMPR (protein kinase)
phosphorylates self and Smad 1 (ferrying cytoplasmic protein)
Smad 1 binds to Smad 4 --> Smad 1/Smad 4 complex
Smad 1/Smad 4 complex enters nucleus and affects transcription factors
--> turn on epidermal genes
--> turn off neural genes
Inducers
Signaling Pathway for BMPs (Inducers) BMP inhibited (intercepted) by neural inducers
prevent binding to BMPR
no activation of Smad pathway
neural genes activated
neural-specific proteins produced
*can be blocked using a neural inhibitor
Proliferation (Neural) rapid mitotic cell division
how proliferation occurs and what growth factors are responsible?
V. Hamburger Experiment in a chick, number of neurons peaked in 1st quarter of gestation, then declined
nervous system over-proliferates because neurons do not grow via mitosis (set
number for life)
any neurons without contact (are nonfunctional) die off
extra limb transplanted on chick --> number of neurons did not decline as much
*target is essential for the survival of neurons
Growth Factor Experiment Cell Culture 1 - Control
- cells are isolated and treated with saline + nutrients
- cells maintained survival, but did not proliferate
Cell Culture 2 - Bovine Serum (contain proliferation factors)
- cells are isolated and treated with saline + Bovine Serum
- proliferation increased (number of cells increased)
- proliferation rate proportional to serum concentration
Cell Culture 3 - Serum to no Serum
- cells are isolated and treated with Bovine Serum initially, then moved to a dish
with no serum
- proliferative effects of serum decreased (number of cells decreased)
*growth factors (GFs) are soluble (substance in serum is used up)
