Pre-gastrulation Flashcards
process by wherein the developmental trajectory of a tissue or organ is affected by the presence of a neighboring group of cells
cellular induction
t or f: cellular induction usually results in changes in gene expression and cell behavior
t
t or f: cellular induction involves signals that bind to receptors to begin the signal transduction pathway
t
it is the ability of a cell to respond to induction
competence
it is the ability to sense and respond to chemical signals
competence
it is the ability of a cell to respond to external factors
competence
t or f: before a responder can respond, it should be competent
t
t or f: morphogens act over short distances
f; long
how do different tissues respond to a signal
- incompetent
- competent and correct
- competent and incorrect
induction may either be: (types of induction)
permissive and instructive
a type of induction wherein the responder contains all the potentials that are to be expressed, and needs only an environment that allows the expression of these traits
permissive interaction
a type of induction wherein a signal from the inducing cell is necessary for initiating new gene expression in the responding cell
instructive interaction
two types of instructive interaction
- appositional
- morphogen gradient
it is an instructive interaction wherein there must be a close interaction with the tissues to allow the expression to happen
appositional interaction
what are the types of cell-to-cell communications?
- autocrine
- signaling across gap junctions
- paracrine
- endocrine
a form of chemical signaling wherein a cell targets itself
autocrine
a form of chemical signaling wherein a cell targets a cell connected by gap junctions
signaling across gap junctions
a form of chemical signaling wherein a cell targets a nearby cell
paracrine
a form of chemical signaling wherein a cell targets a distant cell thru the bloodstream
endocrine
t or f: in the signal transduction pathway, the chemical messengers can only enter the target cell via diffusion
f; it can enter via receptor binding as well
t or f: the nature of the ligand cannot affect the type of signal transduction
f
which chemical signaling is considered long lasting
endocrine
which chemical signaling is considered short-lasting
paracrine
t or f: an H2O ligand can diffuse into the membrane
f
t or f: a fat-soluble ligand can diffuse into the membrane
t
it is the transmission of molecular signals from the cell’s exterior to its interior and is also known as cell signaling
signal transduction
what happens to fat-soluble ligand when it enters the cell?
there is an intracellular binding of receptor
t or f: cell-to-cell interactions does not need an environment to initiate responses
f
t or f: the ECM is a homogenous structure
f
different components of the ECM
- proteoglycans
- fibronectin
- laminin
structure that supports the tissue and cell
ECM
t or f: if tissue shape changes, ECM changes
t
example of developmental stage wherein ECM is helping
neural fold formation; ECM needs to change to raise the neural plate
multiple functional roles of the ECM in various biological processes
- functions as adhesive substrate
- provides structure
- presents growth factors to their receptors
- sequesters and stores growth factors
- senses and transduces mechanical signals
an ECM component that is responsible for the delivery of paracrine factors
proteoglycans
pathway involved in heparan sulfate, a proteoglycan
FGF pathway
t or f: if proteoglycan synthesis is blocked, normal cell migration, morphogenesis, and differentiation will still take place
f
two examples of proteoglycans
heparan sulfate and chondroitin sulfate
a glycoprotein which serves as a general adhesive molecule
fibronectin
a glycoprotein which paves the roadway
fibronectin