M2 3-4 Membranas Flashcards
how is the lamella mediana formed?
it is the first layer formed when the cell undergoes cytokinesis(when the cell divides into two daughter cells)
o canal de Reticulo endoplasmico no plasmodesmata e chamada
Desmotubule
os caracteristicos de GAGs
(Part of the connective tissue in the skin)
-rigida
-hidrofilica
-retem muita agua
composicao de acido hialuronico
acido glucuronico
N-acetil-glucosamina
Nao tem componente proteica
how does hyaluronic acid retain a lot of water?
it does this because of its high density of negative charges, which attracts possitive charges like Na+
what is the order of the types of junction between two cells
TADG- Tadpole gut
T-tight junctions
A- adherens junction
D- desmosome
G- gap junction
what are the types of junction between the cell and the basal lamina
-actin-linked
-hemidesmosome
what is the channel forming junction in the cells called?
Gap junctions
what are the non-classical cadherin proteins?
Desmoglein & Desmocollin
In Desmosome, what is the attachment order?
IN DA CARD
Intermediate filaments(in cell A)–desmoplakin–Adaptor proteins–Nonclassical cadherin proteins
what are the adaptor proteins called?
plakgo, plakfill
Plakglobin& plakophilin
what is the order of junction in the hemidesmossomes
Intermediate filament–intracellular adaptor protein-integrinas-extracellular adaptor protein-collagen
what makes up the tight junctions?
Sealing strands made up of oculin and claudin
role of tight junctions
act as diffusion barrier
isolate the cell to have only two passage ways of transport
what makes up the gap junction
two connexons on each cell’s plasma membrane
what kind of molecules does the gap juncionts NOT pass?
macromolecules
what kind of molecules pass through the gap junctions?
ioes e pequenas moleculas
what are the types of signals a cell can respond to?
Physical, mechanical, neurotransmitter, nutrients, ordorants, pheromones
a cell depends on it’s different types of signals to survive
V ou falso e explicar
Verdarde
Because each of these signals like, growth, differentiate, survive(when antigens hit the cell); are made for the cell’s adaptability and without any signal, the cell will just die
what differentiates the different forms of cell signaling
The speed and selectivity by which the signals are delivered to their targets
when the signal molecule is linked to the receptor what happens?
there’s a conformational alteration that transmits information into the cell, not the signal molecule
order the quickness of a cell to a signal from very fast to slow
-cell movement
-metabolism
-synaptic response
-synthesis of new proteins
-Synaptic response
-metabolism
-cell movement
-synthesis of new proteins
all cells respond to any signal
True or false
False
Not all cells respond
the same signal has to give the same response in different types of cells.
True or false
False
The same signal can instigate a different response in different cells
how is GTP changed to GDP in g proteins?
by guanine nucleotide exchange factors
G-proteins
deactivate themselves with GTPase?
Yes
In cell signalling, GAP(GTPase activating protein) and GEF(guanine nucleotide exchange factors) does what?
GEFs turn on the signal
while
GAP turns off the signal
In G proteins, how are the subunits linked?
By covalent bond to the lipids in the membrane
In G proteins, the cells are always activated by Protein cinases and deactivated by phosphatases?
False
The opposite can happen(activated by dephosphorylation and deactivated by phosphorylation (protein cinase)
what type of responses do the GPCR mediate?
Respostas a sinais de outras celulas (tipo hormonas e neurotransmissores) e a maioria ao ambiente externo (visao, olfato)
The GPCR molecule can catalyze the activation of many G protein molecules
True
