100% tevredenheidsgarantie Direct beschikbaar na betaling Zowel online als in PDF Je zit nergens aan vast
logo-home
Physiology lecture summary €5,49   In winkelwagen

Samenvatting

Physiology lecture summary

 6 keer bekeken  0 keer verkocht

Physiology lecture summary

Voorbeeld 2 van de 9  pagina's

  • 15 april 2022
  • 9
  • 2021/2022
  • Samenvatting
Alle documenten voor dit vak (2)
avatar-seller
annerixtvanderwal
Physiology lecture P1

Eicosanoids synthesis: a role in autocrine signalling, involved in pain, fever and inflammation.

Transmembrane proteins:
- Ion-channel-linked receptor
- G-protein-linked receptor
- Enzyme-linked receptor
Synaptic signalling
Trimeric GTP-binding

Signalling by phosphorylation & signalling by GTP-binding protein
APP = ADP, GPP = GDP
Signal integration, converging of pathways
Downstream signals

Gs couples receptor activation to cAMP formation
cAMP activates A-kinase, which activates phosphorylase kinase, which activates glycogen
phosphorylase, resulting in glycogen conversion to glucose-I-phosphate, i.e. glycolysis.

Calcium homeostasis
Calcium-binding molecules

 25 receptor mediated processes via G-protein-linked receptor and phospholipase-C-
(kringel s), which cleaves PIP2.

C-kinase activation results in gene transcription.
Enzyme-linked cell surface receptors: most receptor for growth and differentiation factors
are transmembrane tyrosine-specific protein kinases.

MAP-kinase(-kinase) (-kinase)
Tyrosine phosphorylation and subsequent SH2 interaction with messenger protein leads to
activation of Ras proteins, all of these reactions are quickly reversed.

Long-lived relays to the nucleus involve multiple cascades of serine/ theonine
phophorylations, esp. performed by the MAP (mitogen-activated protein) kinases (or ERK -
extracellular-signal-regulated kinases)

Epithelium(cell) including glands
Cell adhesion molecules (CAM’s)
1. Cadherins: cell-cell adhesion
2. Selectins: temporary cell-cell connections
3. Integrins: cell-matrix adhesion
4. Immunoglobulin (Ig) – like CAM’s: cell-cell connections
Cadherins form a kind of zipper to bind a cell to a cell, you have different types, they can
steer the faith of cells by themselves.
Selectins are important in adhesion of leukocytes during inflammatory processes.

, Endothelium lines our blood vessels.
Weak adhesion and rolling (selectin-dependent) & strong adhesion and emigration (integrin-
dependent).

Adhesion to the extracellular matrix is achieved through integrins (focal adhesions).
IG-like adhesion molecules also can connect cells to each other.
Epithelium forms an interconnected layer due to cell-cell connections and the cell-matrix
connections.

Gap junctions allow the passage of small water-soluble molecules from cell to cell.

Cell connecting structures
1. Adhesion structures: attachment between cells or between cells and matrix
- Intermediate filaments, desmosomes or macula adherens hemidesmosomes
- Microfilaments actin filaments, zonula adherens (band shaped), adhesion plates (also
called focal adhesions)
- Adhesion of cells to cells or matrix are mediated by anchor proteins which serve to
couple the CAM’s to intracellular filaments.
- Zonula adherens uses cadherins to connect the cells and connects to actin filaments.
2. Occludens connections: closing connections, seal of the cell layer -> tight junction
(zonula occludens) (closes the space between two cells)
- passage of molecules occurs through the cytoplasm of the epithelial cell.
3. Communication connections: communication among cells
- Synapses (muscle – nerve cell, nerve cells)
- Nexus connections (gap junctions)
Lamina basalis and basal membrane
Lamina basalis
- Extracellular, presents the border between connective tissue and other tissue types.
- Function is adhesion and sieve/ filter
- EM: lamina densa (dark, collagen type 4 and proteoglycans), flanked by lamina lucida
on both sides (brighter, laminin)
- Lamina basalis consists of type 4 collagen, with glycoproteins such as laminin to
which cells can bind.
- The lamina basalis can be found everywhere where connective tissue connects with
other tissues
Basal membrane
- Lamina basalis + dense collagen layer with glycoproteins (= lamina reticularis) directly
layered against lamina basalis can be observed in LM.

Functions of epithelia
Multi layered epithelia:
- Protect against friction and injury
- Barrier to water, disease some toxins, etc.
- Lower layers regenerate upper layers
Single layered epithelia:
- Communication/ gateway
- Important in regulated transport of cells/ molecules

Voordelen van het kopen van samenvattingen bij Stuvia op een rij:

Verzekerd van kwaliteit door reviews

Verzekerd van kwaliteit door reviews

Stuvia-klanten hebben meer dan 700.000 samenvattingen beoordeeld. Zo weet je zeker dat je de beste documenten koopt!

Snel en makkelijk kopen

Snel en makkelijk kopen

Je betaalt supersnel en eenmalig met iDeal, creditcard of Stuvia-tegoed voor de samenvatting. Zonder lidmaatschap.

Focus op de essentie

Focus op de essentie

Samenvattingen worden geschreven voor en door anderen. Daarom zijn de samenvattingen altijd betrouwbaar en actueel. Zo kom je snel tot de kern!

Veelgestelde vragen

Wat krijg ik als ik dit document koop?

Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.

Tevredenheidsgarantie: hoe werkt dat?

Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.

Van wie koop ik deze samenvatting?

Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper annerixtvanderwal. Stuvia faciliteert de betaling aan de verkoper.

Zit ik meteen vast aan een abonnement?

Nee, je koopt alleen deze samenvatting voor €5,49. Je zit daarna nergens aan vast.

Is Stuvia te vertrouwen?

4,6 sterren op Google & Trustpilot (+1000 reviews)

Afgelopen 30 dagen zijn er 67474 samenvattingen verkocht

Opgericht in 2010, al 14 jaar dé plek om samenvattingen te kopen

Start met verkopen
€5,49
  • (0)
  Kopen