The Cellular Highway
Top "Notch"
Live and Let Die
ECM and Stem Cells
Cell Biology Potpourri
100

COP I mediates vesicular transport in what direction in a cell?

What is retrograde?

100

Binding of a hormone to a receptor tyrosine kinase causes dimerization of the receptor followed by receptor activation through what chemical modification?

What is autophosphorylation?

100

What class of protein is a substrate for polyubiquitination by the APC/C?


What is a cyclin?

100

Gap junctions are composed of what protein?

What are connexins?

100

What biological "factor" catalyzes the dissociation of GDP on the G-protein and promote the replacement of GTP on a GTPase molecular switch?

What is a guanine nucleotide exchange factor?

200

COP II mediates vesicular transport in what direction in a cell?

What is anterorgade?

200

In paracrine signaling, the signaling molecule acts on: the cell that secreted it, cells in close proximity, or cells far away?

What are cells in close proximity?

200

What is the cell cycle checkpoint in mitosis?

What is the spindle-assembly checkpoint?

200

Integrins are activated upon binding to ECM molecules. What cytosolic protein facilitates this activation and downstream signaling?

What is talin?

200

What molecule will pass through a cell membrane the easiest; a sodium ion, glucose, CO2, or lysine?

What is CO2?

300

Clathrin mediates vesicular transport from what organelle to the endosome?

What is the trans golgi network?

300
Activation of cell signaling pathways always leads increases in second messengers that pass along the signal to induce a function in a cell. What is one example of a second messenger?

What is cAMP? (or cGMP, PKC, IP3)

300

Loss of function mutations in what type of pro-apoptotic signaling molecule might be found in a cancer cell?

What is Bax?

300

The basil lamina is composed of what primary ECM molecules?

What are laminn, collagen IV, perlecan, and nidogen?

300

What is the weakest form of non-covalent interactions that can be found in biology?

What are van der Waals interactions?

400

In the endoplasmic reticulum, what modification is added to newly formed proteins to allow them to be packaged into transport vesicles and sent to the Golgi?

What is N-linked glycosylation?

400

During receptor-mediated endocytosis, what change in the endocytic vesicle stimulates release of the ligand from the receptor?

What is a decrease in ph?

400

During apoptosis, what is considered the point of no return where a cell must undergo programmed cell death?

What is cleavage or activation of caspases?
400

The extracellular matrix provides 2 types of cues to regulate cell identity and function, what are those cues?

What are biochemical and mechanical cues?

400

A new drug is developed which selectively cleaves covalent bonds between two sulfur atoms of non-adjacent amino acids in a polypeptide chain. Which level of protein structure in affected molecules would be most directly affected by the drug?

What is tertiary structure?

500

The mannose-6-phosphate receptor packages cargo into transport vesicles destined for the lysosome. Where does this cargo end up if the Golgi lacks the mannose-6-phosphate receptor?

What is the extracellular space?

500

Notch is a cell surface receptor engaged by a transmembrane protein (called Delta) in the membrane of a neighboring cell. What event in the cytosol transmits the signal from delta binding to the Notch receptor?

What is proteolytic cleavage of the cytosolic tail?

500

Cell murder occurs when what ligand is activated by immune cells?

What is the Fas receptor?

500

What genes are responsible for maintaining stemness in stem cells?

What are Oct4, Sox2, and Nanog?

500

An enzyme catalyzes biochemical reactions in a cell by decreasing what thermodynamic property of a reaction?

What is the activation energy?