Fimbrin Arp 2/3 Alpha-actinin 28.) What part of the cell should show the most evidence of loosely crosslinked actin meshworks? filipodia lamellipodia the cytoplasm inside contractile bundles
29.) What actin-based structure is shared in common between filipodia and microvilli? Contractile bundle Dense meshwork Tight parallel bundle 30.) What distinguishes anchoring junctions from other junction types? Choose the best answer. This junction type directly prevents solute movement between cells. This junction type enables solute transfer from the cytoplasm of one cell to another. All anchoring junctions are associated with actin or intermediate filaments. These junctions anchor the nucleus to the cell periphery via microtubule attachments. Misc wrap-up questions 32.) Which of the choices below describes a beta barrel, integral membrane protein? Porin in the outer mitochondrial membrane Bax/Bak pore in the outer mitochondrial membrane Nuclear pore ER translocon All of the answers listed here refer to beta barrel proteins. 33.) You see a research paper announcing that “autophagy enables the translation of the DNA damage repair protein BRCA2.” How would you interpret this news? That’s surprising, because autophagy is usually discussed in terms of eliminating malfunctioning organelles in the cytoplasm. Not surprising, because the nucleus is the primary site for autophagy function anyway.
34.) Synthetic insulin, administered for management of diabetes, would be referred to as what sort of ligand? Agonist Antagonist Protagonist Prions 35.) Consider a cell surface protein like the LDL receptor. How do transmembrane proteins like this get placed in the plasma membrane? Chaperonins bind the hydrophobic parts of the receptor protein as it’s translated, enabling direct import later into the plasma membrane. This protein is imported across the ER bilayer during its translation. Then this protein is secreted to the plasma membrane through membrane trafficking from the ER to the Golgi, and then from the Golgi to the cell surface. 36.) Which statement best describes how microtubule motor proteins contribute to mitosis? Cytoplasmic Dynein carries the chromosomes toward the spindle poles. Kinesin-1 is critical to push the spindle poles apart. MCAK drives Anaphase by destabilizing the structure of microtubules.These motors form a thick filament that drives constriction of the cytokinesis ring. 37.) A friend got a paper cut from his study notes. Platelets that aggregate at the wound site release growth factors that activate RTKs on nearby cells. What effect do you expect this to have? It will activate Rtk-Ras signaling, driving cells to grow and proliferate at the wound site. It will cause the skin cells to undergo the epithelial-mesenchymal transition. This signaling cue will trigger local neurons to report pain at the wound site. It will cause any microbially contaminated cells to undergo apoptosis.