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The actin subunits at the plus end of a polymerizing actin filament most likely contain 

Rod photoreceptor cells are responsible for vision in dim light. The figure shows the pathway through which rod photoreceptor cell senses light. Predict whether the following mutations will result in a) night blindness (poor or no eye-sight in dim light)  b) prolonged response to a short light flash  Hint: The block of the activation pathway will result in night blindness.  The inhibition of the deactivation pathway will result in prolonged response to a short light flash. [answer1] Rhodopsin is inactive [answer2] guanylyl cyclase is inactive [answer3] Rhodopsin kinase is inactive [answer4] Regulator of G-protein signaling protein is inactive [answer5] The cGMP phosphodiesterase is inactive

The figure below shows how normal signaling works with a Ras protein acting downstream of a receptor tyrosine kinase.  You obtained a cell line, in which the Ras protein is mutated and cannot be activated. Which of the following conditions will turn on this signaling pathway in this cell line? Indicate Yes or No for each condition.   [answer1] addition of a drug that prevents protein X from interacting with Ras [answer2] addition of a drug that decreases the activity of protein Y [answer3] addition of a drug that decreases the activity of the receptor tyrosine kinase [answer4] addition of the signal molecule that activates the receptor tyrosine kinase

For each statement below, determine whether each condition will promote microtubule polymerization or depolymerization. The addition of a drug that caps the plus end of the microtubule and prevents subunit exchange at the plus end will promote microtubule [answer1]. The addition of a drug that prevents GDP-tubulin from dissociating from the polymer will promote microtubule [answer2]. The addition of a drug that inhibits GTP hydrolysis in subunits incorporated into the polymer will promote microtubule [answer3]. The addition of a drug that promotes GTP hydrolysis in the microtubule will promote microtubule [answer4].

Which of the statements below about intermediate filaments is true?

What are the key elements to successful closed-loop thinking in lean management?

Normally, when blood glucose level increases (e.g. after a meal), the islet cells in the pancreas secrete insulin. When insulin molecules bind to insulin receptors on the surface of a muscle cell, the receptors become activated, initiating a signaling pathway which eventually results in the increase in the number of passive glucose transporters on the muscle cell surface thus increases the uptake of glucose.  Which one of the following conditions will likely result in diabetes?

According to W. Edwards Deming, what is a key feature of organizational leadership?

Indicate whether the following statements are true or false.  [answer1] Reovirus enters into the target cell by first being captured as a “cargo” into a endocytic vesicle. [answer2] Reovirus is activated when an outer shell viral protein is attacked by an intestinal protease. [answer3] The nuclear envelop is thought to have evolved by invagination and pinching off from the plasma membrane of an ancient archaeon. [answer4] An antibiotic that inhibits protein synthesis of a bacterium will likely inhibit protein synthesis in mitochondria. [answer5] Most mitochondrial proteins are made within mitochondria.  [answer6] The electrical potential of a charged molecule is zero if the membrane potential is zero.

Which of the following statements regarding the nucleus is true?