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The figure below shows how normal signaling works with a Ras protein acting downstream of a receptor tyrosine kinase.  For a cell line with an inactive Ras protein, which of the following conditions will turn on this signaling pathway? Indicate Yes or No for each condition. addition of a drug that activates the receptor tyrosine kinase [1] addition of a drug that increases the interaction between protein Y and Ras  [2] addition of a drug that blocks protein Y from interacting with its target [3] addition of a drug that directly activates protein Y [4]

Select the size closest to the diameter of intermediate filament, actin filament and microtubules from the options provided intermediate filament [1] actin filament [2] microtubules [3]

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below. Not all words or phrases will be used; use each word or phrase only once. Microtubules are formed from tubulin [1]. Tubulin subunits are stacked together into protofilaments; thirteen parallel protofilaments form the [2] structure of a microtubule. Therefore the structures of the two ends of the microtubule are [3]. [4] ring complexes are important for microtubule nucleation and are concentrated in the [5]. A microtubule that is quickly growing will have a string of [6] tubulins that helps prevent the loss of subunits from its growing end. The motor protein [7] generates the bending motion in cilia.

Indicate whether the following statements are true or false.  The membrane of a secretory vesicle will fuse with the plasma membrane when it discharges its contents to the cell’s exterior. [1] Vesicles for regulated exocytosis will not bud off the trans Golgi network until the appropriate signal has been received from the cell. [2] Often, the fusion of the secretory vesicles with the plasma membrane is stimulated by the decrease of cytoplasmic [Ca2+] [3] The secretion of insulin is an example of regulated secretion. [4]

Indicate whether the following statements are true or false. An antibiotic that inhibits protein synthesis of a bacterium will likely inhibit protein synthesis in mitochondria. [1] The mitochondria are thought to have evolved by invagination and pinching off from the plasma membrane of an ancient eukaryotic cell. [2] Most mitochondrial proteins are translated in the cytosol. [3] Reovirus enters into the target cell by engaging with the surface receptor on the target cell, which in turns triggers the assembly of clathrin coat on the cytoplasmic side. [4] Reovirus is activated when an outer shell viral protein is attacked by an intestinal protease.[5] Per pumping cycle, the sodium-potassium antiporter transports one sodium ion into the cell and one potassium ion out of the cell. [6] The electrical potential of a charged molecule is not zero if the membrane potential is not zero.  [7]

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below.  Not all words or phrases will be used; each word or phrase should be used only once. There are several ways that membrane proteins can associate with the cell membrane.  Membrane proteins that extend through the lipid bilayer are called [1] proteins and have [2] regions that are exposed to the interior of the bilayer. Some other proteins are [3] attached to lipid molecules that are inserted in the membrane.  [4] membrane proteins are associated with the membrane through noncovalent interactions with other membrane-bound proteins. In animals, proteins constitute ~ [5] of the total mass of the plasma membrane. Transmembrane proteins that are destined for the plasma membrane are first inserted into the membrane of the [6]. 

After isolating the rough endoplasmic reticulum from the rest of the cytoplasm, you purify the RNAs attached to it.  Indicate whether you expect these RNAs to encode the following types of proteins (Indicate Yes or No for each type of the proteins). proteins to be inserted into the plasma membrane [1] proteins to be delivered to the Golgi apparatus [2] proteins to be imported into the nucleus [3] proteins to be secreted to the extracellular space [4]

In the textbox, compose your rough draft for Paragraph 2.  You should consult your outline (a printed copy) as you work on the paragraph. 

Write the equation of the line that passes through the point P(4, 3) and is perpendicular to the line y = – 5x + 2.​

Find (fg)(x).​\(\style{font-family:Times New Roman}{f(x)=x^2,\;g(x)=\text{7}x-\text{7}}\)​