Concepts from Practice Tests Flashcards
What is phenylhydrazine?
phenyl attached to two amino groups, PhN2H4.
What is a hydrozone?
R2C=NNR2
What does methyl propenoate look like?
Methyl attached to sp3 oxygen, not from carbonyl. Propyl comes from side attached to carbonyl.
Being next to an electronegative atom makes the proton shift downfield or upfield in H-NMR?
Downfield, toward bigger ppm values because they are more shielded
What are carbenes?
Carbon with only two bonds and then a pair of lone pairs
H2C:
What is kinetic control?
The product determined by kinetics is the one that forms fastest, regardless of stability. This means that on a reaction profile, the product obtained under kinetic control will have a relatively low activation energy. This lesser energy of activation simply means that less energy is required to form the transition state (getting over the “hump” of the energy profile), further facilitating a faster product formation.
What is thermodynamic control?
The major product of thermodynamic control will be the one that is most stable, not necessarily the fastest-forming product. This product has a lower Gibbs free energy, but may actually require a higher activation energy to reach the transition state. As such products formed under thermodynamic control are typically more difficult to obtain, due to the high energy of activation needed to ensure the formation of the transition state—yet the stability of such a product is significantly greater than that of a kinetic-favored product.
In recrystallization, what is the purpose of washing crystals in a Hirsch funnel with cold water?
Remove soluble impurities.
Depending on the experiment, one might want to remove the impurities from the aqueous or the solid part of the product. In our experiment, we are interested in collecting the crystals formed, and therefore want to remove the impurities found in the aqueous part of the product. Washing the crystals with cold water is designed to remove impurities that are soluble in the aqueous wash. As the crystals are washed, the soluble impurities dissolve in the wash and are consequently washed away from our desired product, traveling down the Hirsch funnel. Insoluble purities are not dissolved in the wash and remain with the crystals on the filter paper.
What is the function of aldosterone?
Aldosterone is a hormone that aids in the regulation of blood pressure—it is a mineral corticoid secreted by the adrenal gland. What causes its secretion? Aldosterone is secreted in response to low sodium concentration. The kidneys, in return, respond to aldosterone by increasing the active resorption of sodium; as a result, water is passively
reabsorbed along with the sodium ions. The increased water resorption results in increased blood volume and,
consequently, increased blood pressure.
How is blood pressure and urine output related?
Blood pressure is responsible for forcing the plasma out of the renal artery into Bowman’s capsule. The fluid that reaches Bowman’s capsule is filtered by the kidneys. The amount of fluid reaching the Bowman’s capsule directly
determines the glomerular filtration rate, and an increase in the latter will result in an increased urine output. An increase in blood pressure results in more plasma being forced into Bowman’s capsule—as a result, the glomerular filtration rate increases, as does the urine output.
How does the kidneys respond to decreased glomerular blood pressure?
The decreased blood flow to the kidneys will result in decreased fluid reaching Bowman’s capsule and decreased blood being filtered by the kidney (the kidneys will sense the decreased blood flow as decreased glomerular blood pressure). Since the kidneys sense the decreased blood flow, they will attempt to increase blood flow. As the decreased blood flow is presumed to be caused by decreased body volume, the kidneys will respond by increasing the reabsorption of sodium and water. By increasing the resorption of sodium and water, the kidneys ensure an increase in blood volume. Such renal response ultimately culminates in an elevation in blood pressure. We expect, therefore, that reducing the blood flow to the kidneys would lead to hypertension.
If blood flow increased by 50%, that means?
The new blood flow is 1.5 times the old blood flow. When they say increased by, you add that fraction/percentage to 100%, not multiple, read the answer choices carefully.
Where is cardiac muscle found?
Cardiac muscle is found solely in the heart, not in the arteries. The cardiac muscle must work harder in response to increased blood pressure but does not cause increased blood pressure.
What is the purpose of the Golgi apparatus?
The Golgi apparatus is the distribution center of the cell; it packages materials to be excreted and sends them to the cell membrane. The Golgi apparatus packages
already-made proteins and sends them to the cell membrane.
Where does filtration take place in the kidneys?
Glomerulus.
As blood enters the kidney, it first enters the glomerulus, which is a bundle of capillaries. The blood pressure forces plasma into Bowman’s capsule—the glomerulus acts as a strainer, allowing filtration of smaller molecules and fluid into the Bowman’s capsule. Molecules that are too large
to exit the glomerulus remain in the blood circulation. The glomerulus, therefore, is the point of filtration; in fact,
all of the filtration in the kidney occurs in the glomerulus.
