1.Classify the following as relating to an active site, the lock-and-key model, or the induced-fit model.
an active site that has a rigid shape
an active site that adapts to the shape of a substance
the portion of an enzyme where catalytic activity occurs
2. Identify the nitrogen base and sugar in each of the following nucleotides.
dCMP
dAMP
dGMP
dTMP
In: Chemistry
2. Based on the results of the glucose test strips, under what reaction conditions did hydrolysis of sucrose occur?
3. Based the results of the glucose test strips, under what reaction conditions hydrolysis of lactose occur?
4. What do the results of the glucose test strips suggest about the enzyme specificity of invertase and lactase?
In: Chemistry
Which enzyme–substrate pair is CORRECT?
Group of answer choices
- methylmalonyl CoA mutase – 3-hydroxy-3-methyl-glutaryl CoA
- acyl CoA synthetase – acetyl CoA
- thiolase – 3-ketoacyl CoA
- hydroxymethylglutaryl CoA synthase – L-methylmalonyl CoA
- cis-Δ3-enoyl CoA isomerase – trans-Δ3-enoyl CoA
In: Biology
1. How does malonate affect the initial velocity of succinate dehydrogenase?
2. Explain why initial velocity varies directly with enzyme concentration, and how this related to the Michaelis Menten equation
3. How does malonate affect the initial velocity of an reaction?
4. What feature(s) of malonate makes it a competitive inhibitor of SDH?
In: Biology
Which of the following occurs in photoreceptors when they are exposed to the appropriate wavelength of light?
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Opsin and all-trans retinal combine to form rhodopsin. |
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PDE enzyme is activated, which increases cGMP levels. |
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Light-gated Na+ channels open, which depolarizes the cell. |
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cGMP levels decrease, which closes Na+ channels and hyperpolarizes the cell. |
In: Anatomy and Physiology
Explain the difference between nonspecific binding and specific binding using an indirect ELISA as an example. For this assay, assume that you are determining the titer of antibody against BSA.
You bind BSA to wells of a microtiter plate, add a dilution series of the antibody in question across the wells of the plate, then detect that antibody with an enzyme-conjugated antibody/chromogenic substrate pair.
In: Biology
Many pesticides work by inhibiting the action of acetylcholinesterase, the enzyme that normally breaks down acetylcholine within the neuromuscular junction. What effect would inhibition of acetylcholinesterase have on muscle tissue and why? What symptoms might you expect in cases of pesticide toxicity? What do you think is the most likely cause of death in these poisonings?
In: Anatomy and Physiology
In: Anatomy and Physiology
Match the numbers below with the correct answer on the drop down menu. On answer can be used more than once or not at all.
1. Stimulates liver for overall growth.
2. Inactive enzyme released by the liver for RAAS.
3.Zona of suprarenal glands where glucocorticoids are
secreted.
4. Main hormones secreted by the zona fasciculata of suprarenal
glands.
5. Released from suprarenal cortex and key player in RAAS.
6.Stimulates production of testosterone in males and post ovulation
phase in ovaries.
7.Stimulates production of triiodothyronine and thyroxine.
8.Stimulates release of aldosterone in RAAS.
9. Directly innervated for fast release of stress hormones.
10. Increases/opens up aquaporins in kidneys .
11.Converts angiotensin I to angiotensin II.
Oxytocin
angiotensin I
antidiuretic hormone
thyroid-stimulating hormone
angiotensin II
zona fasciculata
follicle-stimulating hormone
angiotensinogen
glucocorticoids
angiotensin-converting enzyme
suprarenal medulla
growth hormone
aldosterone
In: Anatomy and Physiology
In humans, the concentration of glucose in the blood is maintained at roughly 5 mM. Hexokinase (HK II) in muscle is a Michaelis-Menten enzyme and its KM for glucose is about 0.1 mM. The blood glucose and intracellular glucose concentrations rapidly equilibrate so that the cellular glucose concentration can be considered to be essentially the same as the blood glucose concentration. Also, prolonged high concentrations of glucose in the blood can be toxic.
a) What do the KM and the actual glucose concentration suggest about the activity of HK II under normal conditions? (In other words, how fast is the enzyme going compared to its Vmax?)
b) After a high carbohydrate meal, the blood glucose concentration can rise to concentrations much greater than 5 mM. What would be the effect of this concentration change on HK II activity in muscle tissue?
c) Given the information and your answer in part b, what would be the net effect on the person’s blood glucose concentration after a high carbohydrate meal?
In: Biology