BIOL 1201 Lecture : 9 19 14 Notes

7 views2 pages

azuremammoth471

15 Mar 2019

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Inhibitor binds to the active site and blocks access to the active site. Inhibitor binds to a site other than the active site and alters the shape of the active site. Allosteric inhibition/regulation: enzyme alters between active and inactive forms. Inhibitor binds to a site other than the active site and stabilizes one shape of the enzyme (inactive shape) Cells: the minimum organization of living matter. Fluid-mosaic model: phospholipid bilayer with a mosaic of associated proteins. Cell coat: composition: glycolipids and clycoproteins, function: cell recognition. Why do cells have membranes: structure the cell has to be held together and contained, function what holds the cell together and keeps it contained is more important. Functional properties: maintain concentration of molecules and ions, create free energy gradients, orient molecules into functional complexes. Membrane permeability: size and shape of molecules, solubility in lipids, net electric change, other chemical properties, water always freely permeable to the membrane.

Related Questions

Explain how the following mechanisms regulate enzyme activity.

Part A

Covalent modification

a)The product of a series of reactions acts as an inhibitor for an earlier reaction.

b)Hormones control the synthesis of enzymes.

c)A regulator binds to the enzyme at a site other than the active site. This binding changes the shape of the enzyme and alters the catalytic ability of the enzyme.

d)An inhibitor binds reversibly to the enzymesubstrate complex, blocking the binding of the second substrate to the active site.

e)The activity of an enzyme is influenced by the addition or removal of a group that is covalently bonded to the enzyme.

f)An inhibitor forms covalent bonds to the active site, permanently blocking it.

Part B

Genetic control

a)The product of a series of reactions acts as an inhibitor for an earlier reaction.

b)Hormones control the synthesis of enzymes.

c)A regulator binds to the enzyme at a site other than the active site. This binding changes the shape of the enzyme and alters the catalytic ability of the enzyme.

d)An inhibitor binds reversibly to the enzymesubstrate complex, blocking the binding of the second substrate to the active site.

e)The activity of an enzyme is influenced by the addition or removal of a group that is covalently bonded to the enzyme.

f)An inhibitor forms covalent bonds to the active site, permanently blocking it

Part C

Allosteric regulation

a)The product of a series of reactions acts as an inhibitor for an earlier reaction.

b)Hormones control the synthesis of enzymes.

c)A regulator binds to the enzyme at a site other than the active site. This binding changes the shape of the enzyme and alters the catalytic ability of the enzyme.

d)An inhibitor binds reversibly to the enzymesubstrate complex, blocking the binding of the second substrate to the active site.

e)The activity of an enzyme is influenced by the addition or removal of a group that is covalently bonded to the enzyme.

f)An inhibitor forms covalent bonds to the active site, permanently blocking it.

Part D

Feedback inhibition

a)The product of a series of reactions acts as an inhibitor for an earlier reaction.

b)Hormones control the synthesis of enzymes.

c)A regulator binds to the enzyme at a site other than the active site. This binding changes the shape of the enzyme and alters the catalytic ability of the enzyme.

d)An inhibitor binds reversibly to the enzymesubstrate complex, blocking the binding of the second substrate to the active site.

e)The activity of an enzyme is influenced by the addition or removal of a group that is covalently bonded to the enzyme.

f)An inhibitor forms covalent bonds to the active site, permanently blocking it

3) The hydrolysis of sucrose to glucose and fructose is exergonic. However, if you dissolve sucrose in water and keep the solution overnight at room temperature, there is no detectable conversion to glucose and fructose. Why?

Select one:

a. The change in free energy of the reaction is negative.

b. The activation energy of the reaction is high.

c. The free energy of the products is higher than the free energy of the reactants.

d. This is a condensation reaction.

e. The change in free energy of the reaction is positive.

5) Competitive inhibition differs from non-competitive inhibition in that the ___1___ site is where we see competitive inhibition, while the non-competitive inhibitor __2___.

1. a. allosteric b. non-active c. active d. hydrophillic e. hydrophobic

2.
a. binds to the active site, thus blocking it
b. binds outside the active site, changing the shape of the enzyme
c. binds outside the active site, and blocks the active site

6) Phosphofructokinase is an enzyme, and as such it __1___ of the reaction. It is part of glycolysis, and is an example of an enzyme controlled by inhibition, as high levels of citrate (an intermediate further down the catabolic pathway) turns the enzyme off
(1)Select one:
a. lowers activation energy
b. lowers the ÎG
c. raises the Free Energy
(2)Select one
a. non-competitivenegative feedback
b. irreversible competitivereversible competitive.

15)The reactions in the pathways of glycolysis and the citric acid cycle harvest the high-energy electrons stored in glucose. Therefore, these pathways _______________.

Select one:

a. take place in animal cells, but not in plant cells
b. are catabolic pathways
c. are anabolic pathways
d. involve the reduction of glucose and its metabolic intermediates

21) In an exergonic chemical reaction, the products have less free energy than the reactants (-ÎG). Endergonic reactions require an input of energy (+ÎG). The addition of starting materials and the removal of end products prevent metabolism from reaching final equilibrium. Instead, the cell exists in a state of dynamic equilibrium.

Select one:
True
False

greyferret515

Cells from which domain(s) of life are separated from theirenvironment by a plasma membrane? Select all correct choices.bacteria archaea eukarya 2. The active maintenance of a constantenvironment is referred to as: stability. homeostasis. symmetry.equilibrium. balance. 3. The electrical component of anelectrochemical gradient is due to: the use of ATP as an energysource to drive primary transport. a greater concentration ofpositive charges on the side of the membrane with the highestconcentration of protons. a greater concentration of positivecharges on the side of the membrane with the lowest concentrationof protons. a higher pH on the side of the membrane with the lowestconcentration of protons. a higher pH on the side of the membranewith the highest concentration of protons. 4. Which one of thefollowing would be found in the cells of a blade of grass but notin the cells of an insect feeding on that grass? Select all correctchoices. chloroplasts cytoskeletal elements mitochondriaendoplasmic reticulum nuclei 5. With which of the following is asignal-recognition particle (SRP) capable of interacting? Selectall correct choices. a signal sequence in a protein destined forthe ER a ribosome an SRP receptor 6. Which one of the followingcellular compartments does not have a double membrane structureseparating it from the rest of the cell? Select all correctchoices. mitochondria chloroplasts lysosomes the nucleus 7. True orFalse: purified phospholipids will gather together and formmembranes only if the appropriate enzyme is present. false true 8.Which component(s) of a phospholipid would most likely be found inthe interior of a lipid bilayer? Select all correct choices.glycerol fatty acids phosphate 9. Some drugs are now beingdelivered into cells through liposomes, where the drug issurrounded by a phospholipid bilayer. How do the drugs enter intothe cell? The liposome fuses with the phospholipid bilayer of thecell. The drug destroys the liposome and is transported viadiffusion into the cell. Protein channels on the cell surfacetransport the liposomes into the cell. The liposome cuts a hole inthe cell and injects the drug into the cell. 10. Some diseases canresult from defective transport across the membrane. For example,cystic fibrosis results from a chloride ion transporter that doesnot function. Which of the following would be affected when thistransporter does not function? the electrical gradient of the cellthe chloride concentration gradient Neither the chlorideconcentration gradient nor the electrical gradient of the cell Boththe chloride concentration gradient and the electrical gradient ofthe cell

tealbuffalo995

BIOL 1201 Lecture : 9 19 14 Notes

Document Summary

Get access

Related Documents

BIOL 1201 Chapter : Biology 2

BIOL 1201 Chapter : BIO1201E2

BIOL 1201 : BIOL1201 Exam 2 Notes

Related Questions