Chapter 8: An Introduction to Metabolism

Question 1

metabolism

Answer 1

totality of CR, consisting of catabolic and anabolic pathways, and manage the material and energy resources of the organism

Question 2

metabolic pathway

Answer 2

series of CR that build (anabolic) a complex molecule or break down (catabolic) a complex molecule to simpler molecules

Question 3

catabolic pathway

Answer 3

metabolic pathway that releases energy by breaking down complex molecule into simpler ones

Question 4

anabolic pathway

Answer 4

metabolic pathway that consumes energy to make complex molecules

Question 5

bioenergetics

Answer 5

the overall flow and transformation of energy through an organism, the study of how energy flows through an organism

Question 6

energy

Answer 6

capacity to cause change, especially to do work (to move matter against an opposing force)

Question 7

kinetic energy

Answer 7

energy from movement of ions

Question 8

thermal energy

Answer 8

random movement resulting in energy

Question 9

potential energy

Answer 9

potential for energy, stored energy

Question 10

chemical energy

Answer 10

energy from chem reactions

Question 11

first law of thermodynamics

Answer 11

energy cannot be created or destroyed, only transferred or transformed (conservation of energy)

Question 12

second law of thermodynamics

Answer 12

every transfer or transformation of energy increases the entropy of the universe. usable forms of energy are at least partly converted to heat.

Question 13

exergonic reaction

Answer 13

spontaneous chemical reaction that there is a net release of free energy

Question 14

endergonic reaction

Answer 14

nonspontaneous chemical reaction in which free energy is absorbed from the surroundings

Question 15

adenosine triphosphate

Answer 15

atp, adenine-containing nucleoside triphosphate that releases free energy when its phophate bonds are hydrolyzed. Drives endergonic reactions.

Question 16

catalyst

Answer 16

chemical agent selectively increases the rate of a reaction w/o being consumed by the reaction

Question 17

enzyme

Answer 17

protein, speeds chemical reactions, can be used over and over and over again

Question 18

substrate

Answer 18

substance that combines with the enzyme (at the active site) to make the chem reaction happen

ex. lactose (substrate) and lactase (enzyme)

Question 19

enzyme-substrate complex

Answer 19

temporary complex formed when an enzyme binds to its substrate molecule

Question 20

cofactor

Answer 20

nonprotein molecule or ion that binds to the enzyme’s active site for proper functioning of an enzyme (sometimes permanently bound, or losely bound during catalysis)

Question 21

coenzyme

Answer 21

an organic molecule serving as a cofactor. Most vitamins act as co-enzymes in metabolic reactions.

Question 22

competitive inhibitors

Answer 22

reduces the activity of an enzyme by entering the active site in place of the substrate, whose structure it mimics

Question 23

noncompetitive inhibitors

Answer 23

substance that reduces the activity of an enzymes by binding to a remote location from the active site, changing the enzymes shape so the active site no longer effectively catalyzes the conversion of the substrate to product

Question 24

feedback inhibition

Answer 24

method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway

Question 25

What are the three types of work that a cell does? Explain and/or provide examples of each.

Answer 25

Chemical- the pushing of endergonic reactions that would not occur spontaneously (like synthesis of monomers to polymers)
Transport- pumping of substances across membranes against the direction of spontaneous movement (active transport…sodium-potassium pump)
Mechanical- beating of cilia, contraction of muscle cells, movement of chromosomes during cellular reproductions

Question 26

What is adenosine triphosphate? Why is it important? Describe its chemical structure.

Answer 26

***revisit this in the video lecture
ATP- a sugar (ribose) with the nitrogenous base (adenine) and a chain of 3 phosphates (triphosphate group)
Nucleoside responsible for producing free energy in high amounts during it’s breakdown (hydrolysis)
it is useful to the cell bc it produces more energy than any other molecule. It produces the energy for all the work done in the cell.