Intro To Metabolism

Question 1

Metabolism and metabolic pathways

Answer 1

Metabolism: totality of an organisms chemical processes, concerned with management of energy and resources of the cell

Metabolic pathways: begins with a specific molecule which is the altered in a series of steps, each regulated by a specific enzyme, resulting in a product (often reversible steps) regulated by supply and demand

Question 2

Anabolism

Answer 2

Total series of chemical reactions involved in synthesis of organic compounds, energy is consumed within the cell

Ex: synthesis of protein

Question 3

Catabolism

Answer 3

Chemical reactions that break down larger molecules
energy released, some used for anabolism

Question 4

Energy coupling

Answer 4

Transfer of energy from catabolism to anabolism

Question 5

potential energy

Answer 5

Gradient represents potential energy

Molecules posses energy because of electrons in the bonds between their atoms

Catabolic pathways release energy by breaking down complex molecules (ex glucose) it’s about 40% efficient, rest is released as heat which helps regulating body heat

Question 6

Chemical energy

Answer 6

Chemical energy is potential energy available to be released in a chemical reaction

stored in molecules because of the structural arrangement of the atoms and molecules

Also called bond energy

only kind of energy that can do work in a cell (joules mole-1 )

Exergonic resctions: energy released, spontaneously

Endergonic: contrary, ex photosynthesis

Question 7

Spontaneous process

Answer 7

Occurs without outside help, increases stability

Free energy decreases

Must give up energy or order or often both

Greater decrease of free energy treated aenount of work can be done

Question 8

Glucos into cells

Answer 8

Facilitated transport added by insulin caused vesicles

Question 9

Cell does 3 main type of work

Answer 9

Mechanical work: cotraction of muscles cells

Transport work: active transport

Chemical work: pushing endergonic reactions ex synthesis of polymers

Source of energy is ATP

Question 10

atp coupling by phosphorylation

Answer 10

using enzyme, Atp hydrolized, releases energy, (exergonic reaction)

then phosphate is moved from atp to some other molecule, (endergonic reaction) produces adp,

phosphorylation intermediate is more reactive/less stable than original molecule ex sodium postassions pumps, which leads it to be pushed into the endrogonic reaction more easily

Hydrolysis of Atp drives mechanical work by phosphorylation motor protein (changes in conformation at each step of atp phosphorylation)

Question 11

Energy coupling

Answer 11

Substrate is converted into something with higher chemical potential by using another (coupling it) reaction that is exergonic so that it runs spontaneously and uses the energy from the exergonic reaction to produce the endorgonic reaction

Question 12

Recycling atp

Answer 12

Working muscles cell recycles it’s atp

Question 13

Free energy (G)

Answer 13

amount of energy available to do work under the conditions of a biochemical reaction

Question 14

enthalpy(H)

Answer 14

The total potential energy of a system

Question 15

energy types

Answer 15

energy: ability to bring about change or do work
potential energy: stored energy, not yet been used
kinetic energy: energy in use

Question 16

Free energy changes (ΔG)

Answer 16

depends mainly on the difference in bond energies (H) between reactants and products and on the [reactants] and [products]

Question 17

disequilibrium of metabolism

Answer 17

living cell cannot be at equilibrium
constant flow of materials in and out of cell keeps it from reaching equilibirum