6. Cell Metabolism

Question 1

Biosynthesis

Answer 1

the generation of natural products through enzymatic reactions (cellular metabolism)

Question 2

Catalyst

Answer 2

a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

Question 3

Catalysis

Answer 3

the process of adding a catalyst to facilitate a reaction

Question 4

Diffusion

Answer 4

process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration

Question 5

Enzyme

Answer 5

proteins that help speed up metabolism, or the chemical reactions in our bodies

Question 6

Hydrolysis

Answer 6

a common form of a chemical reaction where water is mostly used to break down the chemical bonds that exists between a particular substance

Question 7

Substrate

Answer 7

an underlying substance or layer

Question 8

Energy

Answer 8

capacity to cause change, especially to do work

Question 9

Energy types

Answer 9

• Kinetic energy
• Thermal energy
• Chemical energy
• Potential energy

Question 10

Kinetic energy

Answer 10

energy associated with the
relative motion of objects

Question 11

Thermal energy

Answer 11

kinetic energy due to the
random motion of atoms and molecules (= heat)

Question 12

Chemical energy

Answer 12

energy available in molecules for
release in a chemical reaction (= potential energy

Question 13

Potential energy

Answer 13

energy that matter possesses as a
result of its location or spatial arrangemen

Question 14

Photosynthesis

Answer 14

process that converts the electromagnetic energy in sunlight into chemical-bond energy in organic molecules

Question 15

Cellular Respiration

Answer 15

a process that extracts energy from organic
molecules (food) by gradual oxidation

Question 16

Gibb’s Free Energy (G)

Answer 16

amount of energy available in a molecule to do work in a system when the temperature and pressure are uniform
- measured in in kcal/mole

Question 17

Delta G

Answer 17

free energy (C + D) - free energy (A +B)

Question 18

Exergonic

Answer 18

A. reaction with negative change in free energy (ΔG<0)

Question 19

Endergonic

Answer 19

A reaction with positive change in free energy (ΔG>0)

Question 20

Spontaneous reactions

Answer 20

• exorgenic: release energy to its
  surroundings
• energetically favorable reactions
• has a lower free energy level (more stable)
• can release the free energy (potential energy) contained in bonds

Question 21

Non-spontaneous reactions

Answer 21

• endergonic: they absorb energy from surroundings
• energetically unfavorable reactions
• has a higher free energy level than the substrate
• can store energy in molecules

Question 22

Activated Carriers

Answer 22

• store energy either as a readily transferable chemical group or as readily transferable (“high
  energy”) electrons
• ATP, NADH and NADPH (most important)

Question 23

ATP

Answer 23

• adenosine triphosphateà 1 adenosine (nitrogenous base) + 1 ribose (sugar) + 3 phosphate groups
• synthesized in an energetically unfavorable phosphorylation reaction, in
  which a phosphate group is added to ADP (adenosine 5ʹ-diphosphate)