Energy for biological processed

Question 1

Photosynthesis definition

Answer 1

The process by which energy, in the form of light (photon), is used to build up complex organic molecules eg glucose.

Question 2

Respiration definition

Answer 2

The process by which organic molecules such as glucose are broken down into smaller inorganic molecules eg CO2 and H2O.

Question 3

Equation for photosynthesis

Answer 3

6CO2 + 6H2O C6H12O6 + 6O2

Question 4

Equation for respiration

Answer 4

C6H12O6 + 6O2 –> 6CO2 + 6H2O

Question 5

Need for energy

Answer 5

• active transport (eg for sucrose loading into sieve tube cells, uptake of nitrates by root hair cells)
• anabolic reactions (eg building of polymers like proteins, polysaccharides, nucleic acids)
• movement (eg by cilia, flagella, or contractile filaments in muscle cells)

Question 6

Importance of C-H bond

Answer 6

Bond energy = either exothermic or endothermic
Large molecules like glucose require less energy to be broken, while small inorganic molecules like CO2 and H2O require a lot of energy in order to be broken.

Question 7

Chemiosmosis definition

Answer 7

The process by which protons diffuse from a region of high concentration to a region of low concentration through a partially permeable membrane. The movement of protons as they flow releases energy which can then be used to attach a Pi to ADP.