Cellular energetics

Question 1

Metabolism

Answer 1

To be able to grow divide and carry out day to day activity and the cells require a constant supply of ATP and the cells obtain energy from food molecules

Question 2

Autotrophs

Answer 2

plants and algae produce own nutrients

Question 3

Catabolism

Answer 3

Breakdown of compelx molecules

Question 4

Anabolism

Answer 4

Synthesis of complex molecules

Question 5

Respiration

Answer 5

• Break down sugars and other metabolites to CO2 and water
• Convert energy released from food into the build of ATP the terminal phosphoanhydride bond
• Requires aerobic process requires oxygen except glycolysis
• NAD+ and FADH are coenzymes

Question 6

ATP

Answer 6

• The phosphoanhydride bonds between the three phosphate bonds
• Phosphodiester bond between the phosphate and ribose (deoxy)
• Adenine bonded to the ribose
• Hydrolysis of high energy phosphate bonds between the gamma & beta energy release
• ATP -> ADP + phosphate + energy

Question 7

Glycolysis

Answer 7

• Split sugar break down glucose to 2 pyruvate
• 2 ATP and +2 NADH
• Glycolysis occurs in cytoplasm
• No requirement for oxygen
• Energy investment 2 ATP for phosphorylation
• Making the glucose polar by hydrolysis of ATP
• Energy generation phase 2 NADH and 4 ATP
  Net gain of 2 Pyruvate & 2 ATP & NADH

Question 8

Fermentation

Answer 8

• Occur in cytoplasm no oxygen
• No energy produce restore NAD+ use in glycolysis
• Pyruvate is reduced to lactic acid in muscle cells
• NADH + H+ -> NAD+
• Ethanol reduced to co2 and ethanol production of NAD+ for glycolysis

Question 9

Pyruvate oxidation

Answer 9

• In presence of O2 and pyruvate forms acetate then binds to acetyl coenzyme A

Question 10

Breakdown of fat

Answer 10

• Fat store in triacylglycerol 3 fatty acid linked to glycerol
• Lipase hydrolase ester bond release

Question 11

Citric acid cycle

Answer 11

• Require O2 in mitochondrial matrix
• Acetyl coenzyme A added to oxaloacetate (4c) forms citric acid (6c)
• Acetyl group is fully oxidised to co2 and water
• Oxalacetate is regenerated
• Reduction of 2 electron carrier
• Turn 2 times for 1 glucose

Question 12

Oxidative phosphorylation

Answer 12

• NADH and FADH2 transfer high energy electrons to ETC composed of 4 protein complex
• Electrons through the proteins imbedded
  Chemiosmosis:
• Proton gradient drive synthesis of ATP
• Pump protons from intermembrane space to matrix
  ADP pump into matrix and ATP pumped out by antiport

Question 13

Overall energy per glucose

Answer 13

• Glycolysis - 2 ATP
• Pyruvate oxidation - 2 ATP
  Oxidative phosphorylation - 26 or 28 ATP