W2-L2: Energy Metabolism

Question 1

What is Metabolism?

Answer 1

the series of chemical reactions in a living organism that create and break down energy necessary for life

Question 2

What is Metabolic rate?

Answer 2

rate at which your body expends energy or burns calories

Question 3

What are the Two broad classes of biochemical reactions that make up metabolism?

Answer 3

anabolism and catabolism

Question 4

What is Anabolism?

Answer 4

• Set of metabolic reactions that require energy to synthesize new molecules from simpler precursors
• Food intake sparks anabolism through biosynthetic pathways
• ANABOLISM - “GROWTH”

Question 5

What is Catabolism?

Answer 5

• Set of destructive metabolic reactions that transforms fuels into cellular (chemical) energy

Question 6

What are 2 Catabolic Examples involving Glucose in Metabolism?

Answer 6

• Glycogenolysis - the breakdown of glycogen to glucose
• Glycolysis - the breakdown of glucose / glycogen to pyruvate

Key word: lysis

Question 7

What three stages are involved in extracting Energy from food?

Answer 7

1. Digestion, absorption, and transportation of energy-yielding nutrients
2. Production of metabolites (end product of metabolic reactions)
3. Body’s cells can use energy-producing metabolites to completely breakdown metabolic intermediates to a form of energy that the body can use – Adenosine Triphosphate (ATP)

Question 8

What is the chemical energy derived from food used for in the body? (7)

Answer 8

1. Breathing
2. Blood circulation
3. Body temperature maintenance
4. Oxygen delivery to tissues
5. Waste removal
6. Synthesis of new tissue
7. Repairing damaged or worn-out tissues

Question 9

What is Adenosine Triphosphate?
(ATP)

Answer 9

• “Molecular unit of currency” - the primary energy molecule powering cellular functions
• Three phosphate groups attach to the organic molecule adenosine via a high energy phosphate bond

Question 10

What is the fundamental goal of energy-producing pathways in metabolism?

Answer 10

To produce ATP

Question 11

How does ATP provide energy?

Answer 11

Phosphate bonds break – energy (and Pi) are released

Pi = Inorganic Phospahte

Question 12

Where does Metabolism take place?

Answer 12

Cytosol: Glycolosis, Fatty Acid Synthesis, Glycogenesis

Mitochondrion: generates most of the Chemical Energy needed
- Krebs Cycle in Mitochondial Matrix
- ETC in Mitochondrial Membrane