BLG Quiz Chapter 23 & 24

Question 1

Define Anabolism

Answer 1

The synthesis of large molecules from small ones (i.e., synthesis of proteins from amino acids)

Question 2

Define Catabolism

Answer 2

The hydrolysis of complex structures to simples ones (i.e., breakdown of proteins into amino acids)

Question 3

Define Cellular Respiration

Answer 3

the catabolic breakdown of food fuels whereby energy from food is captured to form ATP in cells

Question 4

Define Phosphorylation

Answer 4

Enzymes that shift high-energy phosphate groups of ATP to other molecules; phosphorylated molecules become activated to perform cellular functions

Question 5

Describe the 3 stages of metabolism

Answer 5

Stage 1: GI Tract: nutrients (i.e., carbohydrates, proteins, fats) are digested into absorbable units (i.e., glucose, amino acids, glycerol/fatty acids). They are absorbed into the blood and transported to tissue cells.
Stage 2: Tissue Cells: Anabolism or Catabolism: In anabolism, nutrients are built into macromolecules; in catabolism, nutrients are partially broken down. Glycolysis is the major catabolic pathway and ends with pyruvate.
Stage 3: Mitochondria: Oxidative breakdown of stage 2 products: CO2 is released, the Hydrogen atoms removed are ultimately delivered to molecular oxygen - forming water, Some of the energy released is used to form ATP, The citric acid cycle and oxidative phosphorylation are the major pathways

Question 6

Define Oxidative reactions

Answer 6

Reactions involving the gain of oxygen or loss of hydrogen atoms (and their electrons)

Question 7

Define Oxidation-reduction (redox) reactions

Answer 7

Reactions whereby oxidized substances lose electrons and energy and reduced substances gain electrons and energy. Redox reactions are catalyzed by enzymes that usually require a B vitamin coenzyme (NAD+ or FAD)

Question 8

What are the two mechanisms used to make ATP from captured energy that is liberated during cellular respiration?

Answer 8

1. Substrate-level phosphorylation: high energy phosphate groups are directly transferred from phosphorylated substrates to ADP
2. Oxidative phosphorylation: is a chemiosmotic process that couples the movement of substances across membranes to chemical reactions