Metabolic Processes

Question 1

Metabolism

Answer 1

Regulates how energy is used in the body
Primarily determined by the liver

3 factors (how energy is used)
Basal metabolic rate (BMR)
Physical activity
Thermal effect of food (TEF)

In order to regulate energy needs - chemical reactions happen to change matter or energy in the cell → metabolic pathways is the sequence

Question 2

Basal metabolic rate

Answer 2

Bodily functions that sustain life → breathing, circulating blood, maintaining body temperature

Adults use 2/3 - 3/4 of calories burned → accounting for 60 - 75% of total energy requirements

Question 3

Total energy expenditure (tee)

Answer 3

Amount of energy you need in a day

Question 4

Physical activity

Answer 4

→ Execise increases metabolism (based on duration and intensity)
→ more muscle = increased metabolism, greater muscle to fat ratio
→ increase in age (also causing hormone level changes and decreased muscle to fat ratio) decreases metabolic rate
→ energy required increases with body weight
→ 15-30% of total energy requirements

Question 5

Thermic effect of food

Answer 5

Diet-induced thermogenesis
→ energy requirements increase several hours after a meal due to; digesting, absorbing, metabolizing, & strong nutrients
→ 5-10% of total energy requirements
→ TEF increases with the size of meals (small frequent meals don’t need to conserve energy therefore metabolism speeds up), meals high in carbs and proteins compared to fats
→ fasting decreases metabolism

Question 6

Energy

Answer 6

Capacity to do work
Main types;
→ kinetic, energy of motion
→ potential, stored energy
→ chemical, potential energy stored in the bonds of a compound
→ bond, amount of energy needed to form/ break a bond (both are equal)

Question 7

ATP

Answer 7

Adenosine triphosphate (is nucleic acid)
Primary source of free energy in living cells
Structure: nitrogenous base (adenine) attached to 5-carbon sugar ribose bound to a chain of 3 phosphate groups

Question 8

How is energy obtained from ATP

Answer 8

→ atpase (enzyme) catalyzeS the hydrolysis (cut-off) of the end phosphate group making it ADP
→ one pi (phosphate groups on their own) is released with a lot of energy
→ energy isn’t always freely released, pi can phosphorylaTe to other molecules (add phosphate to) - changing shape and making then more active (active transport)