Question

Triacylglycerols, with their hydrocarbon-like fatty acids, have the highest energy content of the major nutrients. Answer the following questions about energy reserves in adipose tissue. Assuming that 15% of the body mass of a 70.0 kg adult consists of triacylglycerols, calculate the total energy reserve, in units of kJ and kcal, that is available from triacylglycerols Number Number energy reserve- kcal he basal energy requirement is approximately 8,400 kJ/day (2,000 kcal/day), calculate the amount of time that this 70.0 kg person could survive if the oxidation of fatty acids stored as triacylglycerols were this person's only source of energy. Number time = days Calculate the weight loss in pounds per day under the starvation conditions in the previous part (1 lb = 0.454 kg). Number weight loss- lb/ day

Answer 1

Body mass = 70 Kg = 70000 g

15% of 70000 g = 10500 g

energy value = 9.09 kcal/g = 37.99 kJ/g

one g will provide 9.09 kcal so 10500 g will provide = 95445 kcal

its value in kJ = 95445 x 4.18 = 398960.1 kJ

b) energy required to survive for one day = 8400 kJ

398960.1 kJ i the total energy present

Therefore total no of days he will survive = 398960.1 kJ/ 8400 kJ = 47.49

=48 days

C) energy required per day = 2000 kcal

energy value = 9.09 kcal/g

weight required for one day energy = 2000 kcal /9.09 kcal g-1

= 220.02 g

= 0.220 Kg

=0.485 pound