1. Edible insects have been a part of traditional human diets in many countries. For example,
crickets are insects commonly eaten in Asia and Africa. Many studies have looked at the
prospects of raising insects on a commercial scale for direct human consumption as food
or indirectly by feeding insects to farm animals.
One factor to consider is which organisms are most efficient at converting the feed they eat
into animal protein that can be consumed. A study compared the percentage of mass that
was edible in two common farm animals and in crickets.

 (a) (i) Identify which organism has the highest percentage of edible mass. [1]
(ii) Calculate how much more feed is required by cattle than chickens to produce 1 kg of live
mass. [1]
(iii) Identify which organism requires the least feed to produce 1 kg of edible mass. [1]
The yellow mealworm (Tenebrio molitor) is native to temperate regions of the world and has
been studied as a possible means of producing food in countries with that type of climate.
The amino acid content of yellow mealworms and cattle was analysed. The table shows the
results for seven amino acids that are required in the human diet

b) (i) Distinguish between the amino acid contents of yellow mealworms and cattle. [1]
(ii) Predict, with a reason, whether the amino acid composition of yellow mealworms or cattle is
more suitable for a human diet. [1]
The environmental impact of producing protein from mealworms was compared with the
impact of producing traditional protein sources. The graphs show the greenhouse gas
production (global warming potential) and land use due to the production of 1 kg of protein
from mealworms, chickens and cattle. 
 (c) Outline the differences between the environmental impact of using mealworms and
traditional farm livestock for protein production. [2]
(d) Birds and mammals maintain constant body temperature despite considerable losses of
body heat to the environment. In insects such as mealworms, body temperature is variable and
is often the same as the temperature of the environment or only slightly above it. Analyse the
data in the bar charts, using this information. [2]
(e) Using all the relevant data in this question, discuss the use of insects as a major food
source for humans. [3]