In terms of animal diets, which other macronutrient supports growth and repair of tissues?

The correct answer is proteins because they play a crucial role in the growth and repair of tissues in animals. Proteins are made up of amino acids, which are the building blocks necessary for the synthesis of new cells and tissues. This makes them essential for development during growth periods, as well as for recovery and healing after injuries or illnesses.

In addition to their structural roles in tissues like muscles and skin, proteins are involved in various important biological functions, such as enzyme activity and immune function, which further highlight their significance in maintaining an organism's health and growth.

Vitamins, while essential for various biochemical processes and overall health, do not directly contribute to tissue growth and repair. Fats are primarily a source of energy and serve important roles in cell structure and hormone production but are not directly responsible for tissue formation. Minerals are vital for numerous physiological functions and in supporting enzyme activities but also do not play a direct role in tissue growth and repair like proteins do.