Final answer:
The synonym for rancid is (d) 'rancidity,' which refers to the condition of fats that have spoiled due to processes like hydrolysis and oxidation. Antioxidants like vitamin E and vitamin C can prevent rancidity by protecting the molecular structure of cell membranes.
Step-by-step explanation:
The synonym for rancid is d. Rancidity. Rancidity is a term that describes the unpleasant taste and odor of fats that have undergone degradation, primarily through the processes of hydrolysis and oxidation. This degradation can be influenced by enzymes like lipase, atmospheric moisture, and temperature.
To prevent rancidity, substances such as antioxidants, which include vitamin E and vitamin C, can be employed. These antioxidants function by interrupting the chain reactions that lead to further degradation of the fats. Understanding the role of antioxidants can contribute to preserving the molecular structure of a cell membrane, which consists of a lipid bilayer with a mix of polar lipids and proteins.