Answer:
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Lipids are hydrophobic macromolecules
The mutation is a substitution
physical and chemical barriers that form the first line of innate defense include the acidity of the stomach, tear fluid from the eye, an un-punctured skin and mucus and cilia of the respiratory tract.
Food is digested by the stomach, a J-shaped organ. It generates acids and enzymes. Food is broken down by this concoction of digestive juices and enzymes so that it may move on to your small intestine. The digestive system includes your stomach. Humans and many other animals, including numerous invertebrates, have a muscular, hollow organ called the stomach in their gastrointestinal tracts. The stomach is a crucial organ in the digestive system and has a dilated configuration.
In animals, the respiratory system is divided into the respiratory tract, which is engaged in the respiration process. The respiratory epithelium and respiratory mucosa line the respiratory tract. There are upper and lower airways in the respiratory tract.
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