Humans get amino acids from protiens in the food we eat. As we digest the food, the enzymes in our stomach and small intestines break down proteins into small amino acids. So technically, we do not make amino acids, we get amino acids from eating food high in protiens.
A)amino acid is the correct answer
Carbon dioxide is a colorless and non-flammable gas at normal temperature and pressure. Although much less abundant than nitrogen and oxygen in Earth's atmosphere, carbon dioxide is an important constituent of our planet's air. A molecule of carbon dioxide (CO2) is made up of one carbon atom and two oxygen atoms. Carbon dioxide is an acidic colorless gas with a density about 53% higher than that of dry air. Carbon dioxide molecules consist of a carbon atom covalently double bonded to two oxygen atoms. It occurs naturally in Earth's atmosphere as a trace gas.
<span>The tracheae possibly have evolved directly from the book lungs</span>
