<span>L-amino acids and D-sugars are part of every protein.
All proteins are made up of them.
The fact that all biological systems use L-amino acids and D-sugars is linked with the idea that certain groups of organisms come from a common ancestor because. The reason is that if the common ancestors used L-amino acids and D-sugars, than its offsprings use them as well.
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Answer:
Stratified squamous epithelium
Explanation:
Most animals, including humans, have stratified squamous epithelium in their esophagus. It may include keratin, which gives an extra layer of protection, allowing them to eat bigger and less chewed food. It should be noted that the esophagus has a mucous membrane and because of the muscular layers, called muscularis mucosae, the food can pass rapidly through it preventing damages in its layers due to coarser or abrasive food.
Answer: c. grass (producer)
The dissolved oxygen content in water
