Answer:
1. Outer layer of cells --- Epidermis
2. Tube connecting the mouth to the stomach --- Esophagus
3. Iron compound in red blood cells --- Hemoglobin
4. The distal half of the small bowel --- Ileum
5. The middle part of the small bowel --- Jejunum
Explanation:
1- The epidermis, in vertebrates, is the outer layer of the skin. It is the body's most important barrier to the external environment of the skin.
2- The esophagus is a part of the digestive system of both vertebrate and invertebrate living beings formed by a muscular tube of about 25 centimeters, which connects the pharynx with the stomach.
3- Hemoglobin is a blood hemoprotein that transports oxygen from the respiratory organs to tissues, carbon dioxide from tissues to the lungs that eliminate it and also participates in the regulation of blood pH, in vertebrates and some invertebrates.
4- The ileum is the final section of the small bowel, in the digestive system.
5- The jejunum is one of the parts of the small bowel, between the duodenum and the ileum. Its function is to perform the absorption of the substances of the food chyme.
