endoderm

"The development of this story has been slow."

"The dry-stone wall used a large, flat through to support the top stones. "

"After the cow chews and swallows grass, it travels through its stomachs and then into its intestines, where nutrients are absorbed. "

"The students are developing their reading skills in their English class. "

"The delicate tissue paper wrapped the fragile antique doll. "

"The scientist studied the embryo to understand how the early stages of development occur. "

"After the first coat of paint dried, he applied another layer."

"My grandmother took a digestive enzyme supplement to help with her digestion. "

"The farmer's fields produced a bountiful harvest of tomatoes this year. "

"After many frustrating attempts, he eventually finished his school project. "

"A cat is an animal, not a plant. Humans are also animals, under the scientific definition, as we are not plants."

"The biology textbook explained that a human, being an animal developing from an embryo with three distinct tissue layers, is classified as a metazoan. "