AP BIOLOGY

Detailed explanation-1: -Many birds swallow sharp pebbles and grit and hold these rocks in a muscular part of their stomachs called the gizzard. The gizzard contracts and grinds the gastroliths against each other and against the food that the bird has swallowed (remember that birds have to swallow each bite whole).

Detailed explanation-2: -Birds have a two part stomach, a glandular portion known as the proventriculus and a muscular portion known as the gizzard.

Detailed explanation-3: -This is defined as the apparatus that allows the bird to prehend and swallow feed, a muscular channel (esophagus, proventriculus, gizzard, intestine) that transports the feed through the body, the salivary glands and pancreas that contribute digestive enzymes, the liver that secretes bile for fat digestion.

Detailed explanation-4: -Many animals like crocodiles and seals eat rocks to help with digestion-they’re called gastroliths.