AP BIOLOGY

Detailed explanation-1: -And if you look inside a platypus, you’ll find another weird feature: its gullet connects directly to its intestines. There’s no sac in the middle that secrete powerful acids and digestive enzymes. In other words, the platypus has no stomach.

Detailed explanation-2: -The proventriculus is the true stomach of the bird from which hydrochloric acid and pepsin (an enzyme) is secreted to aid in digestion. The gizzard is the oval organ composed of two pairs of thick red muscles. These muscles are extremely strong and are used to grind or crush the food particles.

Detailed explanation-3: -The proventriculus (also known as the true stomach) is the glandular stomach where digestion primarily begins. Hydrochloric acid and digestive enzymes, such as pepsin, are added to the feed here and begin to break it down more significantly than the enzymes secreted by the salivary glands.

Detailed explanation-4: -The chicken digestive tract is like other monogastric (single stomach) animals, such as the pig, horse, and dog, but also has its own unique differences. The most notable include the lack of teeth, crop, proventriculus, ventriculus (aka gizzard), ceca, and cloaca.

Detailed explanation-5: -Gizzard. The muscular stomach or gizzard is located immediately after the proventriculus, partly between the lobes and partly behind the left lobe of the liver.