The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine may be used instead of duodenum. In mammals the duodenum may be the principal site for iron absorption.

The duodenum precedes the jejunum and ileum and is the shortest part of the small intestine, where most chemical digestion takes place. The name duodenum is from the Latin duodenum digitorum, or twelve fingers' breadths.

In humans, the duodenum is a hollow jointed tube about 10–15 inches (25–38 centimetres) long connecting the stomach to the jejunum. It begins with the duodenal bulb and ends at the ligament of Treitz.

The duodenum is largely responsible for the breakdown of food in the small intestine, using enzymes. Brunner's glands, which secrete mucus, are found in the duodenum. The duodenum wall is composed of a very thin layer of cells that form the muscularis mucosae. The duodenum is almost entirely retroperitoneal.

Frank Vincent Zappa (December 21, 1940 – December 4, 1993) was an American composer, singer-songwriter, electric guitarist, recording engineer, record producer and film director. In a career spanning more than 30 years, Zappa wrote rock, jazz, orchestral and musique concrète works. He also directed feature-length films and music videos, and designed album covers. Zappa produced almost all of the more than 60 albums he released with the band The Mothers of Invention and as a solo artist. While in his teens, he acquired a taste for percussion-based avant-garde composers such as Edgard Varèse and 1950s rhythm and blues music. He began writing classical music in high school, while at the same time playing drums in rhythm and blues bands; he later switched to electric guitar.

He was a self-taught composer and performer, and his diverse musical influences led him to create music that was often impossible to categorize. His 1966 debut album with The Mothers of Invention, Freak Out!, combined songs in conventional rock and roll format with collective improvisations and studio-generated sound collages. His later albums shared this eclectic and experimental approach, irrespective of whether the fundamental format was one of rock, jazz or classical. His lyrics—often humorously—reflected his iconoclastic view of established social and political processes, structures and movements. He was a strident critic of mainstream education and organized religion, and a forthright and passionate advocate for freedom of speech, self-education, political participation and the abolition of censorship.

Peter Griffin is a fictional character and protagonist of the animated comedy series Family Guy. He is voiced by cartoonist Seth MacFarlane and first appeared on television, along with the rest of the family in the 15-minute short on December 20, 1998. Peter was created and designed by MacFarlane himself. MacFarlane was asked to pitch a pilot to the Fox Broadcasting Company based on Larry and Steve, a short made by MacFarlane which featured a middle-aged character named Larry and an intellectual dog, Steve. After the pilot was given the green light, The Griffin family appeared on the episode "Death Has a Shadow".

Peter is married to Lois Pewterschmidt and is the father of Meg, Chris and Stewie; he also has a dog named Brian. He has worked at a toy factory and at Quahog's Brewery. Despite the suburban blue-collar routine of his life, he has had a number of remarkable experiences.

Peter's voice was inspired by a janitor that MacFarlane heard at his school. His appearance was a redesign of the protagonist Larry from MacFarlane's previous animated short films, The Life of Larry and Larry & Steve. The Peter Griffin character has received generally mixed to positive reviews from critics. He has appeared in several pieces of Family Guy merchandise, including toys, t-shirts and a video game, and has made crossover appearances in other shows, including The Simpsons, South Park, American Dad and the Family Guy spin-off The Cleveland Show.