Week 1 - Digestive System

• Mucosa • Submucosa • Muscularis • Serosa

Absorption and secretion`

Loose connective tissue to allow the mucosa to move flexibly during peristalsis. Also contains blood vessels, lymphatic vessels, and nerves

To aid in propelling nutrients in a uniform direction from the lumen to the submucosa.

Provides a partition between the internal organs and the abdominal cavity. Cells of the serous layer secrete a serous fluid that provides lubrication to reduce friction

Epithelium and supporting loose connective tissue

Connective Tissue

Smooth muscle

Epithelial layer and a thin connective tissue layer which reduces the friction from muscle movements

• Ingestion • Motility (Propulsion) • Mechanical digestion • Chemical digestion • Absorption • Defecation

Creating a bulk flow of nutrients from the outside world into your tissues (eating/drinking)

Mechanism of swallowing (voluntary action), then it’s quickly turned over to the involuntary process of Peristalsis - The smooth muscles of the walls of the digestive organs take turns contracting and relaxing to squeeze food through the lumen of the alimentary tract. Waves of Peristalsis continue through the esophagus, stomach and intestines, and they’re strong

• More smooth muscle segments push the food back and forth to keep crumbling it up • The goal is to increase the surface area of that bite of food by breaking it down into increasingly tiny pieces, to prepare it to encounter more enzymes

• Process of digestion only occurs when the main action becomes more chemical then mechanical • Liver, Pancreas and Gallbladder secrete enzymes into the alimentary canal, where they ambush the food and break it down into its most basic chemical building blocks

• Digestion allows for absorption for those nutrients (fatty acids, sugars, amino acids) as they pass from the small intestine into the blood, by both active and passive transport • Once those nutrients are absorbed by our cells, we can use the energy inside of them, or use them to build new tissues :: ABSORPTION OF THE NUTRIENTS IS THE GOAL OF THE ENTIRE PROCESS

Indigestible substances like fiber are escorted out of the body (pooping/defecation)

• Right hypochondriac • Right Lumbar • Right Iliac (Inguinal) • Epigastric • Hypogastric • Umbilical • Left hypochondriac • Left lumbar • Left Iliac

• Right upper (RUQ) • Right lower (RLQ) • Left Upper (LUQ) • Left Lower (LLQ)

• Visceral layer • Peritoneal cavity • Parietal layer

Organs

Serous fluid

The abdominopelvic cavity

• Taste • Manipulates food for chewing • Aids swallowing • Articulates speech

Plague accumulates forming a stony-hard, calcified deposit between the gum & teeth allowing a gap for bacteria to cause infection which in return could cause chronic inflammation which increases the risk of heart disease and stroke