Digestive System Test Flashcards
The four layers of the Digestive Tract
Serosa- outer layer
Muscle Layers- layer of muscle beneath the serosa.
Submucosa- Just beneath the mucosa.
Mucosa-innermost layer of the tract.
Function of the oral cavity
Mechanically breaks down food through mastication(chewing from teeth)
Secrets salvia from the salivary glands which help to chemically break down starch(gives the food taste)
Function of Pharynx
Propels food into the esophagus through peristalsis. Has no digestive function.
Function of the Esophagus
Conducts food through peristalsis. Muscles propel the food dowards, towards the stomach.
Function of the stomach
Acts as a storage tank for food.
Site of food breakdown.
Chemically breaks down protein due to the pepsin it secrets. Forms food into chyme.
Functions of the small intestine
Site of nutrient absorption into the blood. Has little hair like fibers of cilia that help absorb subsistence.
Divided into three sections(duodenum, jejunum, and ileum) enzymes of the pancreas are secreted into this organ to help with chemical digestion.
Functions of the large intestine
Divided into four sections that absorb water, vitamins, and electrolytes.
Eliminated indigestive food from the body as feces. Does not participate in chemical/mechanical digestion.
Function of the Rectum and Anus
Eliminates waste from human body. Does not participate in mechanical/chemical digestion.
Function of the Liver
Largest gland in the body that produces bile, detoxifies drugs/alcohol, degrades hormones, and plans a major role in metabolism.
Function of the gallbladder
A sac that stores bile from the liver by way of the cystic duct, connects to the small intestines.
Function of the pancreas
Produces a wide spectrum of digestive enzymes that break down all categories of food. Enzymes get secreted into the small intestine.
Enzymes include: amylase, trypsin, lipase, and nuclease.
Structure of the Oral Cavity
Teeth=mechanically breaks down food
Labia(lips)=protect the opening of the mouth
Hard palate=forms the anterior roof of mouth
Soft palate=forms the posterior roof of mouth)
Uvula=fleshy projection of soft palate.
Epiglottis
A flap of skin that stops food from entering the respiratory system.
Anatomy of the stomach
Regions include: the cardioesophageal sphincter( where food enters the stomach) the cardiac region(near the heart), fundus, body, the rugae(internal folds of the mucosa) and the pylorus(funnel-shaped terminal end)
The pylorus sphincter empties food from the stomach into the small intestine.
Villi
finger-like structures formed by the mucosa. Allows the small intestines to absorb nutrients.
Microvilli
small projects of the plasma membrane of villi.
Pancreatic Amylase
An enzyme helps to complete digestion of starch
Pancreatic Trypsin
An enzyme that carries out about half of all protein digestion.
Pancreatic Lipase
An enzyme that is responsible for fat digestion.
Pancreatic Nuclease
An enzyme that digests nucleic acids.
Segmental movements
mix chyme with digestive juices and aid in propelling food.
Carbohydrates
Simple sugar sources: breads, rice, passage, sweets, potatoes, and milk
Proteins
Amino acids sources: animal products(meats, fish, dairy) and legumes.
Lipids
Fatty acid sources: Saturated fats from animal products(meats), nuts, seeds, vegetable oils, and egg yolk
Ingestion
getting food into the mouth
Propulsion
moving foods from one region of the digestive system to another.
Mechanical Digestion
Mixing of food in the mouth by the tongue.
Churning food in the stomach(peristalsis/segmental)
Chemical Digestion
Enzymes break down food molecules into their building blocks.
Absorption
Passage of nutrients into the blood.
Defecation
Elimination of indigestible substances as feces.
Microbiome
the combined genetic material of the microorganisms in a particular environment
