Digestive System

• Mouth
• Pharynx
• Esophagus
• Stomach
• Small Intestine
• Large Intestine
• Anus

• Alimentary Canal
• Accessory Digestive Organs

• Breaks down digested food
• Absorbs nutrients into the blood

Production of cellular energy (ATP)

Fleshy projection of the soft palate

Anterior Roof of mouth

Posterior roof of mouth

Space between lips externally and gums internally

Area contained by the teeth

Hyoid and Styloid processes of the skull by the lingual frenulum

• Palatine
• Lingual

• Nasopharnyx - not part of the digestive system
• Oropharynx - posterior to oral cavity
• Laryngopharynx - connected to esophagus

Allow food and air to pass

• Longitudinal Inner Layer
• Circular Outer Layer

Contraction of the muscle layers to move substances (like food)

• From pharnyx to stomach through diaphragm
• Only good goes through the esophagus

• Inner most layer
• Moist membrane

• Layer just beneath the mucosa
• Soft connective tissue with blood vessels

• Inner circular layer
• Outer longitudinal layer

Outer most layer - visceral peritoneum

• Submucosal Nerve Plexus
• Myenteric Nerve Plexus
• Subserous Plexus

Cardioesophageal Sphincter

Left side of abdominal cavity

• Cardiac Region - near the heart
• Fundus
• Body
• Phylorus - funnel shaped terminal end

Pyloric Sphincter

• Lesser Curvature
• Greater Curvature

• Lesser Omentum - attaches the liver to the lesser curvature
• Greater Omentum - attachers greater curvature to posterior body wall

• Stores food
• Breaks food down
• Begins breakdown of protiens
• Delivers chime to the small intestines

Simple Columnar Epithelium

Gastric Juice

Hydrochloric Acid

Gastrin

Pepsinogens - protien digesting enzymes

sticky alkaline mucous

Pits formed by folded mucosa

Body's major digestive organ that absorbs nutrients into the blood

• Duodenum - Attached to the stomach, curves around head of pancreas
• Jejunum - Attaches to the duodenem
• Ileum - Extends from jejunum to large intestine

• Enzymes mix with chime
• Bile enters from the gallbladder

Small fingerlike structures that give the small intestine more surface area.

Small projections of the plasma membrane found on absorbptive cells

• Absorptive cells
• Blood capillaries
• Lacteals (special lymphatic capillaries)

Submucosa

• DOES NOT PARTICIPATE IN DIGESTION
• Absorbs water
• Creates feces
• "Goblet cells" produce mucous to act as a lubricant

• Cecum - first part
• Appendix - lympatic tissue, hangs from cecum
• Colon
• Rectum
• Anus

• Ascending
• Transverse
• Descending
• Sigmoid (s-shaped)

Band of muscle that run along the colon

• Salivary Glands
• Teeth
• Pancreas
• Liver
• Gall bladder

• Parotid
• Submandibular
• Sublingual

• Mixture of mucous and serous fluids
• Helps form food bolus, dissolves chemicals so they can be tasted, begins starch digestion

32 teeth

Baby teeth

• Incisors
• Canines
• Premolars
• Molars

• Crown - exposed part
• Neck - region in contact with the gum
• Root - part attached to the bone

• Produce digestive enzymes, which are secreted to the duodenum
• Produce the hormones Insulin and Glucagon

• Largest gland in the body
• Located on right side under diaphragm
• Connected to gall bladder via hepatic duct
• Has 4 lobes

Liquid made of bile salts, pigment, cholesterol, phospholipids and electrolytes, produced in the liver

Sac found in the hollow foss of the liver that receives and stores bile from the cyctic duct, and sends it to the duodenum in the presense of fatty food.

• Ingestion - getting food into the mouth
• Propulsion - moving food from one region to the other
• Mechanical Digestion - chewing in mouth, churning in stomach, segmentation on small intestine
• Chemical Digestion - enzymes break down food molecules

Moving materials back and forth to aid in mixing

Simple sugars

amino acids

fatty acids and alcohols

End products of digestion are absorbed in the blood or lymph

Parasympathetic division

• Buccul phase - in the mouth, voluntary
• Pharyngeal-esophagal phase - Involuntary, all passageways exept the stomach are blocked

Neural and hormonal factors

Food presense of falling pH levels

Provids a hostile environment for microorganisms

• Pepsin - regular protiens
• Rennin - milk protien

• 4 - 6 hours
• 30ml at a time

• Digestion of starch
• Half of all protien digestion
• Fat digestion
• Neutralizes chyme
• Digests nucleic acids

• Hepatic portal vein
• Lymph

Diffusion

• Bacteria break down nutrients
• Absorbs water
• Absorbs vitamins K and B

• Sluggish Peristalsis
• 3 - 4 times a day

• Carbohydrates - plants
• Lipids - saturated/unsaturated fats & cholesterol
• Protiens - contain amino acids
• Vitamins - found in all major food groups
• Minerals - veggies, legumes, milk, meat
• Water - everything is dependant on water

• substances broken down to simpler substances
• releases energy

larger molecules built from smaller ones

Turns sugar into ATP

Produces carbon dioxide and water from cell respiration

In the liver, somtimes to make ATP

• Protiens are conserved by body cells
• Ingested protiens are turned into amino acids

• Detoxifies drugs and alcohol
• Degrades hormones
• Produces cholesterol, blood protiens
• Plays central role in metabolism

Glucose molecules converted to glycogen and stored in the liver

Glucose is released from the liver

Glucose is produced from fats and protiens

• Structural basis for steroid hormones and vitamin D
• Building block of plasma membranes
• Cannot freely circulate in the blood stream

• Amount of heat produced by the body per unit of time at rest
• Small bodies have higher BMR
• Males have higer BMR than females

• Amount of kilocalories the body must consume to fuel ongoing activities
• TMR must equal calories consumed to maintain weight
• TMR increased with bodily activity