Human Anatomy U10 - Digestive

What is a fistulated cow?

A cow with a passageway connecting the cow’s stomach (rumen) to the outside

What is a scurvy?

Disease of malnutrition that’s caused by a lack of vitamin C

Symptoms of scurvy

Bleeding gums, swelling, slow-healing wounds, bruising

What happens to collagen in scurvy?

The body can no longer produce it

Function of the digestive system

Breakdown of food (mechanical and chemical), absorption of nutrients

Chemical digestion

Saliva, stomach acid

What does the digestive system consist of?

Alimentary canal + accessory organs

Mucosa

Carries absorption, protects tissues

Sub-mucosa

glands, blood vessels, nerves

Muscular

Smooth muscle that pushes food

Serosa

Lubricates surfaces

Order of tissues of alimentary canal from inside to outside

Mucosa → sub-mucosa → muscular → serosa

Purpose of villi in the small intestine

Increase surface area for absorption of nutrients

Celiac disease

Affects the villi where they cannot absorb nutrients; often triggered by gluten

Mixing movements

Mix food with digestive juices

Peristalsis

Pushes food down the tube (involuntary)

Mouth

Begins digestion by chewing and mixing with saliva

Frenulum

Connects the tongue to the floor of the mouth

Tongue

Moves food while chewing

Palate

Forms roof of oral cavity (hard and soft)

Uvula

Located at the back of the mouth, helps prevent larger pieces from coming through

Palatine tonsils

Organs that protect against infection & part of the immune system

Palatine tonsils location

Back of the mouth/throat

Tonsillitis

Inflammation of the tonsils that can cause sore throat & fever (hard time swallowing)

Incisors

Front four teeth that you see

Cuspids

Canines (sharp anterior teeth)

Bicuspids

Premolars, first two posterior teeth

Molars

Last three teeth; last ones (3rd) are called wisdom teeth → vestigial

Crown

Part of the tooth that projects above the gums

Root

Part of the tooth that’s anchored to the alveolar process of the jaw

Enamel

Part of the tooth that’s made of calcium, hardest substance in the body

Dentin

Similar to bone, surrounds tooth’s central cavity

Root canal

Part of the tooth that contains blood vessels and nerves (inside)

What is the root canal procedure?

Cleaning the infected canal to repair and save it

Wisdom teeth

Molars that come in during young adulthood; often need to be removed because they’re vestigial & grow out poorly

Amylase

Breaks down starch into sugars

Three salivary glands

Parotid, submandibular, sublingual

3 sections of the pharynx

nasopharynx, oropharynx, laryngopharynx

Pharynx

Space in the back of the throat → pathway for food/air; choking can happen there

Dysphagia

Difficulty swallowing

Esophagus

Moves food to stomach

Esophageal hiatus

Where esophagus penetrates the diaphragm

Cardiac (esophageal) sphincter

Entrance to the stomach