Chapter 9: Digestive System

What are the functions of the digestive system?

ingestion, digestion, movement, absorption, elimination

Ingestion

taking in food and nutrients through the mouth 

• ex. eating 

Digestion

 breaking down the food with teeth and salivary glands → taking it to esophagus 

• ex. chewing and swallowing 

Movement

 muscular contractions let the food move down the digestive tract 

• ex. peristalsis 

Absorption

 absorbing the digested nutrients to send it into the bloodstream 

• ex. sponging nutrients 

Elimination

undigested and remainder of substances are eliminated from the body → sent to the anus 

• ex. using the bathroom

peristalsis

a series of wave-like muscle contractions that move food and waste products through the digestive tract

 What is the pathway of food through the digestive system?

Mouth, Esophagus, Stomach, Small Intestine, Large Intestine

Bolus

food entering mouth, chewing and mixing with saliva 

Chyme

formed from bolus + stomach acid

Feces

formed from undigested material and chyme

Accessory Organs/Glands

Salivary Glands, Teeth, Tongue, Liver, Gall Bladder, Pancreas

Liver

processes and stored nutrients 

Gall Bladder

processes and stored nutrients 

Pancreas

Produces insulin + secretes it after eating it

Teeth

break down food and nutrients during digestion

Tongue

eating and speaking

Salivary Glands

secretes saliva; digestive enzyme

What is an ulcer? How can you get one?

An ulcer is an opening in the stomach lining. This can be caused by stress, infection, excessive acid production 

What does nutrition mean?

the process where organisms intake nutrients and food to produce energy to boost function

Crohn's Disease

a chronic inflammatory bowel disease (IBD) that can affect any part of the digestive tract, from the mouth to the anus

Gastritis

Inflammation of stomach lining 

Gastroparesis

a condition where the stomach muscles don't function properly, slowing or stopping the movement of food from the stomach to the small intestine

How is diabetes type 2 linked to obesity? Why is this an issue?

Insulin Resistance →excess body fat, cell destruction and mobility issues result from this 

2. What do calories tell you about the foods you eat?

how much energy you get from this food 

Why are carbohydrates, lipids, and proteins important?

they all provide energy, storage, and insulation for bodily functions

carbohydrates

sugar molecules/glucose - fuel for activity/can also be storage 

• example: grains, fruits, vegetables 

Lipids

• organic molecules, energy storage 

  • example: fats, oils, waxes 

proteins

• cell structure, function and regulation 

  • example: meat, dairy, seeds

Lipid Soluble

• dissolve in oils and fats

  • example: vitamins A, D, K, E, Estrogen, Testosterone

Water Soluble

• dissolves in water 

  • example: Vitamins C and B, amino acids, insulin

Why are minerals important like calcium, sodium, potassium, etc. 

They help develop strong teeth and bones, as well as regulate nerve function 

Know ways to be healthy regarding nutrition

Have a balanced diet, reduce artificial food intake, drink a sufficient amount of water