ch 4 cont - human digestion

What is the gut microbiota?

Microorganisms living in the GI tract

Where are most gut microbes located?

Large intestine

What types of organisms make up gut microbiota?

Bacteria, viruses, fungi

What is the microbiome?

The genetic material of gut microorganisms

What is a major function of gut microbiota?

Aid in digestion of undigested food

What vitamins can gut bacteria produce?

Vitamin K and some B vitamins

How do gut microbes support the immune system?

Protect against harmful pathogens

What do gut bacteria produce from fiber fermentation?

Short-chain fatty acids (SCFAs)

Why are SCFAs important?

Provide energy and support colon health

What is dysbiosis?

Imbalance in gut microbiota

What can dysbiosis lead to?

Disease or poor health outcomes

What factors influence gut microbiota?

Diet, antibiotics, environment, lifestyle

What are probiotics?

Live beneficial microorganisms

What is the purpose of probiotics?

Improve or restore gut microbiota

Where are probiotics commonly found?

Yogurt and fermented foods

Do probiotics need to be alive to be effective?

Yes they do

What are prebiotics?

Non-digestible food components that feed beneficial bacteria

What type of nutrient are most prebiotics?

Fiber

Why are prebiotics important?

Promote growth of healthy gut bacteria

What is the difference between probiotics and prebiotics?

Probiotics are bacteria; prebiotics feed them

What is dietary fiber?

Indigestible carbohydrates from plants

Why can’t humans digest fiber?

Lack enzymes to break it down

What happens to fiber in the large intestine?

Fermented by bacteria

What is constipation?

Difficulty passing stool

What causes constipation?

Low fiber, low fluid, inactivity

How can constipation be prevented?

Increase fiber, water, and activity

What is diarrhea?

Frequent, watery stools

What causes diarrhea?

Infection, toxins, or irritation

What is a major risk of diarrhea?

Dehydration

What is heartburn?

Burning sensation from acid reflux

What is GERD?

Chronic acid reflux condition

What causes GERD?

Weak lower esophageal sphincter.

What is a peptic ulcer?

Open sore in stomach or small intestine

What bacteria commonly causes ulcers?

Helicobacter pylori

What is celiac disease?

Autoimmune reaction to gluten

What is gluten?

Protein in wheat, barley, and rye

What happens in celiac disease?

Damage to small intestine villi

What is the treatment for celiac disease?

Strict gluten-free diet

What is lactose intolerance?

Inability to digest lactose

What enzyme is lacking in lactose intolerance?

Lactase

What symptoms occur with lactose intolerance?

Gas, bloating, diarrhea

Why is the gut microbiota important overall?

Supports digestion, immunity, and nutrient production

How does diet affect gut microbiota?

Fiber-rich diets promote beneficial bacteria

Why is fiber important even though it isn’t digested?

Feeds gut bacteria and supports health