Digestive System Study Guide

Flashcards covering key concepts from the digestive system study guide.

What are the four layers of the wall of the alimentary canal?

Mucosa, Submucosa, Muscularis, Serosa.

What is the function of the mucosa in the alimentary canal?

Secretes mucus, absorbs nutrients, and protects tissues.

What are the names and functions of mixing and propelling movements in the digestive tract?

Mixing movements are segmentation; propelling movements are peristalsis.

Where are the parotid salivary glands located and what do they secrete?

Near the ears; secretes watery, amylase-rich saliva.

What is a bolus?

A soft mass of chewed food ready for swallowing.

What is the primary function of the esophagus?

Transports food from the pharynx to the stomach via peristalsis.

What is the structure and function of the stomach?

J-shaped muscular organ with gastric folds; stores food, initiates protein digestion, mixes chyme.

What do parietal cells secrete and what is their function?

Secrete HCl & intrinsic factor, which activates pepsinogen and absorbs B12.

What is the main component of gastric juices?

HCl, pepsinogen, and mucus; produced by gastric glands.

What does pepsin do?

Digests proteins into peptides.

What are the four types of digestive enzymes found in pancreatic juice and their functions?

Amylase (breaks down starch), Lipase (breaks down fats), Trypsin (breaks down proteins), Nucleases (breaks down nucleic acids).

What is the functional unit of the liver?

Lobule.

What does the liver produce and where is it stored?

Produces bile; stored in the gallbladder.

What are the components and functions of bile?

Bile salts, bile pigments, cholesterol, electrolytes; emulsifies fats for digestion.

Name the three parts of the small intestine and their functions.

Duodenum (digestion), Jejunum (absorbs nutrients), Ileum (absorbs remaining nutrients).

What do intestinal villi do?

Increase surface area for absorption.

What is the function of the mesentery?

Supports intestines and holds blood vessels/lymphatics.

What are the three types of digestive enzymes of the intestinal mucosa and their functions?

Peptidase (breaks peptides into amino acids), Sucrase (breaks sucrose into glucose/fructose), Lactase (breaks lactose into glucose/galactose).

Where does the majority of nutrient absorption occur in the small intestine?

Jejunum.

What are the functions of the large intestine?

Absorbs water, forms feces, houses gut bacteria.

What are the four parts of the colon?

Ascending, Transverse, Descending, Sigmoid.

What is the effect of a peristaltic rush?

Causes intense peristalsis leading to diarrhea.

What are the five sphincters in the digestive system?

Upper esophageal, Lower esophageal, Pyloric, Ileocecal, Anal.

How does mechanical digestion enhance chemical digestion?

It increases the surface area for enzymes.

Where does protein digestion begin?

In the stomach (by pepsin).

Where does carbohydrate digestion begin?

In the mouth (by salivary amylase).

What enzyme breaks down large starch molecules?

Amylase.

Describe the structure and function of the pharynx.

Muscular passage connecting mouth to esophagus and trachea; involved in swallowing.

What covers the trachea during swallowing?

Flap that prevents food from entering trachea.

What is the difference between a nutrient and an essential nutrient?

Nutrient: Needed for body function; Essential: Must be obtained from diet.

What are the six classes of nutrients?

Carbohydrates, proteins, fats, vitamins, minerals, water.

What does BMI stand for and what does it measure?

Body Mass Index; measures weight relative to height.

What are the three types of fat?

Subcutaneous, Visceral, Intramuscular.

Which type of fat is considered more dangerous?

Visceral fat.

What are the three ways that energy is expended?

BMR (energy at rest), Physical Activity (energy for movement), Thermic Effect (energy for digestion).

What does BMR stand for?

Basal Metabolic Rate; measures energy needed at rest.

What are the body processes that use energy?

Breathing, circulation, temperature regulation, digestion, cellular activity.

What are the four types of carbohydrates?

Monosaccharides, Disaccharides, Polysaccharides, Fiber.

What is insulin and its functions?

Hormone from pancreas; regulates blood glucose by promoting uptake into cells.

What are the three fates of glucose in the body?

Used for energy, stored as glycogen, converted to fat.

What are the three types of triglycerides?

Saturated, Unsaturated, Trans fats.

What are the six functions of fat?

Energy source, Insulation, Protection, Vitamin absorption, Cell structure, Hormone production.

What are the monomers for proteins, carbohydrates, and lipids?

Proteins: Amino acids, Carbohydrates: Monosaccharides, Lipids: Fatty acids and glycerol.

What is the difference between essential and nonessential amino acids?

Essential: Must be eaten; Nonessential: Made by the body.

What is a complete protein? Give two examples.

Contains all 9 essential amino acids; Examples: Eggs, quinoa.

What is the calorie content per gram of carbohydrates, fats, and proteins?

Carbohydrates: 4 kcal, Fats: 9 kcal, Proteins: 4 kcal.

How many calories are in a product containing 37 g carbohydrates, 8 g fat, and 3 g protein?

232 kcal.

What are the ABCD’s of a nutritional assessment?

Anthropometrics (height, weight), Biochemical (blood, urine tests), Clinical (physical signs), Dietary (food intake).

What is malnutrition and some factors leading to it?

Poor nutrition from lack or excess of nutrients; Factors: Poverty, illness, poor diet, digestive disorders.