Digestive System

What is the first step in the digestive tract where food is mechanically and chemically processed?

Mouth, where teeth, tongue, and saliva begin the digestion process.

What enzymes are found in saliva that aid in chemical digestion?

Amylase and lipase.

What is the function of the pharynx in the digestive system?

It serves as a pathway for food to travel from the mouth to the esophagus.

What are the three types of cells in the stomach and their functions?

Mucus cells (protect), parietal cells (produce HCl), chief cells (produce pepsinogen).

What is the main function of the duodenum?

Chemical digestion and the start of nutrient absorption.

What is the role of the jejunum and ileum in the digestive process?

Absorption of nutrients.

What is the cecum and its importance in digestion?

It is the beginning of the large intestine that collects waste.

What does the colon absorb during digestion?

Electrolytes, vitamins, water, and fatty acids.

What are the functions of the soft palate during swallowing?

Separates digestive and respiratory tracts during swallowing and aids in suckling in infants.

How many total teeth are there in an adult human mouth?

32 total teeth.

What are the roles of incisors, canines, premolars, and molars?

Incisors grasp and break food, canines tear and shred food, premolars grind food, molars crush food.

Describe the steps of the swallow reflex.

Soft palate flips up, epiglottis closes over larynx, esophagus relaxes, peristalsis pushes food down to stomach.

What type of epithelium lines the esophagus?

Non-keratinized stratified squamous epithelium.

What are the four layers of the alimentary canal?

Mucosa, submucosa, muscular, adventitia.

What is the function of blood vessels and lymph lacteals in the digestive system?

Nutrient absorption and removal.

How do peristaltic movements work?

Longitudinal muscles shorten the tube while circular muscles constrict it.

What are the primary regions of the stomach and their functions?

Cardia (produces mucus), fundus (storage/chemical digestion), body (mixes food), pylorus (passes chyme to small intestine).

What is Chyme?

Partially digested food mixed with gastric juices in the stomach.

What role do pyloric glands play in digestion?

They release neutralizing mucus and pass chyme to the small intestine.

List the functions of the small intestine.

Chemical digestion, nutrient/water absorption, waste removal, bacterial barrier.

What are villi and microvilli, and their roles in the small intestine?

They maximize surface area for digestion and absorption of nutrients.

What is the primary difference between the duodenum and the jejunum/ileum?

Duodenum performs chemical digestion while jejunum/ileum are primarily for nutrient absorption.

What does the pancreas produce for digestion?

Lipases, nucleases, amylases, proteases, and bicarbonate ions.

What is the function of bile?

Emulsifies fats/lipids.

What is the role of the gallbladder in digestion?

Stores bile.

What is the process of nutrient processing in the liver?

Processes all nutrients from the intestines, passing through hepatic portal vein.

What is the primary function of the cecum?

Collects waste left over after nutrients are absorbed.

What is the role of the appendix?

Houses beneficial bacteria.

What occurs in the large intestine?

Reabsorbs water, vitamins, and fatty acids and houses bacterial colonies.

What role do carbohydrates play in the body?

They provide energy.

What do lipids contribute to in the body?

They are important for structure and communication.

What are essential nutrients?

Nutrients that are necessary for the body but cannot be synthesized by it.

What is the difference between saturated and unsaturated fatty acids?

Saturated fatty acids are typically solid at room temperature, while unsaturated are liquid.

What type of proteins are most animal proteins classified as?

Complete proteins.

What defines a vitamin?

Necessary organic compounds required for various metabolic processes.

What defines minerals in terms of nutrition?

Necessary inorganic elements needed for various biochemical functions.

What nutrients are responsible for building blocks in the body?

Proteins.

How do LDL and HDL differ in their role in human health?

LDL carries cholesterol to tissues, while HDL removes excess fat and cholesterol.

What is a complete protein?

A protein that contains all essential amino acids.

What is an incomplete protein?

A protein that does not contain all essential amino acids.