Human Digestion Flashcards

Vocabulary flashcards covering the main steps of human digestion from the study guide.

Ingestion

Taking food into the body through the mouth.

Mechanical Breakdown

Physically breaking down food into smaller pieces (chewing in the mouth, churning in the stomach).

Chemical Digestion

Using enzymes, acids, and bile to break complex macromolecules (carbs, proteins, fats) down into simple chemical units.

Propulsion (Movement)

moving food through the digestive track via swallowing and peristalsis (wave like muscle contractions)

Absorption

Transporting tiny nutrients (like glucose, amino acids, and fatty acids) through the walls of the intestines into the blood stream

elimination (defecation)

removing undigested waste and body refuse from the body

mouth and oral cavity - mechanical

teeth chew food into smaller pieces ( mastication )

mouth and oral cavity - chemical

Salivary glands secrete salvia containing salivary amylase, an enzyme that begins breaking down complex carbohydrates into simple sugars.

Mouth and oral cavity - result

Food forms a soft mass called a bolus for swallowing

Esophagus

a muscular tube connecting the throat to the stomach, moves food down using peristalsis

Stomach - mechanical

churns food to physically mix it

stomach - chemical

gastric juice breaks down proteins

hydrochloric acid

lowers PH to kill bacteria and activate enzymes

pepsin

An enzyme activated by hydrochloric acid that breaks proteins down into smaller peptides

Mucus

protects the stomachs inner lining from being damaged by its own acid

result of stomach action

food becomes semi liquid mixture called chyme

small intenstine - Duodenum

receives chyme from the stomach and secretions from accessory organs

small intenstine - nutrient absorption

lined with microscopic finger like projections called villi and microvilli. increase surface area to absorbs nutrients into the blood.

accessory organs - liver

creates bile which breaks up fats into smaller droplets so enzymes can process them faster

Gallbladder

stores and concentrates bile before releasing it into the small intenstine

Pancreas

secrets digestive enzymes such as lipase, amylase, and trypsin and bicarbonate into small intenstine

Large intestine

Does not chemically digest food further, absorbs remaining water and electrolytes back into the body, houses vitamin K, compacts leftover indigestible waste into feces

Rectum and Anus

Rectum stores feces until elimination and anus control the release of waste from body

mechanical digestion

physically breaks down food into smaller pieces such as chewing

chemical digestion

uses enzymes and acids to break down food and turns it into nutrients

order of digestion

mouth- esophagus- stomach- small intenstine- large intestine- rectum- Anus

at the base of the esophagus there is a circular muscle called what

lower esophageal sphincter

at the lower end of the stomach there is another sphincter Or valve called the

pyloric valve

when the acidic chyme Enters the small intestine what happens with the liver

The liver manufactures a cholesterol containing fluid called bile

where is bile stored until fat enters the small intestine

gall bladder

The gallbladder contracts and release this emulsifier into the intestine and causes fat to mix with __ so that the digestive enzymes can work on it

water

The pancreas releases an alkaline chemical called __ To help neutralize the acidic chyme as it enters the small intestine

bicarbonate

The pancreas is used to breakdown carbohydrates into simple sugars called what

Pancreatic amylase

"Pancreatic lipase breaks down fats into monoglycerides and free fatty acids, while proteases break down proteins into what

amino acids

when undigested substances lead the small intestine they are partially digested in the colon by what

bacteria

Most fiber is not absorbed in the colon and is passed out as what

fecal matter

what are the two things that may be reabsorbed by the colon so that they are not lost from the body

water and minerals