The Digestive System

Stomach

"holding chamber" where food is stored; site of some mechanical and chemical digestion

stomach

"strechy" storage chamber where food is broken down mechanically and chemically; food becomes paste-like chyme

What are the two major components of the digestive system?

Alimentary canal, accessory organs

Pharynx

Another name for the throat; contains muscles that push food into the food tube

Is the process of swallowing voluntary, involuntary, or both?

Both voluntary and Involuntary

Oral cavity

Entrance point of food into the body; aids in moistening and breaking down food physically.

Duodenum

First and shortest region of the small intestine; where chyme (food paste) combines with digestive enzymes

Esophagus

Food tube that transports food from the oral cavity to the stomach

Pancreas

Gland that secretes enzymes for the digestion of proteins, lipids, and carbohydrates into the duodenum. Produces insulin needed for the proper uptake of glucose by cells.

Salivary Glands

Glandular secretions lubricate food; secretions contain the enzyme amylase which begins carbohydrate digestion

Where do stronger wave-like contractions occur?

In the body of the stomach

Rectum

Lower part of the colon that stores solid wastes

What are the two digestive processes?

Mechanical and Chemical Digestion

Anus

Opening through which solid wastes leave the body

Liver

Produces and secretes bile for lipid emulsification; converts glucose to glycogen.

Jejunum

Second section of the small intestine (8 ft in length); site of most digestion and absorption of nutrients.

Large intestine (colon)

Site of compaction of intestinal contents into feces; site of water and vitamin absorption.

Tongue

Skeletal muscle covered with epithelial tissue; used to manipulate food and assist in swallowing.

The component of the alimentary canal whose function is to break down food matter chemically through acid and enzymatic attack is the ?

Stomach

Gall Bladder

Stores bile and releases bile into the duodenum

Ileum

Third and final section of small intestine (about 12 ft long); additional site of some nutrient absorption

What moves bolus down the esophagus?

Wave-like contractions known as peristalis

mesentery

a double layered membrane that covers and holds abdominal organs in place

Haustral Churning process

a haustrum fills up with food remnants, contracts, and squeezes the contents into the next haustrum. While haustral churning occurs, peristalsis is also taking place.

an important function of the large intestine is to

absorb water

mastication

act of chewing food

deglutition

act of swallowing food

characteristics of large intestine

all choices are correct with the exception of c

what correctly describes the function of the liver?

all choices are correct. synthesizes bile, converts excess glucose to glycogen, filters and detoxifies blood

peristalsis

alterning contractions and reaxation of muscles in the wall of the digestive tract

What does the pancreas secrete in the small intestine?

amylase, lipase, trypsin

an enzyme found in saliva, secreted by the parotid, sublingual and submandibular glands

begins the digestion of carbohydrates

an enzyme found in saliva, secreted by parotid, sublingual, and submandibular glands..

beings the digestion of carbohydrates

Carbohydrate examples

breads, pasta, beans, rice, and fruits.

which of the following correctly describes digestion in the small intestine?

carbohydrate, protein, and lipid digestion are completed

regions of the large intestine in order from the small intestine to the anus

cecum, ascending, transverse, descending, rectum

Chief cells

cells-secrete pepsinogen will become pepsin and initiates digestion of proteins such as meat, fish and eggs.

Chemical digestion

consists of a series of reactions in which enzymes split large carbohydrate, lipid, and protein molecules into smaller molecules.

chemical digestion

digestion involving the breakdown of food particles into smaller molecules by acid/enzymes

mechanical digestion

digestion involving the physical breakdown of large food pieces into saller ones

amylase

digests carbohydrates

intestinal juice

digests carbohydrates and proteins

lipase

digests lipids

trypsin

digests proteins

which of the following organs is not an accessory structure of the digestive system? a. pancreas b. gall bladder c. salivary glands d.duodenum

duodenum

Bile directly assists in the

emulsification of lipids

salivary gland

exocrine glands that deliver secretions into the oral cavity; begin carbohydrate digestion

bile

fluid produced by the liver that functions to break down large fat globules

hard palate

forms the superior boundary of the oral cavity; made of fused maxillae

What occurs in the stomach in order to mix food with gastric juices and produce a paste-like substance called chyme?

gentle, rippling contractions

In the large intestine, undigested food will move along a series of ________________?

haustral pouches

the precursor substance, pepsinogen, is converted to pepsin

in the presence of HCI

What are the 5 major functions of the digestive system?

ingestion, movement, digestion, absorption, defecation

What are two hormones the pancreas produces?

insulin and glucagon

ingestion

intake of food in mouth

largest gland and internal organ of body

liver

synthesis and secretion of bile is a major digestive function of the a. liver b. gal bladder c.pancreas d.duodenum e. stomach

liver

large intestine

major site for the absorption of water and some vitamins; short, final segment of the alimentary canal

absorption

movement of small nutrient molecules to the circulatory system for transport to cells

esophagus

muscular tube that connects and delivers food from the oral cavity to the stomach.

teeth

needed to tear and grind food mechanically in the process of mastication

path food passes through while moving within and out of the digestive tract

oral cavity, pharynx, esophagus, stomach, small intestine, duodenum, jejunum, Ileum, large intestine, ascending, transverse colon, descending, sigmoid colon, rectum, anus

which of the following digestive juices contains enzymes that chemically digest carbohydrates, fats, and proteins?

pancreatic juice

chyme

paste-like stomach contents consisting of partially digested food and gastric juices

passage of a bolus of food down the food tube is assisted by

peristalsis and gravity

emulsification

physical breakdown of large fat globules into smaller ones

uvula

projection of the soft palate that extends downward; helps prevent the movement of food and water from the oral cavity up into the nasal cavity

which of the following correctly describes chemical digestion in the stomach?

protein digestion is initiated

digestive juice that contains enzymes that digest carbohydrates, but not fats and proteins

saliva

Parietal cells

secrete HCI

Mucous cells

secrete mucus which prevents pepsin from digesting the stomach lining

What occurs as chyme reaches the pyloric region of the stomach?

several mL of food will be forced through the pyloric sphincter.

which structure is the site of the most digestion and nutrient absorption?

small intestine

which structure is not a component or accessory structure of the digestive system?

spleen

which structure is not a component or accessory structure of the digestive system? a. liver b. gall bladder c. pancreas d. salivary glands e. spleen

spleen

the component of the alimentary canal whose function is to break down food matter chemically through acid and enzymatic attack is the

stomach

gall bladder

stores bile which is used to break down large fat globules into smaller droplets

Examples of Accessory organs

teeth, salivary glands, liver, pancreas, and gall bladder

hydrolosis

the addition of water to large food molecules to break binds and form smaller molecules

where do most digestion and nutrient absorption processes occur?

the duodenum and jejunum regions of the small intestine.

Mechanical digestion

the physical breakdown of food by teeth (mastication) and the churning of food by smooth muscles of the stomach and small intestine.

All of the following are functions of the oral cavity except

to absorb nutrients

all of the following are functions of the oral cavity except

to absorb nutrients

which chemical would you not expect to be actively involved in the digestion of fried potatoes?

trypsin

Alimentary Canal

tube that begins at the mouth (oral cavity) and extends to the anus. -measures approximately 30 feet (9m) in length

feces

undigested food products combined with water and bacteria that are discharged from the rectum

How does absorbed nutrients move to the liver?

via hepatic portal veins

When does the voluntary phase of swallowing occur?

when the ball of food known as a bolus is forced in the pharynx by the tongue.

When does the involuntary phase of swallowing occur?

when the pharyngeal muscles contract and force the bolus into the esophagus.