FINALS: THE DIGESTIVE SYSTEM

ingestion, digestion, absorption, defecation

functions of digestive system?

ingestion

placing of food or fluid into the mouth

buffers

neutralizes acid to prevent tooth decay

propulsion

Movement of foods from one region of the digestive system to another.

peristalsis

alternating waves of contraction and relaxation that squeeze food along the Gi tract

segmentation

movement of materials back and forth to foster mixing in the small intestine

digestion

occurs when enzymes break chemically down large molecules into their building blocks.

carbohydrates

are broken down to simple sugars (like glucose).

proteins

are broken down to amino acids.

fats

are broken down to fatty acids and glycerol.

mechanical digestion

involves physically breaking down food substances into smaller particles to more efficiently undergo chemical digestion.

mechanical digestion

This begins in the mouth with chewing or mastication and continues with churning, mixing actions in the stomach, and segmentation in the small intestine

chemical digestion

is to further degrade the molecular structure of the ingested compounds by digestive enzymes into a form that is absorbable into the bloodstream.

small intestine

all digestion is completed in the?

stomach

where does protein digestion begins?

small intestine

where does fat digestion begins?

mouth

where does chemical digestion of carbohydrates begins?

absorption

simple molecules resulting from chemical digestion are absorbed into the blood or lymph.

absorption

These molecules pass through the cell membranes (mucosal cells) of the lining in the small intestine anc enter the bloodstream or lymphatic capillaries for distribution throughout the body.

defecation

Elimination of indigestible substances from the GI tract in the form of feces

teeth, tongue, salivary glands, pancreas, liver, gallbladder

accessory digestive organs includes?

tongue

Is a muscular organ in the mouth.

mouth

Mastication (chewing) of food

mouth

Taste buds on the tongue allow for taste

mouth

Tongue mixes masticated
food with saliva

mouth

Tongue Initiates swallowing

tongue

is covered with moist, pink tissue called mucosa. In the back of the mouth, the tongue is anchored into the hyoid bone.

tongue

is vital for chewing and swallowing food, as well as for speech.

sweet, sour, bitter, salty

what are the four common taste?

fungiform, circumvallate, foliate, filiform papillae

tongue is covered with four kinds of papillae, what are these four?

gustatory papillae

this papillae contains taste buds and is called?

filiform papillae

it is a coating mechanism for your tongue

filiform

it does not contain taste buds

pharynx

Serves as a passageway for foods,

fluids, and air

pharynx

the back of the throat

15cm

pharynx is approximately what long?

larynx

passage for air, closes when we swallow.

epiglottis

flap of cartilage
closes trachea (windpipe) when swallowing food travels down esophagus

peristalsis

involuntary muscle contractions to move food along

esophagus

Passageway for food only (respiratory system branches off after the pharynx

esophagus

Conducts food by peristalsis (slow rhythmic squeezing) to the stomach, Pushes food to Stomach

esophagus

About 10 inches long, Runs from pharynx to stomach through the diaphragm

stomach

it serves as food storage and it has a pH 2

lower esophageal sphincter

As food reaches the end of the esophagus it enters the stomach through a muscular valve called the?

lower esophageal sphincter

is a bundle of muscles at the low end of the esophagus, where it meets the stomach.

lower esophageal sphincter

it is closed, it prevents acid and stomach contents from traveling. backwards from the stomach

cardia

is the first part of the stomach below the esophagus.

cardia sphincter

it is a thin ring of muscle that helps to prevent stomach contents from going back up into the esophagus.

pylorus

is the part of the stomach that connects to the small intestine

rugae

When the stomach is empty, the inside has small folds called ?

rugae

allow the stomach to expand to accommodate large meals. It also grip the food inside the stomach to help physically break it down

pyloric sphincter

is a band of smooth muscle at the junction between the pylorus of the stomach and the duodenum of the small intestine,

pyloric sphincter

It plays an important role in digestion, where it acts as a valve to controls the flow of partially digested food from the stomach to the small intestine.

antrum

holds the broken-down food until it is ready to be released into the small intestine.

pyloric antrum

what is the other term for antrum?

stomach

Mechanically and chemically breaks down food

2 to 4 hrs

how many hours is food stored in the stomach?

gastric juices

Secreted by the stomach.

gastric juices

Acidic (pH 1.5-2.5) (HCI).

pepsin

an enzyme that breaks down large proteins into amino acids.

chyme

Food is further broken down into a thin liquid called?

serosa, muscularis, sub-mucosa, mucosa

The wall of alimentary canal consists of four layers?

serosa

is the outermost layer consists of small amount of connective tissue.

small intestine

The body's major digestive organ

small intestine

Longest portion of the alimentary tube (2-4 m, or 7-13 feet, in a living person

small intestine

Site of nutrient absorption into the blood

small intestine

Muscular tube extending from the pyloric sphincter to the ileocecal valve

small intestine

Suspended from the posterior abdominal wall by the mesentery

duodenum, jejunum, ileum

what are the subdivision of small intestine?

duodenum

9 to 10 inc, digestive enzymes & bile

carbohydrates

Pancreatic amylase in the duodenum continues breaking down carbohydrates into simple sugars.

protein

Enzymes like trypsin and chymotrypsin break down protein into smaller peptides and amino acids.

lipids

Bile helps emulsify fats, making it easier for lipase (from the pancreas to digest them Into fatty acide and glycerol.

jejunum

8 ft long, finalize food digestion

ileum

12 feet long, absorptive fnx, connects with large intestine

duodenum

1st section of small intestines, acid food from stomach, mixes with digestive juices

pancreas, liver, gallbladder

duodenum is from?

small intestine

Most chemical digestion takes place here.

small intestine

where does chemical digestion begins?

enzymes

produced intestinal cells and pancreas carries to are duodenum the pancreatic ducts by

large intestine

Larger in diameter, but shorter in length at 1.5m, than the small intestine

large intestine

Extends from the ileocecal valve to the anus

cecum, appendix, colon, rectum, anal canal

what are the subdivision of large intestine?

solid materials

pass through the large intestine, these are undigestible solids (fibers).

rectum

solid waste exists the body

cecum

saclike first part of the large intestine

appendix

Hangs from the cecum

appendix

Accumulation of lymphoid tissue that sometimes becomes inflamed

ascending

travels up right side of abdomen and makes a turn at the right colic (hepatic) flexure

transverse

travels across the abdominal cavity and turns at the left colic (splenic) flexure

descending

travels down the left side

sigmoid

S-shaped region; enters the pelvis

escherichia coli

it produce vitamins k and b

rectum

last section of colon or large intestine

anal canal

Terminal segment of the large intestine, between the rectum and anus, located below the level of the pelvic diaphragm.

anal canal

It is located within the anal triangle of the perineum, between the right and left ischioanal fossa.

anal canal

The anus is the aperture at the terminal portion of the anal canal.

colonoscopy

is a medical procedure involving the endoscopic examination of the large bowel and the distal portion of the small bowel.

colonoscopy

This examination is performed using either a CCD camera or a fiber optic camera, which is mounted on a flexible tube and passed through the anus.

teeth

are hard bony appendages that are borne on the jaws and serve especially for the prehension and mastication (chewing) of food