Bio Ch 14

Front 1

from innermost to the outermost layer, list the four layers of the GI tract wall

Back 1

1. mucosa 2. submucosa 3. muscularis 4. serosa

Front 2

connective tissue layer containing blood vessels, lymph vessels, and nerves

Back 2

submucosa

Front 3

layer through which nutrients must cross to enter the blood

Back 3

mucosa

Front 4

thin outermost connective tissue layer that protects and anchors the GI tract

Back 4

serosa

Front 5

the two or three layers of smooth muscle responsible for moving food through the GI tract make up the

Back 5

muscularis

Front 6

the passage of nutrient molecules from the lumen of the GI tract into the blood or lymph vessels is

Back 6

absorption

Front 7

rhythmic contractions that propel food forward

Back 7

peristalsis

Front 8

random contraction and relaxation of short segments of smooth muscle that mix food

Back 8

segmentation

Front 9

peristalsis is especially evident in the

Back 9

esophagus

Front 10

segmentation occurs primarily in the

Back 10

small intestine

Front 11

humans have ___ deciduous/baby teeth and ___ permanent/adult teeth

Back 11

20; 32

Front 12

outer surface of a tooth that is made of calcium and phosphate; beneath this a bonelike layer; the inner cavity that contains blood vessels and nerves

Back 12

enamel; dentin; pulp

Front 13

the tongue is what kind of muscle

Back 13

skeletal

Front 14

the three pairs of salivary glands and their location

Back 14

parotid glands - near the back of the jaw in front of the ear; submandibular glands - below the lower jaw; sublingual glands - below the tongue

Front 15

four functions of saliva

Back 15

moisten food, begin the chemical digestion of carbohydrates, maintain the proper pH of the mouth, protect the teeth against bacteria

Front 16

common passageway for air and food at the back of the throat is the

Back 16

pharynx

Front 17

swallowing consists of a ___ phase, in which the tongue pushes a bolus of food into the pharynx, and an _____ phase, which is the swallowing

Back 17

voluntary; involuntary; reflex

Front 18

in the swallowing reflex, the ___ ____ rises to close off the nasal passages and the ____ bends to close off the ____ and to open the ______

Back 18

soft palate, epiglottis, trachea, esophagus

Front 19

The esophagus is a tube consisting of __ and __ muscle; connects the __ to the ___

Back 19

skeletal, smooth; pharynx, stomach

Front 20

the passage of food from the mouth to the stomach is accomplished by __ and aided by ___

Back 20

peristalsis, mucus

Front 21

thick rings of circular smooth muscle that act like valves, relaxing to open and contracting to close passageways

Back 21

sphincters

Front 22

the sphincter between the esophagus and the stomach; it opens to allow food to enter the stomach and closes to prevent stomach contents from refluxing back into the esophagus

Back 22

lower esophageal/gastroesophageal

Front 23

three functions of the stomach

Back 23

storage of food, digestion of proteins, regulation of food delivery to the small intestine

Front 24

gastric juice is a mixture of ___,____, and ____

Back 24

hydrochloric acid, pepsinogen, mucus

Front 25

hydrochloric acid produces a stomach pH of __, breaks down food by dissolving ___ tissue, and aids in digestion of ___

Back 25

2, connective, proteins

Front 26

when exposed to hydrochloric acid, pepsinogen becomes ___, which breaks down proteins into ___

Back 26

pepsin, amino acids

Front 27

why do peptic ulcers occur?

Back 27

they occur if the mucus layer of the stomach is damaged because it protects the stomach lining from acid

Front 28

a special protein secreted by the stomach that binds with Vitamin B12 tso it can be absorbed by the small intestine

Back 28

helicobaster pylori

Front 29

a watery mixture of partially digested food and gastric juice that is delivered to the small intestine every 15-25 seconds

Back 29

chyme

Front 30

the small intestine completes the digestion of __, __, and ___

Back 30

proteins, carbohydrates, lipids

Front 31

the organ of the GI tract that absorbs most (95%) of the nutrients from digestion

Back 31

small intestine

Front 32

the shortest part of the small intestine that connects to the stomach (where most digestion occurs)

Back 32

duodenum

Front 33

the longest part of the small intestine and the part where the products of digestion are absorbed

Back 33

jejunum, ileum

Front 34

The mucosa of the small intestine contains large folds covered with finger-like projections called ____, which have an outer layer of epithelial cells with even smaller ____. These structures create and increased surface area for absorption of nutrients.

Back 34

villi, microvilli

Front 35

nutrients are absorbed and transported through ____ and _____ in the submucosa of the small intestine.

Back 35

capillaries, lacteals

Front 36

Digestion of carbs begins in the __ and ends in the ___. Digestion of proteins begins in the ___ and ends in the ___. Digestion of lipids occurs only in the ___.

Back 36

mouth, small intestine; stomach, small intestine; small intestine

Front 37

The stomach can digest only __, but the small intestine can digest ___, ___, and ___

Back 37

proteins; proteins, carbs, and lipids

Front 38

secretes enzymes into the small intestine that aid in the digestion of carbs, proteins, lipids. It also releases sodium bicarbonate that neutralizes the stomach acid in chyme so the enzymes can work

Back 38

pancreas

Front 39

a substance that breaks down lipids into smaller droplets for digestion

Back 39

bile

Front 40

bile is produced by the ___ and is stored and secreted into the duodenum by the ___________

Back 40

liver, hepatic portal system

Front 41

other assorted functions of the liver

Back 41

storage of vitamins A, E, D, K; storage of glucose and glycogen; storage of iron; conversion of toxic ammonia to urea; destruction of worn out RBCs; inactivation of many chemicals

Front 42

functions of the large intestine

Back 42

absorbs nutrients, ions, and water that have not already been absorbed and to store solid waste until it is eliminated

Front 43

pouch at the beginning of the large intestine

Back 43

cecum

Front 44

extending from the cecum; small fingerlike pouch with no known digestive function

Back 44

appendix

Front 45

the majority of the large intestine; its four sections

Back 45

colon; ascending, transverse, descending, and sigmoid

Front 46

bacteria in feces are important because they produce vitamins __ and ___ that are absorbed by the large intestine

Back 46

K, B

Front 47

what two systems are important in regulating digestion?

Back 47

endocrine, nervous

Front 48

approx half of our caloric intake should come from

Back 48

carbs

Front 49

lipids are important in nutrition because

Back 49

They are components of cell membranes, tey are used in the synthesis of steroids and bile, they store energy, they cushion organs, they insulate the body, and they store several vitamins

Front 50

meat and dairy products (sat fats) ___ LDLs; plant oils and fish (unsat fats) ___ LDLs

Back 50

raise (bad); lower (good)

Front 51

synthetic hydrogenation of unsaturated fats produces ___ fats that ___ LDL cholesterol; these fats may be found in commercially baked goods, vegetable shortening and magarine

Back 51

trans; increase

Front 52

important in our diets because they are components of cell membranes, enzymes, muscles, hormones, and transport molecules

Back 52

proteins

Front 53

proteins are made of just ___ amino acids; our body can manufacture __ of these; those that we cannot manufacture and must eat are ____ amino acids

Back 53

20; 12; essential

Front 54

animal proteins

Back 54

meats, eggs, milk, soybeans

Front 55

we require ___ vitamins for normal functioning; we can produce four, which are -

Back 55

13; D, K, B, biotin

Front 56

inflammation of the liver

Back 56

hepatitis