Campbell Biology Chapter 41 Digestion Terms

Front 1

absorption

Back 1

The third stage of food processing in animals: the uptake of small nutrient molecules by an organism's body.

Front 2

alimentary canal

Back 2

A digestive tract consisting of a tube running between a mouth and an anus; also called a complete digestive tract.

Front 3

amino acid

Back 3

An organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of polypeptides.

Front 4

amylase

Back 4

An enzyme in saliva that hydrolyzes starch (a glucose polymer from plants) and glycogen (a glucose polymer from animals) into smaller polysaccharides and the disaccharide maltose.

Front 5

appendix

Back 5

A small, finger-like extension of the vertebrate cecum; contains a mass of white blood cells that contribute to immunity.

Front 6

bile

Back 6

A mixture of substances that is produced in the liver but stored in the gallbladder and that enables formation of fat droplets in water as an aid in the digestion and absorption of fats.

Front 7

bolus

Back 7

A lubricated ball of chewed food.

Front 8

bulk feeder

Back 8

An animal that eats relatively large pieces of food.

Front 9

carnivore

Back 9

An animal that mainly eats other animals.

Front 10

cecum

Back 10

The blind pouch at the beginning of the large intestine.

Front 11

chylomicron

Back 11

A small globule that transports lipids. Chylomicrons are composed of fats mixed with cholesterol and coated with proteins.

Front 12

chyme

Back 12

The mixture of partially digested food and digestive juices formed in the stomach.

Front 13

colon

Back 13

The largest section of the vertebrate large intestine; functions in water absorption and formation of feces.

Front 14

complete digestive tract

Back 14

A digestive tube that runs between a mouth and an anus; also called an alimentary canal.

Front 15

digestion

Back 15

The second stage of food processing in animals: the breaking down of food into molecules small enough for the body to absorb.

Front 16

duodenum

Back 16

The first section of the small intestine, where chyme from the stomach mixes with digestive juices from the pancreas, liver, and gallbladder as well as from gland cells of the intestinal wall.

Front 17

elimination

Back 17

The fourth and final stage of food processing in animals: the passing of undigested material out of the digestive system.

Front 18

enzymatic hydrolysis

Back 18

The process in digestion that splits macromolecules from food by the enzymatic addition of water.

Front 19

esophagus

Back 19

A channel that conducts food, by peristalsis, from the pharynx to the stomach.

Front 20

essential amino acid

Back 20

An amino acid that an animal cannot synthesize itself and must be obtained from food in prefabricated form. Eight amino acids are essential in the human adult.

Front 21

essential fatty acid

Back 21

An unsaturated fatty acid that an animal needs but cannot make.

Front 22

essential nutrient

Back 22

A substance that an organism must absorb in preassembled form because it cannot be synthesized from any other material. In humans, there are essential vitamins, minerals, amino acids, and fatty acids.

Front 23

extracellular digestion

Back 23

The breakdown of food in compartments that are continuous with the outside of an animal's body.

Front 24

feces

Back 24

The wastes of the digestive tract.

Front 25

fluid feeder

Back 25

An animal that lives by sucking nutrient-rich fluids from another living organism.

Front 26

food vacuole

Back 26

A membranous sac formed by phagocytosis of microorganisms or particles to be used as food by the cell.

Front 27

gallbladder

Back 27

An organ that stores bile and releases it as needed into the small intestine.

Front 28

gastric juice

Back 28

A digestive fluid secreted by the stomach.

Front 29

gastrovascular cavity

Back 29

A central cavity with a single opening in the body of certain animals that functions in both the digestion and distribution of nutrients.

Front 30

glucagon

Back 30

A hormone secreted by pancreatic alpha cells that raises blood glucose levels. It promotes glycogen breakdown and release of glucose by the liver.

Front 31

hepatic portal vein

Back 31

A large circulatory channel that conveys nutrient-laden blood from the small intestine to the liver, which regulates the blood's nutrient content.

Front 32

herbivore

Back 32

An animal that mainly eats plants or algae.

Front 33

ingestion

Back 33

The first stage of food processing in animals: the act of eating.

Front 34

chief cell

Back 34

cell that makes inactive pepsin, cells of the stomach that produce peptinogen

Front 35

parietal cell

Back 35

secretes hydrochloric acid, cell of a gastric gland that secretes hydrochloric acid and intrinsic factor

Front 36

insulin

Back 36

A hormone secreted by pancreatic beta cells that lowers blood glucose levels. It promotes the uptake of glucose by most body cells and the synthesis and storage of glycogen in the liver and also stimulates protein and fat synthesis.

Front 37

intracellular digestion

Back 37

The hydrolysis of food inside vacuoles.

Front 38

lacteal

Back 38

A tiny lymph vessel extending into the core of an intestinal villus and serving as the destination for absorbed chylomicrons.

Front 39

large intestine

Back 39

The tubular portion of the vertebrate alimentary canal between the small intestine and the anus; functions mainly in water absorption and the formation of feces.

Front 40

larynx

Back 40

The portion of the respiratory tract containing the vocal cords; also called the voice box.

Front 41

liver

Back 41

The largest internal organ in the vertebrate body. The liver performs diverse functions, such as producing bile, preparing nitrogenous wastes for disposal, and detoxifying poisonous chemicals in the blood.

Front 42

malnourishment

Back 42

The long-term absence from the diet of one or more essential nutrients.

Front 43

microvillus

Back 43

One of many fine, finger-like projections of the epithelial cells in the lumen of the small intestine that increase its surface area.

Front 44

mineral

Back 44

In nutrition, a simple nutrient that is inorganic and therefore cannot be synthesized.

Front 45

mucus

Back 45

A viscous and slippery mixture of glycoproteins, cells, salts, and water that moistens and protects the membranes lining body cavities that open to the exterior.

Front 46

notochord

Back 46

A longitudinal, flexible rod made of tightly packed mesodermal cells that runs along the anterior-posterior axis of a chordate in the dorsal part of the body.

Front 47

nutrition

Back 47

The process by which an organism takes in and makes use of food substances.

Front 48

omnivore

Back 48

An animal that regularly eats animals as well as plants or algae.

Front 49

oral cavity

Back 49

The mouth of an animal.

Front 50

overnourishment

Back 50

The consumption of more calories than the body needs for normal metabolism.

Front 51

pancreas

Back 51

A gland with the following dual functions: The nonendocrine portion functions in digestion, secreting enzymes and an alkaline solution into the small intestine via a duct; the ductless endocrine portion functions in homeostasis, secreting the hormones insulin and glucagon into the blood.

Front 52

pepsin

Back 52

An enzyme present in gastric juice that begins the hydrolysis of proteins.

Front 53

pepsinogen

Back 53

The inactive form of pepsin that is first secreted by chief cells located in gastric pits of the stomach.

Front 54

peristalsis

Back 54

(1) Alternating waves of contraction and relaxation in the smooth muscles lining the alimentary canal that push food along the canal. (2) A type of movement on land produced by rhythmic waves of muscle contractions passing from front to back, as in many annelids.

Front 55

pharynx

Back 55

(1) An area in the vertebrate throat where air and food passages cross. (2) In flatworms, the muscular tube that protrudes from the ventral side of the worm and ends in the mouth.

Front 56

protease

Back 56

An enzyme that digests proteins by hydrolysis.

Front 57

rectum

Back 57

The terminal portion of the large intestine where the feces are stored until they are eliminated.

Front 58

ruminant

Back 58

An animal, such as a cow or a sheep, with an elaborate, multicompartmentalized stomach specialized for an herbivorous diet.

Front 59

salivary gland

Back 59

A gland associated with the oral cavity that secretes substances to lubricate food and begin the process of chemical digestion.

Front 60

small intestine

Back 60

The longest section of the alimentary canal, so named because of its small diameter compared with that of the large intestine; the principal site of the enzymatic hydrolysis of food macromolecules and the absorption of nutrients.

Front 61

sphincter

Back 61

A ringlike valve, consisting of modified muscles in a muscular tube, that regulates passage between some compartments of the alimentary canal.

Front 62

stomach

Back 62

An organ of the digestive system that stores food and performs preliminary steps of digestion.

Front 63

substrate feeder

Back 63

An animal that lives in or on its food source, eating its way through the food.

Front 64

suspension feeder

Back 64

An aquatic animal, such as a sponge, clam, or baleen whale, that feeds by sifting small food particles from the water.

Front 65

trachea

Back 65

The portion of the respiratory tract that passes from the larynx to the bronchi; also called the windpipe.

Front 66

undernourishment

Back 66

A condition that results from a diet that consistently supplies less chemical energy than the body requires.

Front 67

villus

Back 67

(1) A finger-like projection of the inner surface of the small intestine. (2) A finger-like projection of the chorion of the mammalian placenta. Large numbers of villi increase the surface areas of these organs.

Front 68

vitamin

Back 68

An organic molecule required in the diet in very small amounts. Vitamins serve primarily as coenzymes or parts of coenzymes.

Front 69

B1 (thiamine)

Back 69

Water soluble Vitamin
found in pork Legumes, peanuts and whole grains
Functions: Coenzymes used in removing CO2 from organic compounds

Front 70

B3 (niacin)

Back 70

Water soluble Vitamin
found in: nuts, meat, grains
Function: Component of coenzymes NAD+ and NADP+

Front 71

B9 (folic acid)

Back 71

Water soluble Vitamin
found in: green vegetables, oranges nuts, legumes, whole grains
Function: coenzymes in nucleic acids and red blood cells

Front 72

C (ascorbic acid)

Back 72

Water soluble Vitamin
found in: citrus fruits, brocoli, tomatoes
Function: used in collagen synthesis antioxidant, and production of connective tissue

Front 73

A (retinol)

Back 73

Fat soluble Vitamin
found in: dark green and orange vegetables and fruits, dairy products
Function: component of visual pigments, maintenance of epithelial tissues

Front 74

D

Back 74

Fat soluble Vitamin
found in: Dairy products, egg yolk
Function: aids in absorption and use calcium and phosphorus, bone formation

Front 75

E (tocopherol)

Back 75

Fat soluble Vitamin
found in: vegetable oils , nuts seeds
Function: antioxidant; help prevent damage to cell membranes

Front 76

K (phylloquinone)

Back 76

Fat soluble Vitamin
found in: green vegetables, tea also made by colon bacteria
Function: important in blood clotting

Front 77

What are the

Back 77

...

Front 78

Calcium (Ca)

Back 78

Mineral
found in: dairy products, dark green vegetables, legumes
function: bone format, blood clotting, nerve and muscle function

Front 79

sulfur (s)

Back 79

Mineral
Found in: proteins from many sources
Function: component of many amino acids

Front 80

potassium (K)

Back 80

Mineral
Found in : meats , eggs, legumes, whole grains, green leafy vegetables
Function: acid-base balance, water balance, nerve function

Front 81

Sodium (Na)

Back 81

Mineral
found in: table salt
Function: acid-base balance, water balance, nerve function

Front 82

Iron (Fe)

Back 82

Mineral
Found in : meats, egg, legumes, whole grains., green leafy vegetables
Function: component of hemoglobin and of electron carriers; enzyme cofactor

Front 83

Fluorine (F)

Back 83

Mineral
Found in: drinking water, tea, seafood
Function: maintenance of tooth structure

Front 84

Iodine (I)

Back 84

Mineral
Found in: seafood, iodized salt
Function: component of thyroid hormones

Front 85

Digestive tract (all)

Back 85

Oral cavity, pharynx, esophagus