ch.3 the human body: are we really what we eat?

Question 1

organization of the body

atoms

Answer 1

the smallest units of matter

atoms bond to each other to form molecules

Question 2

organization of the body

molecules

Answer 2

groups of atoms bonded in specific configurations

ex. water is H2O
carbon dioxide is CO2

Question 3

organization of the body

carbohydrates, proteins, fats, and vitamins are usually very

Answer 3

large molecules

Question 4

organization of the body

the goals of digestion

Answer 4

break these large molecules down into smaller molecules

absorb the smaller molecules into the cells of the body

Question 5

organization of the body

what is the organization of the body

Answer 5

atoms
molecules
cells
tissue
organ
organ system
organism

Question 6

organization of the body

molecules are the building

Answer 6

blocks of cells

Question 7

organization of the body

cells

Answer 7

the smallest unit of life

Question 8

organization of the body

molecules that result from the digestion of food are used to

Answer 8

build the cells of the body

Question 9

organization of the body

cell membrane

Answer 9

outer layer enclosing each cell of the body

Question 10

organization of the body

cell membrane composed of

Answer 10

two layers of phospholipids

long lipid “tails” face each other toward the interior of the membrane

phosphate “heads” line the interior and exterior surfaces of the membrane

Question 11

organization of the body

cell membrane has what embedded in the membrane

Answer 11

cholesterol and proteins

Question 12

organization of the body

the cell membrane is selectively permeable allowing it to control the

Answer 12

passage of materials into and out of the cell

Question 13

organization of the body

the cell membrane encloses the

Answer 13

cytoplasm: liquid within the cell
organelles: tiny structures that perform many different cellular functions

ex. nucleus mitochondria

Question 14

organization of the body

cells join together to form

Answer 14

tissues

Question 15

organization of the body

tissue

Answer 15

group of cells acting together to perform a common function

ex. muscle tissue
nervous tissue

Question 16

organization of the body

different tissues combine to form

Answer 16

organs

Question 17

organization of the body

organ

Answer 17

a sophisticated organization of tissues that performs a specific function

ex. stomach
heart
brain

Question 18

organization of the body

organ systems

Answer 18

groups of organs working together for a particular function

ex. gastrointestinal system

Question 19

why do we want to eat?

appetite

Answer 19

is a desire to eat that is stimulated by
* sight
* smell
* thought of food

Question 20

why do we want to eat?

hunger

Answer 20

a physiologic drive to eat that occurs when our body senses that we need food

Question 21

why do we want to eat?

hypothalamus region of the brain contains a

Answer 21

cluster of nerve cells known as the feeding center and another cluster of cells known as the satiety center

Question 22

why do we want to eat?

hypothalamus functions

Answer 22

• nerve cells in the stomach and small intestine sense food and send message to hypothalamus
• hormones relay messgaes to the hypothalamus
• amount and type of food consumes influence satiety

Question 23

why do we want to eat?

the signals that prompt us to eat include

Answer 23

• nerve receptors in the stomach, which send signals to the hypothalamus to indicate if the stomach is full or empty
• blood glucose levels, which trigger the release of hormones called insulin and glucagon

Question 24

why do we want to eat?

hormones

Answer 24

chemical produced in specialized glands that travel in the bloodstream to target organs in other parts of the body

Question 25

# why do we want to eat? some hormones stimulate hunger

Answer 25

ghrelin

Question 26

# why do we want to eat? some hormones produce a feeling of satiety

Answer 26

cholecystokinin (CCK) leptin

Question 27

# why do we want to eat? foods have differing effects on our feelings of hunger and satiety

Answer 27

* proteins have the highest satiety vaule * carbs have a lower satiety value than fats * bulky foods provide a sense of satiety * solid foods are more filling than semisolid foods or liquids

Question 28

# what happens to the food we eat? gastrointestinal (GI) tract

Answer 28

series of organs arranged as a long tube through which the food passes

Question 29

# what happens to the food we eat? the GI tract includes

Answer 29

* organs such as the stomach and intestines * spincters

Question 30

# what happens to the food we eat? sphincters

Answer 30

muscles that control the passage of material from one organ to the next

Question 31

# digestive system organs of the GI tract

Answer 31

* mouth * pharynx and esophagus * stomach * small intestine * large intestine * rectum

Question 32

# digestive system accessory organs

Answer 32

* salivary glands * liver * gallbladder * pancreas

Question 33

# organs of the GI tract mouth

Answer 33

* ingestion: food enters the GI tract via the mouth * mechanical digestion: mastication tears, shreds, and mixes food with saliva * chemical digestion: salivary amylase begins carbohydrate breakdown

Question 34

# organs of the GI tract pharynx and esophagus

Answer 34

propulsion: swallowing and peristalsis move food from mouth to stomach

Question 35

# organs of the GI tract stomach

Answer 35

* mechanical digestion: mixes and churns food with gastric juice into a liquid called chyme * chemical digestion: pepsin begins digestion of proteinds and gastric lipase begins to break lipids apart * absorption: a few fat-soluble substances are absorbed through the stomach wall

Question 36

# organs of the GI tract small intestine

Answer 36

* mechanical digestion and propulsion: segmentation mixes chyme with digestive juices; peristalic waves move it along tract * chemical digestion: digestive enzymes from pancreas and brush border digest most classes of nutrients * absorption: nutrientss are absorbes into blood and lymoh through enterocytes

Question 37

# organs of the GI tract large intestine

Answer 37

* chemical digestion: some remaining food residues are digested by bacteria * absorption: reabsorbs salts, water, and vitamins * propulsion: compacts waste into feces and propels it toward the rectum

Question 38

# organs of the GI tract rectum

Answer 38

elimination: temporarily stores feces before voluntary release through the anus

Question 39

# accessory organs salivary glands

Answer 39

produce saliva, a mixtue of water, enzymes, mucus, and other chemicals

Question 40

# accessory organs liver

Answer 40

produces bile to emulsify fats

Question 41

# accessory organs gallbladder

Answer 41

stores bile before release into the small intestine through the bile duct

Question 42

# accessory organs pancreas

Answer 42

produces digestive enzymes and bicarbonate, which are released into the small intestine via the pancreatic duct

Question 43

# digestion: the mouth digestion begins in the mouth

Answer 43

* chewing is the mechanical digestion that breaks food into smaller pieces * some chemical digestion takes place in the mouth

Question 44

# digestion: the mouth salivary amylase

Answer 44

an enzyme produced by the salivary glands that begins the chemical digestion of carbohydrates

Question 45

# digestion: the mouth the mouth

Answer 45

* chewing breaks up food and begins mechanical digestion * salivary amylase begins chemical breakdown of carbohydrates * minimal digestion takes place in the mouth

Question 46

# digestion: the mouth enzyme

Answer 46

enzyme two seperate compounds two compounds joined together new compound formed; enzyme left unchanged

Question 47

# digestion: the mouth the esophagus propels food into the stomach

Answer 47

the epiglottis covers the opening to the trachea during swallowing

Question 48

# digestion: the mouth esophagus

Answer 48

food travels from the mouth to the stomach through here

Question 49

# digestion: the mouth peristalsis

Answer 49

is the muscular contractions moving food through the GI tract

Question 50

# digestion: the mouth gastroesophageal sphincter

Answer 50

seperates the esophagus from the stomach

Question 51

# digestion: the stomach the stomach mixes, digests, stores

Answer 51

food

Question 52

# digestion: the stomach digestion in the stomach includes:

Answer 52

* extensive mechanical digestion to mix food with GASTRIC JUICE * chemical digestion of proteins and fats

Question 53

# digestion: the stomach gastric juice contains

Answer 53

* hydrochloric acid (HCl) * intrinsic factor * pepsin * gastric lipase

Question 54

# what is in gastric juice hydrochloric acid (HCl)

Answer 54

to denature proteins and activate pepsin

Question 55

# what is in gastric juice intrinsic factor

Answer 55

a protein critical to the absorption of vitamin B12

Question 56

# what is in gastric juice pepsin

Answer 56

an enzyme to digest protein

Question 57

# what is in gastric juice gastric lipase

Answer 57

an enzyme to digest fat

Question 58

# digestion: stomach chyme

Answer 58

semisolid product of mechanical and chemical digestion in the stomach

Question 59

# digestion: small intestine from the stomach chyme is slowly released through the

Answer 59

pyloric sphincter to the small intestine

Question 60

# digestion: small intestine chemical digestion continues in the small intestine using

Answer 60

pacreatic enzymes and bile

Question 61

# digestion: large intestine undigested food components move through a sphincter called the

Answer 61

ileocecal valve to the large intestine

Question 62

# digestion: large intestine in the large intestine

Answer 62

* very little digestion takes place * material is stored 12-24 hr prior to elimination * water and some nutrients are absorbed

Question 63

# digestion: accessory organs surrounding the GI tract are several accessory organs

Answer 63

* salivary glands * liver * pancreas * gallbladder

Question 64

# what are the accessory organs in digestion liver

Answer 64

produces bile which emulsifies fats

Question 65

# what are the accessory organs in digestion pancreas

Answer 65

* produces many digestive enzymes * produces bicarbonate to neutralize chyme

Question 66

# what are the accessory organs in digestion gallbladder

Answer 66

stores bile

Question 67

# absorption absorption

Answer 67

the process of taking molecules across a cell membrane and into cell of the body

Question 68

# absorption a small amount of absorption occurs in the

Answer 68

stomach

Question 69

# absorption most absorption of nutrients occurs in the 3 sections of the small intestine

Answer 69

* duodenum * jejenum * ileum

Question 70

# absorption the lining of the GI tract has special structures to facilitate absorption

Answer 70

* villi * brush border

Question 71

# special structures of lining of the GI tract to facilitate absorption villi

Answer 71

folds in the lining that are in close contact with nutrient molecules

Question 72

# special structures of lining of the GI tract to facilitate absorption brush border

Answer 72

composed of microvilli that greatly increase the surface area

Question 73

# absorption water-soluble nutrients (carb, protein, minerals, some vitamins) enter the

Answer 73

portal vein

Question 74

# absorption the portal vein transports these nutrients to the

Answer 74

liver

Question 75

# absorption fat-soluble nutrients (lipids, some vitamins) enter the

Answer 75

lymphatic vessels

Question 76

# absorption lymphatic vessels transport these nutrients directly to the

Answer 76

bloodstream

Question 77

# absorption nutrients are absorbed across the mucosal membrane and into the bloodstream or lymph

Answer 77

* passive diffusion * facilitated diffusion * active transport * endocytosis

Question 78

# the role of the neuromuscular system 2 components of the neuromuscular system regulate the activities of the GI tract

Answer 78

1. the muscles of the GI tract mix and move food----both voluntary and involuntary muscles 2. nerves control the contractions and secretions of the GI tracts--- the enteric nervous system (ENS)--other branches of the autonomic nervous system---the central nervous system (CNS)

Question 79

# GI tract disorders the lining of the stomach is designed to cope with hydrochloric acid but other regions of the

Answer 79

GI tract are not

Question 80

# GI tract disorders heartburn is caused by

Answer 80

hydrochloric acid in the esophagus

Question 81

# GI tract disorders gastroesophageal reflux disease (GERD) is a

Answer 81

chronic disease for which painful persistent heartburn is the most common symptom

Question 82

# GI tract disorders peptic ulcers

Answer 82

regions of the GI tract that have been eroded by HCl and pepsin

Question 83

# GI tract disorders what is the bacteria that contributes to the production of both gastric and duodenal ulcers

Answer 83

helicobacter pylori

Question 84

# GI tract disorders vomiting often accompanies a gastrointestinal infection such as

Answer 84

norovirus

Question 85

# GI tract disorders cyclic vomiting syndrome (CVS)

Answer 85

a chronic condition involving severe nausea and vomiting that can last for HOURS OR DAYS

Question 86

# GI tract disorders diarrhea can be caused by

Answer 86

* food intolrances * infection of the GI tract * stress * bowel disorders can lead to severe dehydration is more dangerous for CHILDREN AND ELDERLY

Question 87

# GI tract disorders constipation

Answer 87

no stool passed for 2 or more days

Question 88

# GI tract disorders irritable bowel syndrome (IBS)

Answer 88

is a disorder that interferes with normal colon function ## Footnote more common in women than in men

Question 89

# GI tract disorders: IBS symptoms of IBS include

Answer 89

* abdominal cramps * either diarrhea or constipation

Question 90

# GI tract disorders cancer can develop in any region of the

Answer 90

GI tract

Question 91

# GI tract disorders the most common cancer forms are

Answer 91

* oral cancer * pancreatic cancer * colorectal cancer

Question 92

# in depth: disorders related to foods food tolerance

Answer 92

a particular food causes numerous unpleasant symptoms

Question 93

# in depth: disorders related to foods food intolerance symptoms include

Answer 93

* gas * pain * diarrhea

Question 94

# in depth: disorders related to foods food allergy

Answer 94

hypersensitivity reaction of the immune system to a componenet in a food ## Footnote the immune system is not involved

Question 95

# in depth: disorders related to foods celiac disease

Answer 95

an autoimmune disease that is also considered a genetic disorders

Question 96

# in depth: disorders related to foods celiac disease diet

Answer 96

* complete intolerance for gluten, a protein found in wheat, rye, barley, and triticale * can damage the small intestine leading to poor absorption of nutrients * requires a diet lacking wheat, rye, barley and tritcale

Question 97

# non-celiac gluten sensitivity some individuals may have a negative GI reaction when consuming gluten but do NOT have celiac disease

Answer 97

* bloating * abdominal pain * diarrhea * possible joint pain smyptoms improve by following a gluten free diet

Question 98

# signs and symptoms of dehydration symptoms in adults

Answer 98

* thirst * light-headness * less frequent urination * dark-colored urine * fatigue * dry skin

Question 99

# sympotoms of dehydration symptoms in children

Answer 99

* dry mouth and tongue * no tears while crying * no wet diapers for 3 hrs or more * high fever * sunken abdomen eyes or cheeks * irritable or listless * skin does not rebound when pinched adn releases

Question 100

# heartburn gastric juice seeping backward through the

Answer 100

gastroesophageal sphinter is not cleared quickly or completely enough from the lower esophagus, an burns the lining