41 Chapter Flashcards
(113 cards)
1
Q
Nutrition
A
Food being taken in, taken apart, and taken up
2
Q
Herbivores
A
Mostly eat plants or algae
3
Q
Carnivores
A
Mostly eat other animals
4
Q
Omnivores
A
Regularly consume animals as well as plants or algae
5
Q
Most animals are opportunistic feeders, eating foods outside their standard diet when their usual foods aren’t available.
A
True
6
Q
An adequate diet must satisfy three nutritional needs:
A
Chemical energy for cellular processes
Organic building blocks for macromolecules
Essential nutrients
7
Q
To build the complex molecules and animal needs to grow, maintain itself, and reproduce, an animal must obtain two types of organic precursors from its food:
A
A source of organic carbon (such as sugar) and a source of organic nitrogen (such as protein). Starting with these materials, animals can construct a great variety of organic molecules.
8
Q
Essential nutrients
A
A substance that an organism cannot synthesize from any other material and therefore must absorb in preassembled form.
9
Q
Essential amino acids
A
An amino acid that an animal cannot synthesize itself and must be obtained from food in prefabricated form.
10
Q
Essential fatty acids
A
An unsaturated fatty acid that an animal needs but cannot make.
11
Q
Vitamins
A
Are organic molecules that are required in the diet in very small amounts.
12
Q
(Dietary) minerals
A
A simple nutrient that is inorganic and therefore cannot be synthesized in the body.
13
Q
B vitamins generally act as ______________ and are ____________
A
Coenzymes, water-soluble
14
Q
Vitamin C is required for …
A
The production of connective tissue
-Is water soluble
15
Q
Fat soluble vitamins include vitamin A and vitamin D (there are more)
A
True
16
Q
Vitamin A is incorporated into…
A
Visual pigments of the eye
17
Q
Vitamin D aids in…
A
Calcium absorption and bone formation
18
Q
Sodium, potassium, and chloride are important in…
A
The functioning of nerves and muscles an in maintaining osmotic balance between cells and the surrounding body fluid.
19
Q
Malnutrition
A
A failure to obtain adequate nutrition.
20
Q
Undernutrition
A
A diet that fails to provide adequate sources of chemical energy.
21
Q
Epidemiology
A
The study of human health and disease at the population level.
22
Q
The main stages of food processing are:
A
Ingestion
Digestion
Absorption
Elimination
23
Q
Ingestion
A
The act of eating or feeding
24
Q
Digestion
A
The second stage of food processing in animals: the breaking down of food into molecules small enough for the body to absorb.
25
Enzymatic hydrolysis
A splitting process used in chemical digestion which breaks bonds through the addition of water.
26
The last two stages of food processing occur after the food is digested.
True
27
Absorption
The animal’s cells take up (absorb) small molecules such as amino acids and simple sugars.
28
Elimination
The passing of undigested material out of the body.
29
Filter feeders
An animal that feeds by using a filtration mechanism to strain small organisms or food particles from its surroundings.
30
Bulk feeder
An animal that eats relatively large pieces of food.
31
Substrate feeders
An animal that lives in or on its food source, eating its way through the food.
32
Fluid feeder
An animal that lives by sucking nutrient-rich fluids from another living organism.
33
Intracellular digestion
The hydrolysis of food inside vacuoles
34
Gastrovascular cavity
A central cavity with a single opening in the body of certain animals, including cnidarians and flatworms, that functions in both the digestion and distribution of nutrients.
A form of extracellular digestion.
35
Gastrodermis
The tissue layer that lines the gastrovascular cavity
36
Alimentary canal, or complete digestive tract
A digestive tube extending between two openings, a mouth and an anus.
37
The accessory glands of the mammalian digestive system are:
Three pairs of salivary glands
The pancreas
The liver
The gallbladder
38
Peristalsis
Alternating waves of contraction and relaxation in the smooth muscles lining the alimentary canal that push food along the canal.
39
Sphincters
A ringlike band of muscle fibers that controls the size of an opening in the body, such as the passage between the esophagus and the stomach.
40
Oral cavity
The mouth
41
Salivary glands
An exocrine gland associated with the oral cavity that secretes substances that lubricate food and begin the process of chemical digestion.
42
A reflex
An automatic reaction mediated by the nervous system
43
Saliva initiates chemical digestion while also protecting the oral cavity.
True
44
Amylase
An enzyme found in saliva that hydrolysis starch and glycogen into smaller polysaccharides and the disaccharide maltose.
45
Mucus
A viscous mixture of water, salts, cells, and slippery glycoproteins called mucins.
46
The tongue aids digestive processes by…
Evaluating ingested material and then enabling its further passage.
47
Bolus
A lubricated ball of chewed food formed by the tongue.
48
Pharynx
Throat region
49
The pharynx opens to two passageways:
The trachea
The esophagus
50
Esophagus
A muscular tube that conducts food, by peristalsis, from the pharynx to the stomach.
51
Stomach
An organ of the digestive system located just below the diaphragm that stores food and performs preliminary steps of digestion.
52
Gastric juice
A digestive fluid secreted by the stomach.
53
Chyme
The mixture of partially digested food and digestive juices formed in the stomach.
54
Hydrochloric acid (HCl)
A component of gastric juice which disrupts the extracellular matrix that binds cells together in meat and plant material.
55
The concentration of hydrochloric acid (HCl) is so high that the pH of gastric juice is about __________
2
56
Protease
A protein-digesting enzyme
57
Pepsin
An enzyme present in gastric juice that begins the hydrolysis of proteins.
58
The ingredients of the gastric juice are kept inactive until they are released into the lumen of the stomach.
True
59
The components of gastric juice are produced by three types of cells in the gastric glands of the stomach:
Parietal cells
Chief cells
Mucous cells
60
Parietal cells
A type of cell in the gastric gland of the stomach which uses an ATP-driven pump to expel hydrogen ions into the lumen. At the same time, chloride ions diffuse into the lumen through specific membrane channels of the parietal cells. It is therefore only within the lumen that hydrogen and chloride ions combine to form HCl.
61
Pepsinigen
An inactive form of pepsin.
62
Chief cells
A type of cell in the gastric glands of the stomach that releases pepsinogen into the lumen of the stomach. HCl converts pepsinogen to active pepsin by clipping off a small portion of the molecule and exposing its active site.
63
Mucous cells
Secretes mucus, which lubricates and protects the cells lining the stomach.
64
Gastric ulcers
Damaged areas of the stomach lining
65
Acid reflux (heartburn)
A backflow of chyme from the stomach into the lower end of the esophagus.
66
Small intestine
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.
67
Duodenum
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.
68
The pancreas aids chemical digestion by…
Producing an alkaline solution rich in bicarbonate as well as several enzymes. The bicarbonate neutralizes the acidity of chyme and acts as a a buffer. Among the pancreatic enzymes are trypsin and chymotrypsin, proteases secreted into the duodenum in inactive forms. In a chain reaction similar to the activation of pepsin, they are activated when safely located in the lumen of the duodenum.
69
Bile
A mixture of substances that is produced in the liver and stored in the gallbladder; enables formation of fat droplets in water as an aid in the digestion and absorption of fats.
70
Bile production is integral to one of the other vital functions of the liver: the destruction of red blood cells that are no longer fully functional. In producing, bile, the liver incorporates some pigments that are by-products of red blood cell disassembly. These bile pigments are then eliminated from the body with the feces.
71
Most digestion is completed in the duodenum. The remaining regions of the small intestine, called the __________ and _______, are the major sites for absorption of nutrients.
Jejunum, ileum
72
Large folds in the lining encircle the small intestine and are studded with finger-like projections called ________. In turn, each epithelial cell of a villus has on its apical surface many microscopic projections, or __________, that are exposed to the intestinal lumen. The many side-by-side microvilli give cells of the intestinal epithelium a brush-like appearance that is reflected in the name ____________.
villi, microvilli, brush border
73
Hepatic portal vein
A large vessel that conveys nutrient-laden blood from the small intestine to the liver, which regulates the blood’s nutrient content.
74
Chylomicrons
A lipid transport globule composed of fats mixed with cholesterol and coated with proteins. Is produced by the small intestine during the hydrolysis of fats by lipase.
75
Lacteal
A tiny lymph vessel extending into the core of an intestinal villus and serving as the destination for absorbed chylomicrons.
76
The large intestine includes:
The colon, cecum, and rectum.
77
Large intestine
The portion of the vertebrate alimentary canal between the small intestine and the anus; functions mainly in water absorption and the formation of feces.
78
Colon
The largest section of the vertebrate large intestine; functions in water absorption and formation of feces. Leads to the rectum and anus.
79
Cecum
The blind pouch forming one branch of the large intestine. The cecum is important for fermenting ingested material, especially in animals that eat large amounts of plant material.
80
Appendix
A small, finger-like extension of the vertebrate cecum; contains a mass of white blood cells that contribute to immunity.
81
Feces
The wastes of the digestive tract.
82
Rectum
The terminal portion of the large intestine, where the feces are stored prior to elimination.
83
Dentition
An animal’s assortment of teeth
84
Coprophagy
Dung eating
85
Enteric division
A branch of the nervous system which is dedicated to the digestive organs and regulates its reflexes such as churning of the stomach and peristalsis.
86
Each pancreatic islet has what types of cells?
Alpha cells, which make glucagon, and beta cells, which make insulin.
87
Diabetes mellitus is caused by …
A deficiency of insulin or a decreased response to insulin in target tissues.
88
Type 1 diabetes, or insulin-dependent diabetes
Is an autoimmune disorder in which the immune system destroys the beta cells of the pancreas.
89
Type 2 diabetes, non-insulin dependent diabetes
Is characterized by a failure of target cells to respond normally to insulin.
90
Overnourishment
Consuming more calories than the body needs for normal metabolism
91
Ghrelin
A hormone secreted by the stomach wall, triggers feelings of hunger before meals.
92
PYY
A hormone secreted by the small intestine after meals; suppresses appetite
93
Leptin
A hormone produced by adipose tissue, suppresses appetite and appears to play a major role in regulating body fat levels
94
Vitamin C Major Function
Used in collagen synthesis; antioxidant
95
Vitamin C Symptoms of Deficiency
Scurvy (degeneration of skin and teeth), delayed wound healing
96
Vitamin C chemical name
Ascorbic acid
97
Vitamin B2 Major Functions
Component of coenzymes FAD and FMN
98
Vitamin B2 Symptoms of Deficiency
Skin lesions, such as cracks at corners of mouth
99
Vitamin B2 chemical name
Riboflavin
100
Vitamin B9 Major Functions
Coenzyme in nucleic acid and amino acid metabolism
101
Vitamin B9 Symptoms of deficiency
Anemia, birth defects
102
Vitamin B9 Chemical name
Folic acid
103
Vitamin B3 Major Functions
Component of coenzymes NAD+ and NADP+
104
Vitamin B3 Symptoms of deficiency
Skin and gastrointestinal lesions, delusions, confusion
105
Vitamin B3 Chemical name
Niacin
106
Sodium (Na) Major Functions
Acid-base balance, water balance, nerve function
107
Sodium Symptoms of deficiency
Muscle cramps, reduced appetite
108
Calcium (Ca) Major function
Bone and tooth formation, blood clotting, nerve and muscle function
109
Calcium symptoms of deficiency
Impaired growth, loss of bone mass
110
Potassium (K) Major function
Acid-base balance, water balance, nerve function
111
Potassium symptoms of deficiency
Muscular weakness, paralysis, nausea, heart failure
112
Phosphorus Main function
Bone and tooth formation, acid-base balance, nucleotide synthesis
113
Phosphorus Symptoms of deficiency
Weakness, loss of minerals from bone, calcium loss
