Ch 47 Processing Food And Nutrition Flashcards
(124 cards)
1
Q
What are heterotrophs?
A
Animals that have to obtain their food by other organisms.
2
Q
What are autotrophs?
A
Animals that do not depend on other organisms to feed.
3
Q
What are nutrients?
A
Nutrients are substances in food that are used as energy source, ingredients to make up compounds for metabolic processes. And building blocks for growth in repair tissues.
4
Q
What is nutrition?
A
It’s the process of taking in and using food.
5
Q
What is malnutrition?
A
Malnutrition occurs when dietary intake is either below or above required needs.
6
Q
Is the human diet more varied than other primates?
A
Yes
7
Q
What is food processing?
A
Ingestion, digestion, absorption, and elimination.
8
Q
What is the act of feeding?
A
Selection, acquisition, and ingestion of food.
9
Q
What is ingestion?
A
Taking food into the digestive cavity
10
Q
What is digestion?
A
Breaking down the food.
11
Q
What is absorption?
A
Absorption is the passage of nutrients through the lining of the digestive tract
12
Q
What is Egestion?
A
Egestion is elimination of digested and absorbed food outside of the body.
13
Q
Are animals adapted to their mode of nutrition?
A
Yes they are. (Beaks of birds, teeth of invertebrates ..)
14
Q
What are primaryy consumers?
A
Herbivores.
15
Q
What are primary consumers?
A
Herbivores
16
Q
What are herbivores?
A
They feed directly on producers. They must eat large quantities. They have strong facial muscles, grinding teeth and long, complex digestive system to break the food down.
17
Q
What are ruminants?
A
They are hooved animals with a stomach divided into four chambers. Symbiotic bacteria and protists of first two chambers that digest cellulose and produce fatty acids. Cud is formed that’s regurgitated in animal’s mouth, rechewed and reswallowed.
18
Q
What are secondary or higher-level consumers?
A
Carnivores
19
Q
What are carnivores?
A
They are predators. They eat herbivores and other animals. They have well developed canine teeth. With a simpler digestive system
20
Q
What are omnivores?
A
They consume both animal and plant matter.
21
Q
What are suspension feeders?
A
They filter food from the water
22
Q
Do sponges nave digestive system? How do they consume food
A
They don’t have a digestive system. They filter microorganisms 1 phagocytize and digest trapped food intracellulary.
23
Q
A
24
Q
Which category of animals have gastrovascular cavity?
A
Cnidarians and flatworms.
25
What is the gastrovascular cavity?
It is a central digestive cavity with a single opening lined with cells secreting enzymes for protein's breakdown, extracellular digestion. Digestion continues in food vacuoles. Undigested material egested through the mouth,
26
What is peristalsis?
Process of movement of muscles to move the food
27
What is mucosa?
Mucosa is the inner layer of epithelium that underlies the connective tissue. It lines the lumen.
28
What is the submucosa?
It is composed of connective tissue. It contains blood, lymphatic vessels, and nerves.
29
How many layers of smooth muscle is the submucosa composed of?
Three ,Layers:
Inner submucosa muscles (oblique)
,Middle sublayer arranged circularly.
Outer sublayer arranged longitudinally.
Muscular submucosa
30
What is the outer connective tissue of the submucosa called?
The visceral peritonaeum
31
Where is the parietal peritoneum located?
It’s the connective tissue lining walls of abdominal and pelvic cavities
32
What is the peritoneal cavity?
It is where the visceral peritoneum and parietal peritoneum connect.
33
What are incisors teeth used for?
Biting.
34
What are canine teeth used for?
Tearing food.
35
What are premolars and molars used for?
Grinding.
36
What is the enamel of the teeth?
Is covers the tooth which is primarily composed of dentin.
37
What is the pulp cavity?
The pulp cavity is a connective tissue containing blood vessels, lymphatic vessels, and nerves
38
By how many pairs of glands is saliva produced?
3 pairs of glands.
39
What are the three pairs of glands that saliva is produced?
2 submendibular
2 sublingual
2 parotid glands
40
What is salivary amylase?
It is a digestive enzyme that initiates enzymatic digestion of starch into sugar.
41
What is Peritonitis?
The inflammation of the peritoneum.
42
What is the food called upon swallowing?
Bolus.
43
What is the pharynx?
The pharynx is a muscular tube serving as the hallway of both respiratory and digestive systems.
44
What is the epiglottis?
The epiglottis covers the opening of the airway (larynx) during swallowing.
45
What are the internal folds of the stomach called?
Rugae.
46
What are the two gastric glands?
Parietal Cells: secrete HCl and intrinsic factor (absorption of B12)
Chief cells: produces inactive pepsinogen.
47
How is pepsinogen converted into its active form?
Pepsinogen + HCl = Pepsin
48
What does Pepsin do?
Pepsin hydrolyzes proteins to short peptides.
49
What mechanisms protect the stomach wall?
1. Alkaline mucus secreted by gastric mucosa
2. Tight epithelia (prevent contact of gastric juice to stomach wall)
50
What happens if the stomach lining is digested?
Peptic Ulcer. Helicobacter pylori is implicated in gastric ulcers.
51
What do we call the food when it leaves the stomach
Chyme. It leaves the stomach in spurts.
52
How long is the small intestine?
5 to 6 m
53
How many regions does the small intestine have?
3 regions. The duodenum. The jejunum. The ileum.
54
Where do most chemical reactions occur in the digestive system?
In the duodenum
55
What are the chemical reactions that occur in the duodenum?
Receive secretions:
Bile from the liver
Enzymes from the pancreas
Enzymes release by epithelial cells
56
What are the folds of small intestines called?
Villi. They increase surface for digestion and absorption.
57
How many microvilli is on each epithelial cells?
600 microvilli.
58
What are the troph’s?
The steeps of each Billie (fold)
59
What is Lamina proprea?
It is the equivalent of basal lamina in epithelial membrane.
60
How many sphincters are in the digestive system?
Six
61
What is the low esophageal sphincter connected to the stomach called?
Cardiac Sphincter. Since it’s mistaken for heart burns, close to the heart.
62
What is the sphincter connecting the stomach to the duodenum called?
Piloric sphincter
63
Why are sphincters important?
They regulate the flow of substances, such as bile, urine, feces, through the body.
64
What does the liver secrete that is essential to digestion of chyme?
Bile.
65
How does Bile help in digestion?
Bile mechanically digests (detergent-like action) and aids in emulsification of fats.
66
What is Bile made up of basically?
Bile is made up of bile acids, salts, phospholipids, cholesterol, pigments, water, and electrolyte chemicals.
67
How is the bile’s acidity?
It is alkaline. It’s pH= 7-8
68
Where is Bile stored? Does its strength change?
In the gallbladder. Yes, Bile’s strength is multiplied by 5 up to 18 times in the gallbladder.
69
What are the six main vital functions of the liver?
1. Secretes bile
2. Aids in homeostasis by removing or adding nutrients to the blood
3. Converts excess glucose to glycogen stored in the liver
4. Converts excess amino acids to fatty acids and urea
5. Stores iron and certain vitamins
6. Detoxifies alcohol, drugs, etc
70
What does the pancreas do to assist the digestive system?
Secretes hormones to regulate glucose in blood.
Alkaline solution rich in bicarbonate ions and digestive enzymes
71
What are the digestive enzymes secreted by the pancreas?
Trypsin and chemotrypsin & Pancreatic lipase, pancreatic amylase, and pancreatic ribonuclease and deoxyribonuclease.
72
How many lobes does the liver have?
Four lobes
73
Where is the common bile duct?
It starts where the gallbladder and liver join and ends at the small intestines.
74
What do trypsin and chemotrypsin do?
They are proteases that degrade polypeptides to dipeptides.
75
What does pancreatic lipase do?
It degrades neutral fats.
76
What does pancreatic amylase do?
It degrades various carbohydrates.
77
What does pancreatic ribonuclease and deoxyribonuclease do?
Split RNA and DNA into free nucleotides.
78
How are carbohydrates digested?
Salivary and pancreatic amylase:
Alpha glycosidic bonds are hydrolyzed —> monosaccharides.
(Betta-glycosidic are not digested. Eg, cellulose.)
Enzymes produced by epithelial cells in small intestines break disaccharides into monosaccharides when absorbed.
79
How is trypsin activated?
By enterokinase
80
What does trypsin activate?
Chemotrypsin, carboxypeptidase, and additional trypsin
81
Where are dipeptidases produced?
Produced by duodenum that split small peptides to amino acids.
82
What are fats digested into?
To fatty acids and monoacylglycerols.
83
How do bile salts emulsify fatty acids?
Reducing surface tension
84
Where are fatty acids (triglycerides) digested?
Mainly with Duodenum by pancreatic lipase.
85
Where is gastrin produced?
By the stomach mucosal cells
86
What is the target tissue of Gastrin?
Gastric glands of the stomach
87
What does Gastrin do?
Stimulates gastric glands (Chief and Parietal) to secrete pepsinogen and HCl.
88
What triggers Gastrin release?
Distension of the stomach by food, partially digested proteins and caffeine.
89
What is the source of secretin?
Duodenum by mucosal cells.
90
What is the target tissue of secretin?
The pancreas, the liver and the stomach.
91
How does secretin act on the pancreas?
It stimulates the pancreas to secrete sodium bicarbonate, which neutralizes acid in duodenum.
92
Why is secretin released?
Acidic chyme acting on mucosa of duodenum.
93
How does secretin act on the liver?
It stimulates bile secretion.
94
How does secretin act on the stomach.
It inhibits gastric secretion and gastric emptying
95
What is the source of Cholecystokinin?
The duodenum.
96
What target tissue does cholecystokinin have?
Pancreas, gallbladder, and the Brain.
97
What effect does cholecystokinin have on the pancreas?
It stimulates the release of digestive enzymes.
98
What effect does cholecystokinin have on the gallbladder?
It stimulates the emptying of the bile.
99
What effect does cholecystokinin have on the Brain?
It helps regulate food intake by signaling satiety.
100
What are the factors that stimulate the release of cholecystokinin?
Presence of fatty acids nd partially digested proteins in duodenum.
101
Where is glucose-dependent insulin tropic peptide (GIP) originated from?
It is sourced from the duodenum’s mucosal cells.
102
What is the target tissue of GIP (Glucose-dependent insulinotropic peptide)?
The pancreas.
103
What is the action of Glucose-dependent-inuslinotropic peptide GIP?
It stimulates insulin secretion.
104
What influences the secretion of GIP (glucose-dependent inuslinotropic peptide)
The presence of glucose in the duodenum.
105
Where does Absorption of food take place?
It occurs mainly in through the villi of the small intestine.
106
What types of molecules can penetrate the stomach wall?
Small molecules such as water, simple sugars, salts, alcohol, and some drugs.
107
What is the wall of the villus composed of?
The wall of the villus is composed of a single layer of columnar epithelial cells.
108
Where do the absorbed nutrients go?
Absorbed nutrients pass through epithelial cells and into a capillary or lymph vessel by simple diffusion/ facilitated diffusion/ active transport.
109
What nutrients are absorbed by active transport?
Glucose and amino acids (coupled with active transport of Na)
110
Which nutrient is absorbed by facilitated diffusion?
Fructose.
111
Where do absorbed nutrients (glucose, amino acids,…etc)
Hepatic portal vein -> liver.
112
What happens to the absorbed food once it reaches the liver?
The blood is processed; nutrients and certain toxic substances are removed from circulation.
113
How are fatty acids and monoacylglycerols absorbed in the small intestines?
They enter epithelial lining -> reassembled to triacylglycerols in Smooth ER -> packaged into chylomicron.
114
What are chlyomicrons?
Other than triacylglycerols, they contain cholesterol and phospholipids. They’re covered by a protein coat.
115
What is the villus lymph vessel called?
Lacteal.
116
Where do chylomicrons diffused into?
Into the lacteal.
117
Where are the chylomicrons going to go after being diffused into the lacteal?
From the lymph vessel into the subclavian veins -> enter the blood stream directly.
118
What percentage of fat are absorbed into the blood circulation?
90 %.
119
What happens to short-chain fatty acids in the small intestines?
They are directly absorbed by the epithelial columnar cells.
120
What is the valve of the large intestine called?
Ileocecal valve.
121
Which diameter is bigger, that of the large intestine, or that of the small intestine?
The diameter of the large intestine is larger than the small intestines.
122
Where is the caecum located?
It is located at the junction between the small and large intestines.
123
What is the caecum usually referred to as?
The blind pouch.
124
Where is the vermiform appendix located?
It projects from the caecum. (Smaller blind sac than the caecum)
