Digestive System

Question 1

Sections of alimentary canal (5)

Answer 1

Oral Cavity
Esophagus
Stomach
Small Intestine
Large Intestine

Question 2

Accessory organs of digestive system

Answer 2

• Salivary glands
• Pancreas
• Liver
• Teeth & tongue (not organs)
• Gallbladder

Question 3

Salivary glands

Answer 3

Secrete saliva. Saliva is made of mucus, serous fluids (salivary amylase), and lysozyme & antibodies.

Question 4

Pancreas

Answer 4

Exocrine function: secretes digestive enzymes

Question 5

Mechanical digestion

Answer 5

Physical changes that occur from chewing, stomach churning, and segmentation by small intestine

Question 6

Four major types of teeth

Answer 6

Incisors (2/quadrant)
Canine (1/quadrant)
Premolars/bicuspids (2/quadrant)
Molars (3/quadrant)

Question 7

Chemical digestion

Answer 7

Hydrolisis reactions where enzymes break large food molecules down to their building blocks

Question 8

Transverse section of alimentary canal, layers

Answer 8

Serosa
Muscularis externa 
- Longitudinal fibers
- Circular fibers
Submucosa
Mucosa

Question 9

Esophagus

Answer 9

Conducts food from pharynx to stomach, ~10 inches

Question 10

Gastric gland

Answer 10

• Situated in gastric pits

- Secretes gastric juice

Question 11

Parietal cells

Answer 11

Excrete HCl (hydrochloric acid)

Question 12

Chief cells

Answer 12

Excrete enzyme pepsinogen, which changes to its active form pepsin with the addition of HCl

Question 13

Small Intestine

Answer 13

• Duodenum (4%) (mostly nutrient absorption)
• Jejunum (40%)
• Ileum (56%) (water absorption and mucous production, lots of goblet cells)

Question 14

Segments of large intestine (7)

Answer 14

1. Cecum
2. Ascending colon
3. Transverse colon
4. Descending colon
5. Sigmoid colon
6. Rectum
7. Anus

Question 15

Primary functions of large intestine

Answer 15

• Dry out indigestible food residue by absorbing water
• Eliminate these residues from body as feces
• no villi

Question 16

Gastrin

Answer 16

• Produced by enteroendocrine cells
• Stimulates release of gastric juice
• Stimulates stomach emptying

Question 17

Secretin

Answer 17

• Causes the liver to increase bile output (bile is necessary for fat absorption)

Question 18

Cholecystokinin (CCK)

Answer 18

• Causes the gallbladder to release stored bile

Question 19

Brush border enzymes

Answer 19

• Break down double sugars into simple sugars

- Complete some protein digestion

Question 20

Pepsin

Answer 20

• Active protein-digesting enzyme

- In the protease category

Question 21

Rennin

Answer 21

• Digests milk protein in infants

Question 22

Pancreatic amylase

Answer 22

• Digestion of starch

Question 23

Lipase

Answer 23

• Fat digestion

Question 24

Nuclease

Answer 24

• Nucleic acid digestion

Question 25

Trypsin, chymotrypsin, carboxpeptidase

Answer 25

- Protein digestion

Question 26

Carbohydrates

Answer 26

- Derived mainly from plants, also lactose in milk and glycogens in meats - End products are galactose, glucose, fructose - Contain cellulose which act as fiber and aids digestion

Question 27

Lipids/fats

Answer 27

- Saturated fats from animal products - Unsaturated fats from nuts, seeds, veggie oils - End products are fatty acids and glycerol - Cholesterol from egg yolk, meats, milk products - Fats build myelin sheaths and cell membranes

Question 28

Proteins

Answer 28

- End product: amino acids - Complete proteins contain all essential amino acids - Most from animal, some incomplete from legumes and beans - Uses are functional and structural proteins (or ATP if other materials are lacking or there is excess)

Question 29

Vitamins

Answer 29

- Found in all major food groups | - Most are coenzymes (act with an enzyme to accomplish a particular type of catalysis)

Question 30

Anabolism

Answer 30

- Larger molecules or structures are built from smaller ones

Question 31

Catabolism

Answer 31

- Substances are broken down to simpler substances

Question 32

Liver (digestion)

Answer 32

- Detoxifies drugs and alcohol - Degrades hormones - Produces cholesterol, blood proteins - Manufactures bile

Question 33

Glycogenesis (liver)

Answer 33

- Glycogen formation | - Glucose molecules are converted to glycogen, glycogen is stored in the liver

Question 34

Glycogenolysis (liver)

Answer 34

- Glucose splitting | - Glucose is released from the liver after conversion from glycogen

Question 35

Gluconeogenesis (liver)

Answer 35

- Formation of new sugar | - Glucose is produced from fats and proteins

Question 36

Carbohydrates in cell metabolism

Answer 36

- ATP - Excess stored as glycogen or fat - Can be broken down by liver for ATP formation or broken down to glucose and released in blood

Question 37

Fats in cell metabolism

Answer 37

- ATP synthesis by liver, after being broken down to acetic acid - Build myelin sheaths and cell membranes

Question 38

Proteins in cell metabolism

Answer 38

- Broken down to amino acids - Amine groups are removed from proteins as ammonia - Liver converts harmful ammonia to urea

Question 39

Factors that influence metabolic rate

Answer 39

- Surface area: smaller body has higher basic metabolic rate (BMR) - Gender: males have higher BMR - Age: children and adolescents have higher BMR - Amount of thyroxin: more means higher metabolic rate

Question 40

Swallowing

Answer 40

- Buccal phase: voluntary, forces bolos (chewed up food) into pharynx - Pharyngeal-esophageal phase: involuntary, transports down pharynx and esophagus, everything moves in unison, longitudinal then circular muscles contract

Question 41

Pyloric sphincter

Answer 41

- Stomach enters small intestine

Question 42

Cellular respiration

Answer 42

- Oxygen-using events take place within the cell to create ATP from ADP - Glycolysis: energizes a glucose molecule - Krebs cycle: produces all carbon dioxide and water from cell respiration

Question 43

Cholesterol

Answer 43

- Not used for ATP - Structural basis for steroid hormones, building block for plasma membranes - Most is not eaten, but produced in the liver