Digestive System

Question 1

Anus :)

Answer 1

the opening through which solid waste leaves the body; posterior opening, protected by anal sphincter

Question 2

Bile

Answer 2

salty green liquid produced by the liver; stored in the gallbladder until a hormone signals its release; emulsifies fats

Question 3

Capillary

Answer 3

located in intestines, pick up nutrients; smallest type of blood vessel

Question 4

Cardiac sphincter

Answer 4

muscle constriction at the base of the esophagus (cardiac = close to the heart), must relax and open before food materials can enter esophagus; prevents contents of stomach from moving back up

Question 5

Chemical digestion

Answer 5

involves enzymes which break down chemical bonds in food, allowing them to be digested easily

Question 6

Digestive enzyme

Answer 6

hydrolytic enzymes that chemically break food molecules into monomers; found in saliva, gastric juice, pancreatic, and intestinal juice

Question 7

Digestive tract

Answer 7

tube which conducts food through the body from mouth to anus; has accessory organs attached to it

Question 8

Duodenum

Answer 8

first part of the small intestine (about 6 in); food materials are released from stomach via pyloric sphincter; where majority of digestive activity takes place

Question 9

Emulsification

Answer 9

the process of mechanically breaking (physically digesting) fat clusters into smaller pieces through the use of bile

Question 10

Epiglottis

Answer 10

ventral flap of tissue that opens the top of trachea for breathing and closes it during swallowing, preventing individuals from choking

Question 11

Esophagus

Answer 11

entry point to the stomach; lined with circular and longitudinal muscles which conduct peristalsis

Question 12

Gallbladder

Answer 12

where bile is stored until its release; attached to underside of liver

Question 13

Gastric juice (stomach fluids)

Answer 13

mixture of fluids secreted by stomach (fruit punch but stomach ver.)

Question 14

Hydrochloric acid (HCl)

Answer 14

pH 1.5-2.5; combines with pepsinogen to make pepsin

Question 15

Insulin

Answer 15

secreted by the pancreas; lowers blood sugar levels by increasing cell’s ability to use it; promotes storage in the form of glycogen

Question 16

Intestinal juice

Answer 16

secreted by small intestine; contains additional enzymes such as disaccharidases and peptidases

Question 17

Lacteals

Answer 17

absorptive end of lymphatic system + where reconstructed fats go (aka lymph capillary), transport products of fat digestion away from intestine

Question 18

Large intestine (colon)

Answer 18

where remains of food and indigestible materials like cellulose pass into

Question 19

Lipase

Answer 19

digests lipids by removing the fatty acid from the glycerol molecule

Question 20

Liver

Answer 20

body’s largest internal organ, posterior to the diaphragm; many functions aside from digestion (mainly produces bile to emulsify fats)

Question 21

Maltase

Answer 21

completes digestion of carbohydrates into monosaccharides that can be absorbed (ie. breaks down maltose into a single sugar)

Question 22

Nuclease

Answer 22

enzyme which digests nucleic acids (DNA + RNA) into nucleotides ACTG and U; is a component of both pancreatic and intestinal juice

Question 23

Pancreas

Answer 23

produces pancreatic juice and specializes as an endocrine gland: produces and secretes insulin and glucagon

Question 24

Amylase

Answer 24

enzyme which dissolves starch into maltose, is produced by the salivary glands and pancreas (also in salivary glands)

Question 25

Pancreatic juice

Answer 25

made of six components: four enzymes (amylase, lipase, trypsin, and nuclease), a buffer (sodium bicarbonate), and water; each enzyme contributes to digestion of a specific polymer

Question 26

Pepsin

Answer 26

breaks down large proteins into peptides (5-10 AA), made of HCl reacting with pepsinogen

Question 27

Pepsinogen

Answer 27

precursor of pepsin secreted by the stomach wall; must react with HCl to become pepsin, HCl removes amino acids

Question 28

Peptidase

Answer 28

breaks polypeptide bonds in the duodenum (from 2-3 AA to 1 AA)

Question 29

Peristalsis

Answer 29

series of wave-like muscle contractions that move food through the digestive tract; begins in esophagus

Question 30

Pharynx

Answer 30

region in the back of the mouth, serves as a common passageway for food and air

Question 31

Physical digestion

Answer 31

also known as mechanical digestion; physical change: breaks food up into smaller pieces

Question 32

Protease

Answer 32

enzyme which digests proteins, such as pepsin

Question 33

Pyloric sphincter

Answer 33

similar to cardiac sphincter; located at the posterior end of the stomach and controls passage of acid chyme into the duodenum

Question 34

Rectum

Answer 34

temporarily stores feces until defecation; last portion of the large intestine lined with nerves- when it is full, sends signal through the nervous system to trigger the "dumping reflex"

Question 35

Salivary amylase (pytalin)

Answer 35

breaks down starch into sugar (maltose)

Question 36

Salivary gland

Answer 36

produces saliva for the mouth

Question 37

Salivary juice

Answer 37

lubricates food for easier swallowing- sticks food together

Question 38

Small intestine

Answer 38

produces and secretes intestinal juice; specialized for transport, digestion and absorption

Question 39

Sodium bicarbonate

Answer 39

buffer in pancreatic juice; dissociates to release bicarbonate ions and neutralizes pH from 3 to 8.5 so that pepin stops working and ensures there are no holes in small intestine!

Question 40

Stomach

Answer 40

J-shaped organ which stores and disinfects food through stomach acid; source of both physical and chemical digestion

Question 41

Swallowing

Answer 41

process by which food moves down the esophagus and into the stomach

Question 42

Trypsin

Answer 42

originally produced as trypsinogen; breaks down large peptides into smaller peptides (2-3 AA)

Question 43

Villus

Answer 43

finger-like projections in small intestine specialized for absorption