Ch. 13 Animal Physiology

Question 1

Hydra - Digestion

Answer 1

Gastrovascular cavity, has only one opening.

Question 2

Cells of the gastrodermis (lining of the gastrovascular cavity) secrete digestive enzymes into the cavity for

Answer 2

extracellular digestion

Question 3

Earthworm - Digestion

Answer 3

From the mouth, food moves to the esophagus and then to the crop where it is stored. Posterior to the crop, the gizzard, which consists of thick, muscular walls, grinds up the food.

Question 4

Earthworm - absorption

Answer 4

Is enhanced by the presence of a large fold in the upper surface of the intestine -> typhlosole. which greatly increases the surface area.

Question 5

Grasshopper - Disgestion

Answer 5

a digestive tract consists of a long tube consisting of a crop and gizzard.

Question 6

Humans - Digestion

Answer 6

Digestion - breaking down large food molecules into smaller usable molecules.
Absorption - the diffusion of these smaller molecules in the body’s cells.

Question 7

Fats

Answer 7

Get broken down into glycerol and fatty acids.

Question 8

Starch

Answer 8

into monosaccharides

Question 9

Nucleic acids

Answer 9

into nucleotides

Question 10

Proteins

Answer 10

into amino acids

Question 11

Vitamins and minerals

Answer 11

They are small enough to be absorbed without being digested.

Question 12

Digestive tract

Answer 12

made of smooth (involuntary) muscle.

Question 13

Smooth (involuntary) muscle that pushes the food along the digestive tract by a process

Answer 13

Peristalsis

Question 14

Mouth

Answer 14

Tongue and teeth break down food mechanically.

Question 15

Salivary amylase

Answer 15

released by salivary glands begins the chemical breakdown of starch.

Question 16

Esophagus

Answer 16

After swallowing. food is directed into the esophagus, by the epiglottis, a flap of cartilage in the back of the pharynx (throat). No digestion occurs in the esophagus.

Question 17

Stomach

Answer 17

Churns food mechanically and secretes gastic juice.

Question 18

Gastric juice

Answer 18

A mixture of the enzyme pepsinogen and hydrochloric acid that begins the digestion of proteins.

Question 19

The acid environment (pH 2-3) activates ________ to become the active enzyme ______ and also kills germs.

Answer 19

Pepsinogen … pepsin

Question 20

The stomach of all mammals contains _______ to aid in the digestion of the protein in milk.

Answer 20

Rennin

Question 21

__________ at the top of the stomach keeps food in the stomach from backing up into the esophagus and burning it.

Answer 21

Cardiac sphincter

Question 22

__________ at the bottom of the stomach keeps the food in the stomach long enough to be digested.

Answer 22

Pyloric sphincter

Question 23

Digestion is completed in the _________

Answer 23

Duodenum

Question 24

Intestinal enzymes and pancreatic amylases hydrolyze starch and glycogen into _______.

Answer 24

Maltose

Question 25

_______ is produced in the liver and stored in the gallbladder

Answer 25

Bile

Question 26

Bile is released into the ______ as needed and acts as an _______ to break down fats, creating greater surface area for digestive enzymes.

Answer 26

Small intestine....... emulsifier

Question 27

________ such as trypsin and chymotrypsin, continue to break down proteins.

Answer 27

Peptidases

Question 28

Nucleic acids are hydrolyzed by ________

Answer 28

nucleases

Question 29

_______ break down fats

Answer 29

lipases

Question 30

The lower part of the small intestine is the site of _______.

Answer 30

Absorption

Question 31

Millions of fingerlike projections called _____ absorb all the nutrients that were previously released from digested food.

Answer 31

Villi

Question 32

Each villus contains _______, which absorb amino acids, vitamins and monosaccharides.

Answer 32

capillaries

Question 33

_______, a small vessel of the lymphatic system, which absorbs fatty acids and glycerol.

Answer 33

Lacteal

Question 34

Each epithelial cell of the villus has many microscopic cytoplasmic appendages called ________

Answer 34

Microvilli that greatly increase the rate of nutrient absorption by the villi.

Question 35

Gastrin - site of production and Effect

Answer 35

Stomach wall.... Stimulates sustained secretion of gastric juice.

Question 36

Secretin- site of production and Effect

Answer 36

Duodenum wall ..... Stimulates pancreas to release bicarbonate to neutralize acid in duodenum.

Question 37

Cholecystokinin (CCK)

Answer 37

Duodenum wall ..... Stimulates pancreas to release pancreatic enzymes and gall bladder to release bile into small intestine.