When you eat an apple, it is first physically broken down into smaller fragments. What is the term for this process?
elimination
absorption
mastication
peristalsis
2.
Which of the following statements is true?
The majority of water is reabsorbed by the small intestine.
Elimination is a process that occurs via diffusion.
Absorption is the process that chemically breaks down food.
Nutrients diffuse across the epithelial cell lining of the small intestine to enter the bloodstream.
3.
Ruminants and pseudo-ruminants are both able to digest plant materials but have different mechanisms for doing so. Which of the following is a pseudo-ruminant?
cow
goat
crow
horse
4.
Which of the following statements about animal digestion is true?
Roughage is digested very quickly.
Birds eat large quantities at one time.
Birds have a four-chambered stomach.
In pseudo-ruminants, roughage is digested in the cecum.
5.
Chemical and mechanical digestion begins in the mouth, where food is prepared into a ______, which is then swallowed.
bolus
trachea
peristalsis
sphincter
6.
Which of the following statements about digestion is true?
Pepsin is converted to pepsinogen with the help of hydrochloric acid.
Starch digestion begins in the mouth.
Wave-like muscle movements called peristalsis move food from the stomach to the mouth.
Amino acids are absorbed through the intestinal lining of the ileum.
7.
Chyme is strongly acidic. What substance is secreted by the pancreas to neutralize chyme?
hydrochloric acid
bicarbonate
bile
amylase
8.
How do the liver's special cells assist in fat digestion?
produce bicarbonate
concentrate bile salts
produce bile
produce pepsin
9.
You eat food in order to obtain vital nutrients. How are these nutrients absorbed by your body?
Food is mechanically and chemically broken down into smaller molecules.
Alternating waves of muscular contraction facilitate movement of food.
Partially digested food flows into the small intestine and food regurgitation is prevented.
Nutrients diffuse across the intestines.
10.
Certain organs control the release of hormones that have vital roles in digestion. Which of the following controls hunger and satiety signals?
thymus
adrenal cortex
thyroid
hypothalamus
11.
One cup of which of the following is likely to have the most calories?
spaghetti with tomato sauce
deep-fried zucchini
mixed fruit
scrambled eggs
12.
Plant materials, such as fruits and vegetables, are difficult to digest because they are difficult to break down. How are humans able to obtain nutrients from fruits and vegetables?
Humans produce cellulase, which breaks down cellulose.
Intestinal flora have enzymes that break down some of the fiber.
Bile is released from the gallbladder to break down fiber.
In the stomach, pepsin is produced to break down plant material.
13.
Which statement is not an example of how fat is beneficial?
Fat helps absorb lipid-soluble vitamins.
Fat helps produce lipid-soluble hormones.
Fat has low energy density.
Fat makes you feel full faster.
14.
Certain molecules are required by but not produced by the body. Fat- and water-soluble _______ are organic molecules that cannot be produced by the body but are required for many enzymatic functions.
minerals
vitamins
amino acids
sugars
15.
What is the result of insufficient amounts of the mineral iodine in the body?
muscle weakness
poor immune function
mood disturbances
goiters
16.
Adenosine triphosphate, or ATP, is the source of energy for cells. ATP stores energy in _______ bonds.
carbohydrate
glycolysis
glycogen
phosphodiester
17.
Which of the following statements about glycogen is true?
When an individual is sedentary, glycogen is converted to glucose.
The liver releases glycogen when blood sugar drops.
ATP is produced by excess glycogen and glucose.
During glycolysis, glycogen is converted to pyruvic acid.
18.
What is produced from excess ATP and glucose?
glycogen
pyruvate
peptides
essential nutrients
19.
(credit: modification of work by Acham, Israel Okpunyi et al./Asian Food Science Journal)
The table shows the nutritional value of various meats and other food items.
Eating 100 g of which type of food would give the most proteins?
turkey
dried fish
cow milk
goat milk
20.
Different macromolecules have varying amounts of energy density. Which of the following is the least energy dense?
protein
fat
fiber
carbohydrates
21.
Which of the following does not play a role in masticating food?
teeth
pharynx
saliva
tongue
22.
Which of the following statements about the process of digestion is true?
Organisms absorb large molecules through digestive cells.
The last step of digestion is absorption.
Food is only mechanically broken down in the mouth.
Food is prepared into a bolus before it is swallowed.
23.
Which of the following enzymes is involved in carbohydrate digestion?
pancreatic amylase
elastase
trypsin
pepsin
24.
In protein digestion, what happens in the stomach?
Aminopeptidase and dipeptidase break peptides into amino acids.
Pepsin breaks proteins into peptides.
Trypsin, elastase, and chymotrypsin break proteins into peptides.
Carboxypeptidase breaks peptides into amino acids and peptides.
25.
Water reabsorption is an essential component of processing food. Where is the majority of water reabsorbed?
small intestine
rectum
colon
anus
26.
If you come down with the flu, you might experience emesis. What causes emesis?
stomach muscle contractions
neural signals that urge elimination
inadequate water reabsorption
excess water reabsorption
27.
Not all organs involved in processing food are involved in digestion. Which of the following organs is not involved in digestion?
mouth
anus
stomach
small intestine
28.
Which of the following statements about digestion of food in the large intestines is true?
Mechanical digestion occurs by bacteria.
Semi-solid waste is moved by wave-like muscle contractions.
Most nutrients are absorbed.
Peristaltic mixing occurs.
29.
Taking in food, or ____, is the first step of gaining nutrients from food.
digestion
ingestion
elimination
absorption
30.
What is the correct order of processes by which nutrients, energy, and waste from food are handled by organisms?
digestion → ingestion → absorption → elimination
ingestion → absorption → digestion → elimination
ingestion → digestion → absorption → elimination
ingestion → digestion → elimination → absorption
31.
Gastric control has three phases that assist in digesting food. Which phase is initiated by chyme?
intestinal
gastric
cephalic
digestive
32.
Which of the following occurs during the cephalic phase of gastric control?
Salivation is triggered.
Food is processed by gastric acids and enzymes.
Gastrin is produced.
Digestive secretions are released.
33.
Hormones play an important role in the digestion process of food. Which hormone controls the release of bile from the gallbladder?
pepsin
gastrin
amylase
cholecystokinin
34.
What is the role of gastrin in food digestion and absorption?
Gastrin stimulates release of stomach acid.
Gastrin stimulates production of bicarbonate.
Gastrin stimulates pancreatic juice production.
Gastrin stops the release of stomach acid.
35.
The gastric phase assists in processing ingested materials. When does the gastric phase begin?
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