Deck 6: Nutrition, Feeding, and Digestion

Question 1

Among Africans, the Masai are unusual in that

A) adults are strict carnivores.
B) adults and children both produce lactase.
C) only adults produce lactase.
D) adults do not produce lactase but they can drink milk without gut distress.

Answer 1

B

Question 2

Which factor is not required for a food to have nutritional value.

A) Food must be ingestible.
B) Food must be digestible.
C) Food must have an essential component to it.
D) Food must be absorbable.

Answer 2

C

Question 3

Why do animals need to eat?

A) Individual molecules deteriorate.
B) Chemical-bond energy used in metabolism can be reused.
C) Animals are physiologically static systems.
D) Cells become damaged and need to be replaced.

Answer 3

D

Question 4

Which body component has the greatest mass in a normal, slender adult human?

A) Proteins
B) Lipids
C) Nucleic acid
D) Carbohydrates

Question 5

Suppose a normal, slender adult gains 10 kg of fat. Which body component would weigh the most?

A) Proteins
B) Lipids
C) Nucleic acid
D) Body water

Question 6

Which substances do not contain nitrogen?

A) Essential and nonessential amino acids
B) Carbohydrates and lipids
C) Lipids and proteins
D) Carbohydrates and polypeptides

Question 7

Herbivorous animals obtain their nitrogen primarily from

A) nitrogen gas.
B) nitrates in drinking water.
C) ammonium in drinking water.
D) proteins in plants they eat.

Question 8

In terms of essential nutritional requirements for particular molecules, the most exacting requirements are for _______ and the least exacting are for _______.

A) proteins; carbohydrates
B) proteins; lipids
C) carbohydrates; lipids
D) carbohydrates; proteins

Question 9

A nonessential amino acid is an amino acid that

A) is stored for future use in building proteins.
B) can be synthesized by the animal.
C) is deaminated and used in other biochemical pathways.
D) can be used to synthesize essential amino acids.

Question 10

In children, there are nine essential amino acids but in adults there are only eight. What accounts for this?

A) Adults can synthesize enough of one amino acid that children cannot.
B) Children store one essential amino acid that they later use as adults.
C) Adults lose the ability to synthesize one amino acid that children can synthesize.
D) Adults have an amino acid transporter that children lack.

Question 11

Organic chemists and biochemists often classify molecules based on similarities in their chemical composition. For which compound would developing a generalizable "formula" for chemical composition be most difficult?

A) Proteins
B) Carbohydrates
C) Lipids
D) Vitamins

Question 12

Mineral deficiencies are a major problem in some impoverished regions of the world. Ultimately, mineral deficiencies result from

A) soils with insufficient mineral availability.
B) diets low in lipids.
C) lactose intolerance.
D) diets with insufficient protein.

Question 13

One of the minerals that is particularly important for lactating females and their offspring is

A) selenium.
B) calcium.
C) zinc.
D) riboflavin.

Question 14

Which vitamin is most closely integrated with calcium metabolism?

A) Vitamin B₁₂
B) Vitamin D
C) Vitamin E
D) Vitamin K

Question 15

A newborn is having problems with excessive bleeding following a very minor injury. It is therefore suspected that vitamin _______ was inadequate following birth.

A) B₁₂
B) D
C) E
D) K

Question 16

You are browsing at a nutritional supplement store and a representative is trying to sell you their brand of bulk amino acid supplements because this particular brand contains only essential amino acids, which are clearly needed by the body. Would the additional expense of this brand be worth it?

A) No - The body will naturally obtain essential amino acids.
B) No - Although we require the essential amino acids, the excess ingested would be quickly broken down for other purposes and wasted.
C) Yes - You should consume as many essential amino acids in your diet as possible.
D) Yes - We rarely obtain all the essential amino acids we require in our diet.

Question 17

Lipids are important for all of the following except

A) reducing the permeability of the integument to water.
B) storing water.
C) forming cellular membranes.
D) serving as hormones (for example, steroid lipids).

Question 18

The carbohydrates _______ are likely to be more important in insects than in mammals.

A) trehalose and glycogen
B) trehalose and chitin
C) glucose and glycogen
D) trehalose and fructose

Question 19

Suspension feeding is more common in aquatic environments than in terrestrial environments because

A) terrestrial vertebrates are too large to suspension feed.
B) terrestrial animals are too selective in their feeding to be suspension feeders.
C) terrestrial animals typically feed lower on the food chain than aquatic animals do.
D) small suspended food items are abundant in aquatic systems but not in terrestrial systems.

Question 20

Which animal is not a suspension feeder?

A) Blue whale
B) Whale shark
C) Snail
D) Crabeater seal

Question 21

Suppose you discover the fossilized gill arches from a previously unknown species of fish. The gill arches have long, closely packed gill rakers. This fish most likely obtained its energy from

A) eating aquatic plants.
B) eating large molluscs.
C) autotrophy.
D) suspension feeding.

Question 22

You discover a fossil of an organism that came from a deep marine environment. The fossil has no mouth or gastrointestinal tract, and your colleague thinks that it cannot be that of an animal. Is your colleague correct?

A) Yes, because all animals have mouths.
B) Yes, because all animals have gastrointestinal tracts.
C) Yes, because all animals have both mouths and gastrointestinal tracts.
D) No, because some animals lack both mouths and gastrointestinal tracts.

Question 23

In the study by Mayntz et al., wolf spiders were fed either a protein-rich or lipid-rich diet of fruit flies (Drosophila) and then tested for their preference by being presented with each diet in sequence. Which statement about the results of the study is true?

A) All spiders preferred protein because protein is both uniquely important and uniquely tenuous in animal nutrition (i.e., it is "foremost").
B) All spiders preferred lipid because it has the most energy per gram.
C) Spiders on the protein-rich diet ate flies rich in protein and spiders on the lipid-rich diet ate flies rich in lipid.
D) Spiders on the protein-rich diet ate flies rich in lipid and spiders on the lipid-rich diet ate flies rich in protein.

Question 24

The radular teeth of snails are sometimes hardened by the addition of

A) calcium and iodine.
B) iron and silica.
C) iron and folate.
D) copper and vitamin K.

Question 25

Suppose that large nonavian dinosaurs still roamed the earth. If the lowest level of the food chains started with the same amount of energy, dinosaurs at the top of the food chain would receive the most amount of energy from a _______ food chain.

A) three-level
B) four-level
C) five-level
D) six-level

Question 26

The microbes that live in the guts of animals are collectively known as the gut

A) microhome.
B) microbiome.
C) lumen.
D) culture.

Question 27

The feeding modes that is most associated with a ruminant is

A) attack of individual prey items.
B) suspension feeding.
C) association with symbiotic microbes.
D) coprophagy

Question 28

The sulfur-oxidizing bacteria of hydrothermal vent communities are

A) anaerobic and heterotrophic.
B) aerobic and heterotrophic.
C) anaerobic and chemoautotrophic.
D) aerobic and chemoautotrophic.

Question 29

The most abundant component of the gut microbiome in humans is(are)

A) archaea.
B) bacteria.
C) viruses.
D) prions.

Question 30

Cellulose is one of the most abundant organic molecules in the biosphere, but most animals lack the enzymes needed to break it down. Nevertheless, some animals have and can digest a diet high in cellulose because

A) cellulose provides essential fatty acids.
B) their microbial symbionts break it down, allowing them to obtain energy from cellulose indirectly.
C) cellulose is a required nutrient for microbial symbionts.
D) the only food supply available to them contains large amounts of cellulose.

Question 31

Which process is not a useful function of microbes in the rumen?

A) Breakdown of cellulose
B) Synthesis of B vitamins
C) Synthesis of essential amino acids
D) Water balance

Question 32

Ruminants obtain energy from cellulose by

A) absorbing short-chain fatty acids produced by microbes and digesting microbes that break down the cellulose.
B) absorbing proteins produced by microbes and digesting microbes that break down the cellulose.
C) absorbing both short-chain fatty acids and nonessential amino acids produced by microbes.
D) absorbing both essential and nonessential amino acids produced by microbes.

Question 33

Which animal would be most likely to survive on a diet high in cellulose and low in nitrogen?

A) Sheep
B) Horse
C) Rabbit
D) Koala

Question 34

The reactor model that is most analogous to the rumen of a cow is the _______; the model that is most analogous to the intestine of a cow is the _______.

A) continuous-flow reactor with mixing; continuous-flow reactor without mixing
B) continuous-flow reactor without mixing; continuous-flow reactor with mixing
C) batch reactor; continuous-flow reactor with mixing
D) continuous-flow reactor without mixing; batch reactor

Question 35

Nutritionally, the consumption of feces (coprophagy) makes more sense for hindgut fermenters than foregut fermenters. Why?

A) Nutrients produced by microbes in the hindgut are not absorbed; therefore, coprophagy enables hindgut fermenters to absorb nutrients produced by microbes.
B) Microbial symbionts are not activated to produce nutrients unless they have passed through the digestive system at least twice.
C) Microbial symbionts are rarely excreted; therefore, coprophagy enables hindgut fermenters to increase the population of beneficial microbes.
D) The microenvironment in the hindgut is more favorable to microbes compared to the foregut.

Question 36

In a ruminant animal, the stomach chamber that secretes acid and digestive enzymes is called the

A) rumen.
B) reticulum.
C) abomasum.
D) cecum.

Question 37

Refer to the figure shown.
What is the best title for this panel?

A) Death rate is altered by diet
B) Diet affects activity level
C) Balancing protein and lipid intake
D) Food selection affects metabolic rate

Question 38

Refer to the figure shown.
What is the best label for the y axis?

A) Food amount eaten (mg)
B) Metabolic rate (J/mg/h)
C) Activity (Watts/h)
D) Percent protein or lipid

Question 39

Refer to the figure shown.
According to the graph, spiders that fed most on protein-rich flies during the 24-hour period before testing

A) were more active compared to those fed lipid-rich flies.
B) preferred lipid-rich flies over the next 72 h.
C) had a body composition higher in protein compared to fat.
D) had the highest metabolic rate.

Question 40

Which statement best describes blue whale feeding?

A) A blue whale sucks in water containing krill across the baleen arrays. The krill caught in the baleen is then swallowed.
B) A blue whale takes in a huge volume of water containing krill and forces the water out laterally through baleen arrays. The krill are left behind in the mouth and swallowed.
C) A blue whale takes in a large volume of water containing krill, which is swallowed.
D) A blue whale takes in small amounts of water containing krill and pushes it across the baleen plates. When enough krill collects in the baleen, it is then all swallowed in one gulp.

Question 41

The posterior "pyloric" stomach chamber of a crustacean often has a lining of bristlelike setae. Collectively, these setae share a functional similarity with the omasum of ruminants, in that both

A) prevent larger food particles from passing down the digestive tract.
B) participate in the mechanical grinding of food.
C) participate in the storing of food.
D) are the primary site of nutrient absorption.

Question 42

Many bats and rodents feed on insects, but humans and rabbits generally do not. These dietary habits suggest that

A) humans and rabbits are strict herbivores.
B) many bats and rodents produce cellulase and chitinase enzymes, but humans and rabbits do not.
C) many bats and rodents produce cellulase enzymes, but humans and rabbits do not.
D) many bats and rodents produce chitinase enzymes, but humans and rabbits do not.

Question 43

The entry of molecules into the living tissues of an animal from outside the living tissues of an animal is called

A) targeted entry.
B) absorption.
C) intracellular digestion.
D) extracellular digestion.

Question 44

In vertebrates, the principal site of digestion of carbohydrates and lipids is the

A) headgut.
B) foregut.
C) midgut.
D) hindgut.

Question 45

Which substance(s) is(are) secreted in one part of the digestive tract and then reabsorbed downstream?

A) Bile salts and sodium
B) Proenzymes
C) Exopeptidases
D) Zymogens

Question 46

A major difference between vertebrate and insect digestive systems is that

A) only vertebrates have a foregut.
B) gut motility is a characteristic of vertebrates only.
C) the hindgut affects urine composition in insects but not in vertebrates.
D) insects lack digestive enzymes and rely solely on endosymbionts.

Question 47

In crustaceans, the hepatopancreas performs functions very similar to those of the _______ in vertebrates.

A) liver
B) pancreas
C) liver and pancreas
D) stomach

Question 48

In which animal does intracellular digestion play a major role?

A) Fish
B) Molluscs
C) Insects
D) Crustaceans

Question 49

Which substance is associated with extracellular digestion?

A) Intraluminal enzymes
B) Membrane-associated enzymes
C) Intracellular enzymes
D) Intraluminal enzymes and membrane-associated enzymes

Question 50

Which substance is a disaccharidase?

A) Amylase
B) Lactase
C) Sucrose
D) Fructase

Question 51

_______ contain the greatest diversity of chemical bonds that must be broken down during digestion.

A) Structural carbohydrates
B) Nonstructural carbohydrates
C) Proteins
D) Lipids

Question 52

The inactive forms of digestive enzymes are called

A) endopeptidases.
B) inactivases.
C) zymogens.
D) bile salts.

Question 53

Bile salts are important for the effective functioning of

A) amylase.
B) endopeptidases.
C) exopeptidases.
D) lipases.

Question 54

Two transporters are needed for secondary active transport of glucose into a midgut epithelial cell. One transporter is needed to pump _______, and the other is needed to _______.

A) Na⁺; cotransport glucose
B) glucose; pump water
C) Ca²⁺; cotransport glucose
D) glucose; pump galactose

Question 55

In humans and many other vertebrates, the midgut contains minute fingerlike projections called _______ that increase the surface area of the gut epithelium.

A) villi
B) goblet cells
C) crypts
D) enterocytes

Question 56

Three polypeptide hormones secreted in the upper midgut are gastric inhibitory polypeptide,

A) gastrin, and secretin.
B) cholecystokinin, and secretin.
C) gastrin, and cholecystokinin.
D) secretin, and acetylcholine.

Question 57

Which substance has stimulatory effects on acid-secreting cells, pepsinogen-secreting cells, and muscle motility in the stomach?

A) Secretin
B) Cholecystokinin
C) Gastrin
D) Gastric inhibitory polypeptide

Question 58

Refer to the figure shown.
In which area(s) is sodium transport involved?

A) I
B) I and II
C) II and III
D) II and IV

Question 59

Refer to the figure shown.
In which area(s) is facilitated diffusion of fructose occurring?

A) I
B) I and II
C) I and III
D) II and III

Question 60

Refer to the figure shown.
In which area(s) is secondary active transport occurring?

A) I
B) II
C) I and III
D) IV

Question 61

Refer to the figure shown.
What process is being shown by the figure?

A) Fatty acid absorption
B) Fatty acid metabolism
C) Bile synthesis
D) Glycerol cycling

Question 62

Refer to the figure shown.
Which label most accurately points to lipoproteins?

A) I
B) II
C) III
D) IV

Question 63

Which hormone increases muscle motility of the stomach?

A) Gastrin
B) Secretin
C) Leptin
D) Cholecystokinin

Question 64

One of the weird side effects of a drug you are taking is reduced gut segmentation. How might this manifest itself as a symptom?

A) Food you eat takes longer to go through your intestinal tract.
B) Food has trouble exiting the stomach
C) Food exiting your intestinal tract is less fully broken down.
D) You have trouble swallowing food.

Question 65

Following a large meal, which hormone(s) is downregulated?

A) Gastrin
B) Ghrelin
C) Secretin
D) Cholecystokinin

Question 66

Many "megachiropteran" bats feed on fruit, and many "microchiropteran" bats feed on insects. If you capture a number of bats from each of these groups and feed them all fruit because you are unable to find insects to feed them, what is most likely to occur (provided the other aspects of their captivity are low in stress)?

A) Both groups will do equally well if there are a wide variety of fruits available.
B) The microchirpteran group is likely to lag briefly because of a general lack of gut enzymes and transporters for fruit sugars but will adapt to fruits within days.
C) The microchirpteran group is likely to do very poorly because of a general lack of gut enzymes and transporters for fruit sugars.
D) The megachirpteran group is likely to do very poorly because of a general lack of gut enzymes and transporters for fruit sugars.

Question 67

Many "megachiropteran" bats feed on fruit, and many "microchiropteran" bats feed on insects. Compared to "megachiropteran" bats, "microchiropteran" bats probably secrete _______ amylase and _______ pancreatic peptidase. They also probably have a _______ density of sugar transporters and a _______ density of amino acid transporters.

A) less; more; lower; lower
B) less; more; lower; higher
C) more; less; lower; higher
D) more; less; higher; lower

Question 68

Why is phenotypic plasticity important in digestion and absorption by vertebrates?

Question 69

Omega-3 and omega-6 fatty acids are essential fatty acids. Can eating saturated fatty acids supply these essential nutritional needs? Explain.

Question 70

Explain how the chemical structure of the retinol (vitamin A) molecule makes it suitable for inclusion in visual pigments of animals?

Question 71

Urea is highly soluble in water and readily diffuses across cells, but uric acid is relatively insoluble in water and does not readily diffuse across cell membranes. If ruminants excreted their nitrogenous wastes as uric acid, how might that affect the benefits that symbiotic microbes provide to them?

Question 72

If the Na⁺-K⁺-ATPase in the basolateral membrane were blocked, would you predict a larger effect on glucose transport or fructose transport? Why?

Question 73

Some people have trouble swallowing pills. What might account for this?

Question 74

In some ways, short-chain fatty acids share similarities with monosaccharides and amino acids. In other ways, they resemble long-chain fatty acids. What characteristic of short-chain fatty acids accounts for these resemblances?

Question 75

What response to the ingestion of food is shared by Burmese pythons and molluscs such as oysters, muscles, and clams?

Question 76

Why can the nutritional value of a single food item vary across animals and across time?

Question 77

Running is an energetically costly activity. If mice that normally run 4 km a day are forced to run 10 km a day, what might happen to their digestive tract?