Question 1

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

Accepted Answer

Long, closely packed gill rakers are typically an adaptation for suspension feeding, allowing the fish to filter small particles or plankton from the water.

Question 2

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?

Accepted Answer

Some animals, such as certain species of sponges, lack both mouths and gastrointestinal tracts, obtaining nutrients through other means like filter feeding.

Question 3

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?

Accepted Answer

The study found that spiders exhibited a compensatory feeding behavior, preferring the diet that balanced their previous intake, thus spiders on a protein-rich diet preferred lipid-rich flies and vice versa.

Question 4

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

Accepted Answer

The radular teeth of snails are sometimes hardened by the addition of iron and silica, which help in strengthening the teeth for feeding.

Question 5

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.

Accepted Answer

In a three-level food chain, there are fewer energy transfers, meaning less energy is lost at each trophic level. Therefore, dinosaurs at the top would receive more energy compared to longer food chains.

Question 6

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

Accepted Answer

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

Question 7

The feeding modes that is most associated with a ruminant is

Accepted Answer

Ruminants have a specialized stomach with multiple chambers that host symbiotic microbes to help break down cellulose from plant material.

Question 8

The sulfur-oxidizing bacteria of hydrothermal vent communities are

Accepted Answer

Sulfur-oxidizing bacteria in hydrothermal vent communities are aerobic and chemoautotrophic, meaning they use oxygen to oxidize sulfur compounds to obtain energy and fix carbon dioxide into organic matter.

Question 9

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

Accepted Answer

Bacteria are the most abundant component of the gut microbiome in humans.

Question 10

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

Accepted Answer

Some animals have symbiotic relationships with microorganisms that produce cellulase, an enzyme that breaks down cellulose, allowing the animals to digest cellulose indirectly.

Question 11

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

Accepted Answer

Microbes in the rumen are primarily involved in breaking down cellulose, synthesizing B vitamins, and producing essential amino acids. Water balance is not a function of rumen microbes.

Question 12

Ruminants obtain energy from cellulose by

Accepted Answer

Ruminants obtain energy from cellulose primarily by absorbing short-chain fatty acids produced by microbial fermentation in the rumen and by digesting the microbes themselves, which break down the cellulose.

Question 13

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

Accepted Answer

The answer of Which animal would be most likely to...

Question 14

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 _______.

Accepted Answer

The rumen of a cow functions like a continuous-flow reactor with mixing, allowing for constant input and mixing of contents. The intestine functions like a continuous-flow reactor without mixing, where contents move through without significant mixing.

Question 15

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

Accepted Answer

Hindgut fermenters absorb nutrients in the small intestine, but microbial fermentation occurs in the hindgut, after the small intestine. Coprophagy allows them to re-ingest feces to absorb nutrients produced by microbes.

Question 16

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

Accepted Answer

The abomasum is the stomach chamber in ruminants that secretes acid and digestive enzymes, functioning similarly to the monogastric stomach.

Question 17

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

Accepted Answer

The answer of Refer to the figure shown.
 What is...

Question 18

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

Accepted Answer

The answer of Refer to the figure shown.
 What is...

Question 19

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

Accepted Answer

The answer of Refer to the figure shown.
 According to...

Question 20

Which statement best describes blue whale feeding?

Accepted Answer

Blue whales feed by taking in a large volume of water containing krill and then forcing the water out through their baleen plates, trapping the krill inside their mouths to be swallowed.

Quiz 6: Nutrition, Feeding, and Digestion