Question 1

Refer to the figure showing the digestive systems of an earthworm and a cockroach.  Identify the structure in each organism that is the primary site of nutrient absorption.

Accepted Answer

The answer of Refer to the figure showing the digestive...

Question 2

Refer to the figure showing the intestinal surface area of various organisms.  All of the structures labeled in the figure function to increase the surface area available for absorption.Which structure is correctly matched with its name?

Accepted Answer

Villi are finger-like projections that increase the surface area of the small intestine for absorption.

Answer: A
 The spiral valve is a structure found in the intestines of some fish that increases surface area for absorption by creating a spiral-shaped path for food.

Answer: B
 The typhlosole is a spiral-folded structure found in the intestine of some invertebrates, such as earthworms, that increases surface area for absorption.

Answer: E
 Lacteals are small lymphatic vessels in villi that play a role in fat absorption.

Answer: C
 The large intestine does not function to increase surface area for absorption. Instead, it is mainly responsible for absorbing water and electrolytes and forming feces.

Question 3

Which structure of the vertebrate gut is a membrane covering the abdominal organs and lubricating them so they easily slide against one another?

Accepted Answer

The peritoneum is a membrane that lines the abdominal cavity and covers the organs within it. It secretes a lubricating fluid that allows the organs to move and slide against each other without causing friction or damage.

Question 4

Which structure serves to increase surface area for nutrient absorption?

Accepted Answer

The spiral valve in a shark's intestine serves to increase surface area for nutrient absorption by increasing the length of the digestive tract. This allows for more time and space for nutrients to be absorbed into the bloodstream.

Question 5

In humans, which structure is closed off from food when food is swallowed?

Accepted Answer

The answer of In humans, which structure is closed off...

Question 6

Refer to the figure showing the digestive systems of an earthworm and a cockroach.  Which component of the digestive system is found in only one of the organisms in the figure?

Accepted Answer

Mandibles are present only in the cockroach and not in the earthworm.

Question 7

Nematocysts are an adaptation used by _______ to inject toxin into a victim.

Accepted Answer

Nematocysts are specialized cells found in the tentacles of jellyfish and are used to capture prey or defend against predators by injecting them with toxins.

Question 8

Refer to the figure showing a portion of the human stomach.  The part of the stomach shown in the figure does not show

Accepted Answer

The part of the stomach shown in the figure has gastric pits and gastric mucosa, which are responsible for secreting gastric juices and maintaining the proper pH for digestion. However, this section of the stomach does not have a significant surface area for absorption. Therefore, choice C is the correct answer. Choice A (pepsinogen-producing cells) and E (parietal cells producing H⁺ concentration gradients) are both present in the stomach and are not specifically related to the portion shown in the figure. Choice D (gastric mucosa) is already mentioned in the explanation, and so it is not the correct answer.

Question 9

Movement of food from the stomach into the esophagus is normally prevented by

Accepted Answer

The esophageal sphincter is a muscular valve that controls the movement of food from the esophagus into the stomach and prevents the contents of the stomach from refluxing back into the esophagus. This is achieved through the presence of a specialized ring of muscle that contracts tightly, preventing food from moving upward.

Question 10

Refer to the figure showing the intestinal surface area of various organisms.  In the figure of the human intestine, what is the structure labeled E, and what is its function?

Accepted Answer

The structure labeled E on the figure of the human intestine is a microvillus. Microvilli are small, finger-like projections that increase the surface area of the small intestine, allowing for more efficient absorption of nutrients.

Question 11

What is the key adaptation of most vertebrates that serves to increase absorptive area?

Accepted Answer

Increasing the length of the intestine is a key adaptation in vertebrates to increase the surface area for absorption of nutrients.

Question 12

The gut of a vertebrate is often described as an elongated tube consisting of four layers of different cell types.Which represents the correct order of those layers, from innermost (lumen-facing) to outermost?

Accepted Answer

The mucosa is the innermost layer facing the lumen, followed by the submucosa, circular muscle layer, and finally the longitudinal muscle layer. Options A, B, C, and E do not represent the correct order of the layers.

Question 13

The major function of the colon, or large intestine, is the

Accepted Answer

The large intestine, or colon, primarily functions to reabsorb water and ions from the remaining indigestible material that enters it from the small intestine. This helps to consolidate waste material and form feces for excretion. While some bacterial fermentation may occur in the colon, its primary function is not related to housing parasitic bacteria, secreting bile and enzymes, or digesting and absorbing nutrients from food.

Question 14

Refer to the figure showing the digestive systems of an earthworm and a cockroach.  Identify the structure in each organism used for food storage and some minimal, initial digestion.

Accepted Answer

The answer of Refer to the figure showing the digestive...

Question 15

Which teeth are most prominent in mammalian carnivores?

Accepted Answer

Canines are the most prominent teeth in mammalian carnivores, as they are used for killing and tearing apart prey. Incisors are used for grasping and biting off pieces of flesh, while premolars and molars are used for crushing and grinding food. Cheek teeth refer to premolars and molars collectively.

Question 16

Which structure is used as a storage chamber for food, but not for grinding food?

Accepted Answer

The crop is a specialized structure in the digestive system of some animals, such as birds and insects, that acts as a storage chamber for food. It is not involved in grinding or breaking down food like the gizzard or radula. The mandibles are used for biting and cutting food, while the esophagus is the muscular tube that connects the mouth to the stomach.

Question 17

Which example could be considered analogous to the vertebrate gut?

Accepted Answer

The answer of Which example could be considered analogous to...

Question 18

Refer to the figure showing the digestive systems of an earthworm and a cockroach.  Identify the structure in each organism used for grinding food.

Accepted Answer

The answer of Refer to the figure showing the digestive...

Question 19

Which layer of the vertebrate gut shows adaptations for increasing absorptive surface area?

Accepted Answer

The mucosa layer of the vertebrate gut shows adaptations for increasing absorptive surface area, such as the presence of villi and microvilli.

Question 20

Which statement about movement of food in the gut is true?

Accepted Answer

Smooth muscle of the gut contracts in response to being stretched, which helps move food along the digestive tract.

Answer: E
 The muscle in a sphincter is normally relaxed to allow food to pass through, and only contracts to prevent backflow or to control the rate of flow.

Therefore, both statements C and E are true.

Quiz 50: Nutrition, Digestion, and Absorption

Refer to the figure showing the digestive systems of an earthworm and a cockroach. Identify the structure in each organism that is the primary site of nutrient absorption.

Refer to the figure showing the intestinal surface area of various organisms. All of the structures labeled in the figure function to increase the surface area available for absorption.Which structure is correctly matched with its name?

Which structure of the vertebrate gut is a membrane covering the abdominal organs and lubricating them so they easily slide against one another?

Which structure serves to increase surface area for nutrient absorption?

In humans, which structure is closed off from food when food is swallowed?

Refer to the figure showing the digestive systems of an earthworm and a cockroach. Which component of the digestive system is found in only one of the organisms in the figure?

Nematocysts are an adaptation used by _______ to inject toxin into a victim.

Refer to the figure showing a portion of the human stomach. The part of the stomach shown in the figure does not show

Movement of food from the stomach into the esophagus is normally prevented by

Refer to the figure showing the intestinal surface area of various organisms. In the figure of the human intestine, what is the structure labeled E, and what is its function?

What is the key adaptation of most vertebrates that serves to increase absorptive area?

The gut of a vertebrate is often described as an elongated tube consisting of four layers of different cell types.Which represents the correct order of those layers, from innermost (lumen-facing) to outermost?

The major function of the colon, or large intestine, is the

Refer to the figure showing the digestive systems of an earthworm and a cockroach. Identify the structure in each organism used for food storage and some minimal, initial digestion.

Which teeth are most prominent in mammalian carnivores?

Which structure is used as a storage chamber for food, but not for grinding food?

Which example could be considered analogous to the vertebrate gut?

Refer to the figure showing the digestive systems of an earthworm and a cockroach. Identify the structure in each organism used for grinding food.

Which layer of the vertebrate gut shows adaptations for increasing absorptive surface area?

Which statement about movement of food in the gut is true?