Question 1

Animals with a complex body plan can maintain homeostasis in a changing environment by using all of the following except

Accepted Answer

Animals with a gastrovascular cavity that opens directly to the external environment do not have a complete digestive system, which can lead to difficulty maintaining homeostasis in a changing environment. All of the other options listed (sensory organs, internal digestive organs, external skeleton, and filtration system) are important for maintaining homeostasis in complex animals.

Question 2

Evolutionary adaptations that help diverse animals directly exchange matter between cells and the environment include

Accepted Answer

An external respiratory surface (such as gills, lungs, or skin) allows for direct exchange of gases between the environment and cells. A small body size increases surface area to volume ratio and allows for more efficient exchange. A two-cell-layered body (such as in cnidarians) allows for direct diffusion of gases and nutrients without the need for a circulatory system.

Question 3

As body size increases in animals

Accepted Answer

As body size increases, the volume increases at a faster rate than the surface area, resulting in a decrease in the surface-to-volume ratio. This has important implications for heat exchange, nutrient absorption, and waste removal, among other things.

Question 4

If thermoregulation is considered to be a secondary function of the large ears of jackrabbits,then the primary function of the ears is

Accepted Answer

The large size and flexible positioning of the external ears of jackrabbits allow them to hear sounds from various directions, which helps them detect and avoid predators. This is considered to be the primary function of their ears, with thermoregulation being a secondary function.

Question 5

Most of the exchange surfaces of multicellular animals are lined with

Accepted Answer

Epithelial tissue is specialized for exchange of materials between different environments, so it is the tissue type that lines exchange surfaces in multicellular animals. Connective tissue, smooth muscle cells, neural tissue, and adipose tissue are not specialized for exchange surfaces.

Question 6

When the temperature of the outside air exceeds their internal body temperature,jackrabbits living in hot,arid lands will

Accepted Answer

Constricting the blood vessels in their large ears would reduce transfer of external heat to the blood in their ears, helping to prevent the jackrabbits' bodies from overheating in hot, arid conditions. Dilating the blood vessels would have the opposite effect, transferring more heat into their bodies and exacerbating the problem. Increasing motor movements or pigmentation in their ears would not directly address the issue of heat transfer. Involuntary shivering is a response to cold temperatures, not heat.

Question 7

In a multicellular animal,the circulatory system exchanges materials with the external environment using specialized exchange surfaces.Which of the following is not an example of such an exchange surface?

Accepted Answer

Muscles are not specialized exchange surfaces for material exchange with the external environment, unlike lungs, skin, intestine, and kidneys.

Question 8

The absorptive epithelia in the gut are considered "polarized" because

Accepted Answer

The structures on the apical surface (facing the lumen of the gut) are different than those on the basal surface (facing the blood). This is known as polarity, where one end of the cell is functionally and structurally different from the other end. This allows for directional transport of nutrients and waste, with nutrients being transported from the lumen to the blood and waste being transported from the blood to the lumen.

Question 9

The specialized function shared by the cells that line the lungs and those that line the lumen of the gut is that both types of cells

Accepted Answer

Both types of cells need to provide a large surface area for absorption/exchange. The lungs need a large surface area for gas exchange, while the gut needs a large surface area for absorption of nutrients. Both types of cells achieve this through specialized modifications such as microvilli in the gut and the extensive branching of the respiratory bronchioles in the lungs.

Question 10

An exchange surface in direct contact with the external environment is found in the

Accepted Answer

The lungs have alveoli, which are small air sacs that directly contact the external environment and allow for gas exchange between oxygen in the air and carbon dioxide in the blood. The other options listed do not have direct contact with the external environment for gas exchange.

Question 11

Penguins,seals,and tuna have body forms that permit rapid swimming,because

Accepted Answer

The body form of penguins, seals, and tuna is a convergent evolutionary solution to the need to reduce drag while swimming, allowing for rapid swimming ability.

Question 12

Which choice best describes a reasonable mechanism for animal structures becoming better suited over evolutionary time to specific functions?

Accepted Answer

The best mechanism for animal structures becoming better suited over evolutionary time to specific functions is through natural selection. This means that animals with mutations that give rise to effective structures will have an advantage in survival and reproduction, and therefore become more abundant in the population. Over time, this can lead to the evolution of structures that are well-suited to specific functions. This is supported by observations and evidence from the fossil record, as well as studies of contemporary species. Therefore, choice C is the best option.

Question 13

To increase the effectiveness of exchange surfaces lining the lungs and the intestines,evolutionary pressures have

Accepted Answer

Increasing the exchange surface area with folds and branches allows for more surface area to be available for gas or nutrient exchange, which increases the effectiveness of the exchange surfaces in the lungs and intestines. This is seen in the alveoli of the lungs and the microvilli lining the intestines. Increasing the thickness of the membranes or the number of cell layers would decrease the effectiveness of exchange as it would create more barriers for diffusion. Decreasing the metabolic rate or increasing the volume of cells would not necessarily increase the effectiveness of exchange surfaces.

Question 14

All animals,whether large or small,have

Accepted Answer

All animals have each living cell in contact with an aqueous medium, as they all require water for survival and all cellular processes occur in an aqueous environment. The other options are all incorrect: (A) many animals have moist body surfaces, such as amphibians and some reptiles; (B) animals have a variety of body plans, not all of which resemble a two-layered sac; (C) not all animals are covered with hair, and not all hair is used for warmth; (D) not all animals have the ability to enter dormancy, and this is not a universal characteristic of animals.

Question 15

Tissues are composed of cells,and tissues functioning together make up

Accepted Answer

Tissues functioning together make up organs, not membranes or organ systems. Organelles are the smallest functional units within cells, and organisms are the highest level of organization above organ systems.

Question 16

Multicellular organisms must keep their cells awash in an "internal pond" because

Accepted Answer

Multicellular organisms require an aqueous medium to facilitate cellular exchange of nutrients, gases, and wastes. This is essential for maintaining homeostasis and ensuring the survival of the organism.

Question 17

The similar fusiform body shape of diverse animals,such as sharks,penguins,and aquatic mammals,has evolved because

Accepted Answer

The fusiform body shape is a common adaptation for aquatic animals that need to swim rapidly. This shape reduces drag and allows for efficient movement through water. Therefore, it is likely that the similar fusiform body shape of sharks, penguins, and aquatic mammals has evolved as a result of natural selection for efficient swimming.

Question 18

Interstitial fluid is

Accepted Answer

Interstitial fluid is the fluid that surrounds and bathes the cells of the body. It serves as the medium for the exchange of nutrients and waste products between the blood and body cells. It is not found only in the lumen of the small intestine, nor is it identical to the composition of blood or the internal environment inside animal cells.

Question 19

Of the following choices,the epithelium with the shortest diffusion distance is

Accepted Answer

Simple squamous epithelium consists of a single layer of flattened cells, which offers the shortest diffusion distance, allowing for efficient exchange of substances across the epithelium.

Question 20

The specialized structures of complex animals have evolved because

Accepted Answer

The specialized structures of complex animals have evolved to permit adjustments to a wide range of environmental changes. This adaptability allows for survival in a variety of different environments and situations. Additionally, animals with more specialized structures are often more successful in competing for resources and reproducing, which contributes to their evolutionary success.

Quiz 40: Basic Principles of Animal Form and Function