Biology Chapter Review for Exam 3

The ability of rats to learn how to run a maze is an example of ________.

cognitive learning

Which of the following methods will tell an ecologist about both the size and density of a population?

quadrat

The average time a molecule spends in its reservoir is known as ________.

residence time

The ability of an ecosystem to return to its equilibrium state after an environmental disturbance is called ________.

resilience

The majority of water found on Earth is

salt water

A key feature of estuaries is

salt water and fresh water

ecology

study of interaction between living things and their environment

Understory plants in a temperate forest have adaptations to capture limited ________.

sunlight

In the English Channel ecosystem, the number of primary producers is smaller than the number of primary consumers because________.

the primary producers have a high turnover rate

What law of chemistry determines how much energy can be transferred when it is converted from one form to another?

the second law of thermodynamics

Which of the following is not a way that humans have increased the carrying capacity of the environment?

using large amounts of natural resources

Primates are examples of:

K-selected species

Which of the following biomes is characterized by abundant water resources?

Tropical Wet Forest

Which of the following biomes is characterized by short growing seasons?

Arctic tundras

Many endemic species are found in areas that are geographically isolated. Suggest a plausible scientific explanation for why this is so.

Areas that have been geographically isolated for very long periods of time allow unique species to evolve; these species are distinctly different from those of surrounding areas and remain so, since geographic isolation keeps them separated from other species.

Scientists have discovered the bodies of humans and other living things buried in bogs for hundreds of years, but not yet decomposed. Suggest a possible biological explanation for why such bodies are so well-preserved.

Bogs are low in oxygen and high in organic acids. The low oxygen content and the low pH both slow the rate of decomposition

In what ways are the subtropical desert and the arctic tundra similar?

Both the subtropical desert and the arctic tundra have a low supply of water. In the desert, this is due to extremely low precipitation, and in the arctic tundra, much of the water is unavailable to plants because it is frozen. Both the subtropical desert and the arctic tundra have low net primary productivity

Carbon is present in the atmosphere as ________.

CO2

Describe Pavlov's dog experiments as an example of classical conditioning

Dogs salivated in response to food. This was the unconditioned stimulus and response. Dogs exposed to food had a bell rung repeatedly at the same time, eventually learning to associate the bell with food. Over time, the dogs would salivate when the bell was rung, even in the absence of food. Thus, the bell became the conditioned stimulus, and the salivation in response to the bell became the conditioned response.

Ecologists often collaborate with other researchers interested in ecological questions. Describe the levels of ecology that would be easier for collaboration because of the similarities of questions asked. What levels of ecology might be more difficult for collaboration?

Ecologists working in organismal or population ecology might ask similar questions about how the biotic and abiotic conditions affect particular organisms and, thus, might find collaboration to be mutually beneficial. Levels of ecology such as community ecology or ecosystem ecology might pose greater challenges for collaboration because these areas are very broad and may include many different environmental components

The extremely low precipitation of subtropical desert biomes might lead one to expect fire to be a major disturbance factor; however, fire is more common in the temperate grassland biome than in the subtropic desert biome. Why is this?

Fire is less common in desert biomes than in temperate grasslands because deserts have low net primary productivity and, thus, very little plant biomass to fuel a fire.

Compare and contrast food chains and food webs. What are the strengths of each concept in describing ecosystems?

Food webs show interacting groups of different species and their many interconnections with each other and the environment. Food chains are linear aspects of food webs that describe the succession of organisms consuming one another at defined trophic levels. Food webs are a more accurate representation of the structure and dynamics of an ecosystem. Food chains are easier to model and use for experimental studies

Describe freshwater, ocean, and terrestrial ecosystems

Freshwater ecosystems are the rarest, but have great diversity of freshwater fish and other aquatic life. Ocean ecosystems are the most common and are responsible for much of the photosynthesis that occurs on Earth. Terrestrial ecosystems are very diverse; they are grouped based on their species and environment (biome), which includes forests, deserts, and tundras.

Compare grazing and detrital food webs. Why would they both be present in the same ecosystem?

Grazing food webs have a primary producer at their base, which is either a plant for terrestrial ecosystems or a phytoplankton for aquatic ecosystems. The producers pass their energy to the various trophic levels of consumers. At the base of detrital food webs are the decomposers, which pass this energy to a variety of other consumers. Detrital food webs are important for the health of many grazing food webs because they eliminate dead and decaying organic material, thus, clearing space for new organisms and removing potential causes of disease. By breaking down dead organic matter, decomposers also make mineral nutrients available to primary producers; this process is a vital link in nutrient cycling.

Give an example of how density-dependent and density-independent factors might interact

If a natural disaster such as a fire happened in the winter, when populations are low, it would have a greater effect on the overall population and its recovery than if the same disaster occurred during the summer, when population levels are high.

Describe the rate of population growth that would be expected at various parts of the S-shaped curve of logistic growth.

In the first part of the curve, when few individuals of the species are present and resources are plentiful, growth is exponential, similar to a J-shaped curve. Later, growth slows due to the species using up resources. Finally, the population levels off at the carrying capacity of the environment, and it is relatively stable over time.

The population is an important unit in ecology as well as other biological sciences. How is a population defined, and what are the strengths and weaknesses of this definition? Are there some species that at certain times or places are not in populations?

It is beneficial to consider a population to be all of the individuals living in the same area at the same time because it allows the ecologist to identify and study all of the abiotic and biotic factors that may affect the members of the population. However, this definition of a population could be considered a drawback if it prohibits the ecologist from studying a population's individuals that may be transitory, but still influential. Some species with members that have a wide geographic range might not be considered to be a population, but could still have many of the qualities of a population.

What are the factors that cause dead zones? Describe eutrophication, in particular, as a cause

Many factors can kill life in a lake or ocean, such as eutrophication by nutrient-rich surface runoff, oil spills, toxic waste spills, changes in climate, and the dumping of garbage into the ocean. Eutrophication is a result of nutrient-rich runoff from land using artificial fertilizers high in nitrogen and phosphorus. These nutrients cause the rapid and excessive growth of microorganisms, which deplete local dissolved oxygen and kill many fish and other aquatic organisms.

Why are drinking water supplies still a major concern for many countries

Most of the water on Earth is salt water, which humans cannot drink unless the salt is removed. Some fresh water is locked in glaciers and polar ice caps, or is present in the atmosphere. The Earth's water supplies are threatened by pollution and exhaustion. The effort to supply fresh drinking water to the planet's ever-expanding human population is seen as a major challenge in this century.

Which type of mimicry involves multiple species with similar warning coloration that are all toxic to predators?

Müllerian mimicry

How does the amount of food a warm blooded-animal (endotherm) eats relate to its net production efficiency (NPE)?

NPE measures the rate at which one trophic level can use and make biomass from what it attained in the previous level, taking into account respiration, defecation, and heat loss. Endotherms have high metabolism and generate a lot of body heat. Although this gives them advantages in their activity level in colder temperatures, these organisms are 10 times less efficient at harnessing the energy from the food they eat compared with cold-blooded animals, and thus have to eat more and more often.

Describe nitrogen fixation and why it is important to agriculture

Nitrogen fixation is the process of bringing nitrogen gas from the atmosphere and incorporating it into organic molecules. Most plants do not have this capability and must rely on free-living or symbiotic bacteria to do this. As nitrogen is often the limiting nutrient in the growth of crops, farmers make use of artificial fertilizers to provide a nitrogen source to the plants as they grow

Compare and contrast ocean upwelling and spring and fall turnovers

Ocean upwelling is a continual process that occurs year-round. Spring and fall turnover in freshwater lakes and ponds, however, is a seasonal process that occurs due to temperature changes in the water that take place during springtime warming and autumn cooling. Both ocean upwelling and spring and fall turnover enable nutrients in the organic materials at the bottom of the body of water to be recycled and reused by living things.

Describe the conditions and challenges facing organisms living in the intertidal zone.

Organisms living in the intertidal zone must tolerate periodic exposure to air and sunlight and must be able to be periodically dry. They also must be able to endure the pounding waves; for this reason, some shoreline organisms have hard exoskeletons that provide protection while also reducing the likelihood of drying out.

Why is long-term parental care not associated with having many offspring during a reproductive episode?

Parental care is not feasible for organisms having many offspring because they do not have the energy available to take care of offspring. Most of their energy budget is used in the formation of seeds or offspring, so there is little left for parental care. Also, the sheer number of offspring would make individual parental care impossible.

Compare the three types of ecological pyramids and how well they describe ecosystem structure. Identify which ones can be inverted and give an example of an inverted pyramid for each.

Pyramids of numbers display the number of individual organisms on each trophic level. These pyramids can be either upright or inverted, depending on the number of the organisms. Pyramids of biomass display the weight of organisms at each level. Inverted pyramids of biomass can occur when the primary producer has a high turnover rate. Pyramids of energy are usually upright and are the best representation of energy flow and ecosystem structure.

Describe the age structures in rapidly growing countries, slowly growing countries, and countries with zero population growth.

Rapidly growing countries have a large segment of the population at a reproductive age or younger. Slower growing populations have a lower percentage of these individuals, and countries with zero population growth have an even lower percentage. On the other hand, a high proportion of older individuals is seen mostly in countries with zero growth, and a low proportion is most common in rapidly growing countries.

Describe the competitive exclusion principle and its effects on competing species

The competitive exclusion principle states that no two species competing for the same resources at the same time and place can coexist over time. Thus, one of the competing species will eventually dominate. On the other hand, if the species evolve such that they use resources from different parts of the habitat or at different times of day, the two species can exist together indefinitely.

Describe how a researcher would determine the size of a penguin population in Antarctica using the mark and release method.

The researcher would mark a certain number of penguins with a tag, release them back into the population, and, at a later time, recapture penguins to see what percentage of the recaptured penguins was tagged. This percentage would allow an estimation of the size of the penguin population.

What term describes the use of mathematical equations in the modeling of linear aspects of ecosystems?

analytical modeling

The movement of mineral nutrients through organisms and their environment is called a ________ cycle

biogeochemical

Which term describes the process whereby toxic substances increase along trophic levels of an ecosystem?

biomagnification

The weight of living organisms in an ecosystem at a particular point in time is called:

biomass

The maximum rate of increased characteristic of a species is called its ________.

biotic potential

The population size of a species capable of being supported by the environment is called its ________.

carrying capacity

Organisms that can make their own food using inorganic molecules are called

chemoautotrophs

A forest fire is an example of ________ regulation

density-independent

Decomposers are associated with which class of food web?

detrital

What is an example of a biotic factor?

disease-causing microbe

A country with zero population growth is likely to be ________.

economically underdeveloped

Which type of country has the greatest proportion of young individuals?

economically underdeveloped

The study of nutrient cycling though the environment is an example of which of the following?

ecosystem ecology

The process whereby oxygen is depleted by the growth of microorganisms due to excess nutrients in aquatic systems is called ________.

eutrophication

Which of the following is associated with the reproductive potential of a species?

fecundity

Which of the following is associated with long-term parental care?

few offspring

heterospecifics

individuals that are members of different species

conspecifics

individuals that are members of the same species

Where would you expect to find the most photosynthesis in an ocean biome?

intertidal zone

Which of the following is associated with multiple reproductive episodes during a species' lifetime?

iteroparity

The sacrifice of the life of an individual so that the genes of relatives may be passed on is called ________.

kin selection

An ecologist hiking up a mountain may notice different biomes along the way due to changes in all of the following except:

latitude

Which of the following is best at showing the life expectancy of an individual within a population?

life table

biotic

living components of the environment

Species with limited resources usually exhibit a(n) ________ growth curve.

logistic

A re-created ecosystem in a laboratory environment is known as a ________.

microcosm

A symbiotic relationship where both of the coexisting species benefit from the interaction is called ________.

mutualism

The process whereby nitrogen is brought into organic molecules is called ________.

nitrogen fixation

abiotic

nonliving components of the environment

The training of animals usually involves ________.

operant conditioning

The primary producers in an ocean grazing food web are usually ________.

phytoplankton

The first species to live on new land, such as that formed from volcanic lava, are called ________.

pioneer species

Species that have many offspring at one time are usually

r-selected

The position of an organism along a food chain is known as its ________.

trophic level

Humans have which type of survivorship curve?

type 1