Biology Exam III

A food web shows how energy flows through an ecosystem.

True; A food web represents multiple pathways through which energy and matter flow through an ecosystem.

A positive population growth rate means a population is increasing.

True; A positive growth rate means a population is increasing.

An ecosystem consists of all the biotic and abiotic factors in an area and their interactions.

True; An ecosystem is a unit of nature and the focus of study in ecology. It consists of all the biotic and abiotic factors in an area and their interactions.

Aquatic biomes in the ocean are called marine biomes.

True; Aquatic biomes in the ocean are called marine biomes.

Logistic growth levels out at the carrying capacity.

True; At what population size does growth start to slow in the logistic model of growth? That depends on the population's carrying capacity. The carrying capacity (K) is the largest population size that can be supported in an area without harming the environment. Population growth hits a ceiling at that size in the logistic growth model.

Carbon cycles quickly between organisms and the atmosphere.

True; Carbon cycles quickly between organisms and the atmosphere.

Climate is the average weather in an area over a long period of time.

True; Climate is the average weather in an area over a long period of time.

Dung beetles eat animal feces.

True; Detritivores consume detritus—the dead leaves, animal feces, and other organic debris that collects on the soil or at the bottom of a body of water. On land, detritivores include earthworms, millipedes, and dung beetles.

Dispersal refers to offspring moving away from their parents.

True; For example, many species have some means of dispersal. This refers to offspring moving away from their parents.

Herbivores are a necessary link between producers and other consumers.

True; Herbivores consume producers such as plants or algae. They are a necessary link between producers and other consumers. Examples include deer, rabbits, and mice.

Human populations are fast growing.

True; Humans have been called the most successful "weed species" Earth has ever seen. Like weeds, human populations are fast growing. They also disperse rapidly. They have colonized habitats from pole to pole. Overall, the human population has had a pattern of exponential growth. The population increased very slowly at first. As it increased in size, so did its rate of growth.

Stage 5 may be a new stage of the demographic transition, raising issues for some populations.

True; In some countries, birth rates have fallen even lower than death rates. As result, their population growth rates are negative. In other words, the populations are shrinking in size. These populations have top-heavy population pyramids, like the one for Italy. This is a new stage of the demographic transition, referred to as Stage 5. You might think that a negative growth rate would be a good thing. In fact, it may cause problems. For example, growth-dependent industries decline. Supporting the large aging population is also a burden for the shrinking younger population of workers.

Interspecific competition often leads to extinction, or it may lead to greater specialization.

True; Interspecific competition often leads to extinction. The species that is less well adapted may get fewer of the resources that both species need. As a result, members of that species are less likely to survive, and the species may go extinct.

The deep ocean store carbon for thousands of years or more.

True; Most of this carbon ends up in the ocean. The deep ocean can store carbon for thousands of years or more.

Mutualism is a symbiotic relationship in which both species benefit.

True; Mutualism is a symbiotic relationship in which both species benefit.

Population growth rate is how fast a population changes in size over time.

True; Population growth rate (r) is how fast a population changes in size over time.

Rock that hardens from lava is an example of an area for primary succession.

True; Primary succession occurs in an area that has never before been colonized. Generally, the area is nothing but bare rock. This type of environment may come about when lava flows from a volcano and hardens into rock. a glacier retreats and leaves behind bare rock. a landslide uncovers an area of bare rock.

Autotrophs make their own food.

True; Producers are organisms that produce food for themselves and other organisms. They use energy and simple inorganic molecules to make organic compounds. The stability of producers is vital to ecosystems because all organisms need organic molecules. Producers are also called autotrophs.

Scavengers include vultures and raccoons.

True; Scavengers consume the soft tissues of dead animals. Examples of scavengers include vultures, raccoons, and blowflies.

If a parasite kills its host, the parasite may also die.

True; Some parasites kill their host, but most do not. It's easy to see why. If a parasite kills its host, the parasite is also likely to die.

K-selected population growth is controlled by density-dependent factors.

True; Species that live in stable environments are likely to be K-selected. Their population growth is controlled by density-dependent factors. Population size is generally at or near the carrying capacity.

Species that live in unstable environments are usually r-selected, and their population size is usually well below the carrying capacity.

True; Species that live in unstable environments are likely to r-selected. Their potential population growth is rapid. For example, they have large numbers of offspring. However, individuals are likely to die young. Thus, population size is usually well below the carrying capacity.

Temperature gets cooler as you move away from the equator.

True; Temperature falls from the equator to the poles.

The carrying capacity is the largest population size that can be supported in an area without harming the environment.

True; The carrying capacity (K) is the largest population size that can be supported in an area without harming the environment. Population growth hits a ceiling at that size in the logistic growth model.

Climate determines plant growth.

True; The distinguishing features of terrestrial biomes are determined mainly by climate.

The growing season may last all year in a hot, wet climate.

True; The growing season may last all year in a hot, wet climate but just a few months in a cooler or drier climate.

The ocean is a reservoir for water.

True; The ocean is a reservoir for water.

The water cycle takes place on, above, and below Earth's surface.

True; The water cycle is a global cycle. It takes place on, above, and below Earth's surface

Transpiration occurs when plants release water vapor through their stomata.

True; Transpiration occurs when plants release water vapor through leaf pores called stomata

With a type I survivorship curve, most of the offspring survive to adulthood so they can reproduce.

True; Type I: Parents produce relatively few offspring and provide them with a lot of care. As a result, most of the offspring survive to adulthood so they can reproduce.

When aquatic organisms die, they sink to the bottom, so water near the bottom may contain more nutrients than water at other depths.

True; Water near the bottom of lakes and the ocean may contain more nutrients than water closer to the surface. When aquatic organisms die, they sink to the bottom.

The best description of the relationship between runoff and groundwater is that

both result from precipitation and may end up in bodies of water. Precipitation that falls on land may flow over the surface of the ground. This water is called runoff. It may eventually flow into a body of water. Some precipitation that falls on land may soak into the ground, becoming groundwater. Groundwater may seep out of the ground at a spring or into a body of water such as the ocean.

Photosynthesis removes ______ from the atmosphere and uses it to make organic compounds.

carbon dioxide

The relationship between condensation and precipitation is that

condensation needs to occur prior to precipitation, both are parts of the water cycle. Condensation is the process in which water vapor changes to tiny droplets of liquid water. The water droplets may form clouds. If the droplets get big enough, they fall as precipitation—rain, snow, sleet, hail, or freezing rain.

Which organism would usually be in the fourth trophic level?

hawks

Wetlands are important, as they

provide a safe, lush habitat for many species of animals. remove excess nutrients from runoff before it empties into rivers or lakes. store excess water from floods.

In terms of carbon and the atmosphere, autotrophs

remove carbon through photosynthesis and release carbon by cellular respiration.

Climate is _______________, whereas weather is _______________.

the average weather in an area over a long period of time, the conditions of the atmosphere from day today.

An example of interspecific competition is

two species of big cats competing for the same antelope.

Which of the following is a parasite?

the roundworm; Some parasites live on the surface of their host. Others live inside their host. They may enter the host through a break in the skin or in food or water. For example, roundworms are parasites of mammals, including humans, cats, and dogs.

Biomes may be terrestrial, aquatic, or atmospheric.

False; Biomes may be terrestrial or aquatic.

Humans have a type ______ survivorship curve, as ________________.

I, most of the offspring survive to adulthood so they can reproduce.

Which is an example of a predator-prey relationship?

The relationship between a lion and a zebra.

Nekton are _______________, and benthos are _______________.

aquatic animals that swim, aquatic organisms that crawl.

Examples of biotic factors include

grass, trees, bees, and ants; Biotic factors are the living aspects of the environment. They consist of other organisms, including members of the same and different species. Abiotic factors are the nonliving aspects of the environment. They include factors such as sunlight, soil, temperature, and water.

Which describes the possible flow of energy in an ecosystem?

trees to caterpillars to frogs to snakes

When organisms must compete for resources, they will usually have a ____________ distribution.

uniform; Organisms are evenly spaced over the area they occupy. This is typical of species in which individuals compete for a scarce environmental resource, such as water in a desert.

Organisms that live deep in the ocean must be able to

withstand extreme water pressure, very cold water, and complete darkness.

All biomes, except a desert, have populations of interacting species.

False; Biomes as different as deserts and wetlands share something very important. All biomes have populations of interacting species. Species also interact in the same basic ways in all biomes.

Carnivores include lions, polar bears, hawks, frogs, salmon, and deer.

False; Carnivores consume animals. Examples include lions, polar bears, hawks, frogs, salmon, and spiders {not deer}.Herbivores consume producers such as plants or algae. They are a necessary link between producers and other consumers. Examples include deer, rabbits, and mice.

Cellular respiration releases oxygen into the atmosphere as carbon dioxide.

False; Cellular respiration releases carbon into the atmosphere as carbon dioxide.

Organisms consume 90% of the available energy at each trophic level.

False; Energy is passed up a food chain or web from lower to higher trophic levels. However, only about 10 percent of the energy at one level is available to the next level. What happens to the other 90 percent of energy? It is used for metabolic processes or given off to the environment as heat.

Interspecific competition occurs between members of the same species.

False; Interspecific competition occurs between members of different species.{Intraspecific competition occurs between members of the same species.}

Immigration is the regular movement of individuals or populations each year during certain seasons.

False; Migration is the regular movement of individuals or populations each year during certain seasons.

Most populations live under ideal conditions, so they grow at exponential rates.

False; Most populations do not live under ideal conditions. Therefore, most do not grow exponentially.

Oxygen makes up most of Earth's atmosphere.

False; Nitrogen makes up 78 percent of Earth's atmosphere.

Biomass increases at the upper levels of a food chain.

False; Organisms tend to be larger in size at higher trophic levels, but their smaller numbers result in less biomass. Biomass is the total mass of organisms at a trophic level. The decrease in biomass from lower to higher levels is also represented

Part of a cycle that holds an element or water for a short period of time is a reservoir pool.

False; Part of a cycle that holds an element or water for a short period of time is called an exchange pool. Part of a cycle that holds an element or water for a long period of time is called a reservoir.

Phytoplankton are tiny animals that feed on zooplankton.

False; Phytoplankton are bacteria and algae that use sunlight to make food. Zooplankton are tiny animals that feed on phytoplankton.

Plankton are tiny aquatic organisms that swim around in the photic zone.

False; Plankton are tiny aquatic organisms that cannot move on their own. They live in the photic zone.

Plants use nitrogen gas from the air to make organic compounds.

False; Plants cannot use nitrogen gas from the air to make organic compounds for themselves and other organisms. The nitrogen gas must be changed to a form called nitrates, which plants can absorb through their roots.

Populations gain individuals through births and emigration.

False; Populations gain individuals through births and immigration.

Predation is a relationship in which the prey consumes the predator.

False; Predation is a relationship in which members of one species (the predator) consume members of another species (the prey).

Sublimation occurs when water changes to water vapor.

False; Sublimation occurs when ice and snow change directly to water vapor. This also happens because of heat from the sun.

Lichens that can live on bare rock may be pioneer species after a flood.

False; Succession after a flood would be secondary succession because the soil is already in place. In this case, the pioneer species are plants such as grasses, birch trees, and fireweed - not lichens that live on bare rock.

Terrestrial biomes include all the land and water areas on Earth where organisms live.

False; Terrestrial biomes include all the land areas on Earth where organisms live.

A population's age-sex structure influences population growth, as older people are more likely to reproduce.

False; The age-sex structure influences population growth. This is because younger people are more likely to reproduce, while older people have higher rates of dying.

The first species to colonize a disturbed area such as this are called primary species.

False; The first species to colonize a disturbed area such as this are called pioneer species.

The photic zone is water deeper than 200 meters.

False; The photic zone extends to a maximum depth of 200 meters (656 feet) below the surface of the water. This is where enough sunlight penetrates for photosynthesis to occur.

Nitrogen fixation is done by nitrogen-fixing plants.

False; The process of changing nitrogen gas to nitrates is called nitrogen fixation. It is carried out by nitrogen-fixing bacteria. The bacteria live in soil and roots of legumes, such as peas.

Water droplets fall from the atmosphere as condensation.

False; The water droplets may form clouds. If the droplets get big enough, they fall as precipitation—rain, snow, sleet, hail, or freezing rain.

There are three major types of community interactions: predation, competition, and selection.

False; There are three major types of community interactions: predation, competition, and symbiosis.

The terrifying anglerfish lives between 100 and 400 feet below sea level.

False; This anglerfish lives between 1000 and 4000 meters below sea level.

With a type III survivorship curve, parents produce moderate numbers of offspring and provide some parental care.

False; Type III: Parents produce many offspring but provide them with little or no care.

Just like energy, matter is lost as it passes through an ecosystem.

False; Unlike energy, matter is not lost as it passes through an ecosystem. Instead, matter is recycled.

Temperature refers to the conditions of the atmosphere from day to day.

False; Weather refers to the conditions of the atmosphere from day to day.

Which statement is correct?

Nitrogen makes up most of Earth's atmosphere. Nitrogen must cycle through an ecosystem because it is used to make proteins and nucleic acids. Nitrogen gas from the atmosphere cannot be used by plants to make organic compounds.

Producers occupy the first trophic level.

True

Population growth can be represented by the equation r =

(b+i)-(d+e)

Which would represent a population?

. All the dogs in your neighborhood.

Aquatic biomes are defined in terms of which abiotic factors? (1) sunlight (2) dissolved oxygen and nutrients (3) temperature (4) moisture.

1 and 2

Which of the following are examples of density-dependent factors? (1) food, (2) disease, (3) rainfall, (4) temperature.

1 and 2

A population consists of all the communities of all the species in the same area.

False; A community is the biotic part of an ecosystem. It consists of all the populations of all the species in the same area. A community consists of all the populations of all the species in the same area.

Sunlight penetrates roughly _____ meters into the water.

200

Which statement best describes a trophic level?

A trophic level is the feeding position of an organism in a food chain or web.

Which of the following would NOT be a community?

All the plants, insects, and soil in your back yard; A community is the biotic part of an ecosystem. It consists of all the populations of all the species in the same area. Soil is not a biotic part.

In a complex ecosystem, it is likely that two different species will occupy the same niche.

False; A given habitat may contain many different species, but each species must have a different niche. Two different species cannot occupy the same niche in the same place for very long. This is known as the competitive exclusion principle.

A keystone species is one that plays an especially important role in its population.

False; A keystone species is one that plays an especially important role in its community.

A niche refers to the place an organism lives within its ecosystem.

False; A niche refers to the role of a species in its ecosystem.

Biotic factors include sunlight, soil, temperature, and water.

False; Abiotic factors are the nonliving aspects of the environment. They include factors such as sunlight, soil, temperature, and water.

A biome is

a group of similar ecosystems with the same general abiotic factors and primary producers.

_____ succession may occur after a forest fire.

Secondary

An example of an exchange pool is

The atmosphere for water; Part of a cycle that holds an element or water for a short period of time is called an exchange pool. For example, the atmosphere is an exchange pool for water.

Which statement best defines ecology?

The study of how living things interact with each other and with their environment.

During exponential growth,

as population size increases, the growth rate also increases.

Nitrogen fixation

is the process of changing nitrogen gas to nitrates.

The _____ is the role of a species in its ecosystem.

niche

Community interactions include

symbiosis. competition. predation.

The relationship between autotrophs and producers is

that they are the same organisms.

Which could possibly be a pioneer species during primary succession?

the first lichen on new rock