Bio Chp 5.1 and 5.2

factors that decrease a population

death and emigration

factors that increase a population

birth and immagration

true or false If the death rate is less than the birthrate, the population is likely to shrink.

false greater

A high birthrate and immigration decrease population size.

false increase

True or false Limiting factors operate when growth is exponential.

logistical

What does the term carrying capacity refer to?

maximum # of individual of a particular species that a particular environment can support

Limiting factors produce the pressures of

natural selection.

Describe the conditions in which exponential growth occurs.

occurs under ideal conditions with no limits on food, water, or space and no predation or disease

after four day how will you be able to tell which test tube has more alage

see which one has more growth

What letter is used to refer to the characteristic shape of the logistic growth curve?

shaped like an S.

why did you use the cotton balls instead of rubber stoppers to plug your test tube

so that the plant could get carbon dioxide air in

what is the independent variable in the alage lab

the fertilizer in the test tube

immagration

the movement of individuals into an area

emigration

the movement of individuals out of an area

what happened to the moose population when the number of wolves was low

there was an abundance of moose

how could a thick layer of algae on the surface of a pond affect producers that live on or near the bottom of the pond

they wouldn't be able to get sunlight.

Populations grow if more individuals are born than die in a period of time.

true

True or false Competition is an example of a limiting factor.

true

True or false Population size can be limited by factors such as predation.

true

True or false Populations grow too large in the absence of limiting factors.

true

when do density dependent factors operate most strongly

when pop. density reaches a certain level

what are 4 density dependent limiting factors

competition predation herbivory disease

limiting factors determine

Acting separately or together, limiting factors determine an environment's carrying capacity.

What is an example of a limiting factor that humans use to control the carrying capacity of an environment for a particular type of organism? Explain your answer.

Agriculture and gardening are ways humans control the carrying capacity of an area that includes farms or gardens. Adding fertilizer, for example, promotes plant growth and increases the environment's carrying capacity for plants. Growing only one kind of crop can leave some animal populations without a food source, and the carrying capacity for those animals would decrease.

Stage 1 of logistical growth

Exponential growth: Individuals reproduce rapidly and few die. Both the population size and the growth rate increase rapidly.

Young animals may immigrate from the place where they were born to establish new territories.

False emmagrate

Stage 2 of logistical growth

Growth slows down: Population size increases slowly. The growth rate slows.

Stage 3 of logistical growth

Growth stops: The growth rate drops to zero, and the population size stabilizes at the carrying capacity.

A population continues at a stable size for many years. Suddenly, in a single season, the population size drops by half. Is the cause more likely to be density-dependent, density-independent, or both? Explain your answer.

It could be either or both. A density-independent factor such as extreme weather or a natural disaster could reduce numbers quickly. A density-dependent factor such as disease, parasitism, human activities, or a newly introduced predator or herbivore could also reduce numbers quickly.

What term describes a limiting factor that affects all populations in similar ways, regardless of population size?

It is a density-independent limiting factor.

carrying capacity

Population size stabilizes at the the maximum number of individuals of a given species that an environment can support.

What is the usual response in the population size of many species to a density independent limiting factor?

The population size decreases.

True or false Immigration increases population size

True

True or false A limiting factor controls the growth of a population.

True

Exponential Growth

When conditions are ideal, the larger a population gets, the faster it grows. When a population's numbers grow larger with each generation, Ideal conditions include unlimited resources and absence of depredation and disease.

what happens to a population diagram when emigration occurs

When emigration is greater than immigration, there are more dots leaving the population (arrows out) than entering it (arrows in). The result will be a decrease in population size

Can exponential growth occur in a population of organisms that take a long time to reproduce? Why or why not?

Yes, it can. If population size grows larger and the growth rate increases with each generation, exponential growth occurs

what is a density dependent limiting factor

a limiting factor that depends on the # of organisms per unit

density-independent limiting factors.

competition predation parasitism and disease unusual weather natural disaster

examples of Density-dependent limiting factors

competition • predation and herbivory • parasitism and disease • stress from overcrowding

is the number of moose on the island a density dependent or density independent limiting factor for the wolf explain

dependent because they maybe there will be enough food for the wolves or maybe not

True or false Limiting factors determine the immigration capacity of a population.

determine carrying capacity

growth rate

determines whether a population grows shrinks or stays the same size.

When real-world populations of plants and animals are analyzed, why do they most often have the logistic growth curve

exponential growth will not last forever

limiting factor

is a factor that controls the growth of a population. ex. density of the population

population distribuation

is how individuals are spaced in their range

geographic range

is the area in which a population lives

population density

is the number of individuals per unit area

age structure

is the number of males and females of each age in a population

what happened to the number of wolves on Isle Royale between 1975 and 1985

it droped by half

how did the addition of fertilizer affect the growth of the algae

it increased its growth and alage grew faster

what is the relationship between moose and wolves on isle royal

it is a cycle and predation wolves predators moose prey

why will you grow chlorella in spring water instead of pond water

it is easier to grow in spring water because their is more alage in pond water, and spring water is cleaner

What letter is used to refer to the characteristic shape of an exponential growth curve?

letter J.

Logistic growth

occurs when population growth slows and then stops after a period of exponential growth has occurred. Resources become less available as a population grows

Density-dependent limiting factors

operate strongly when the number of individuals per unit area reaches a certain point.