2.2 Study Guild Flashcards
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How is population growth determined from birth?
The rate of natural increase is the difference between birth and death rates.
How is population growth determined from death?
The rate of natural increase is the difference between birth and death rates.
How is population growth determined from emigration?
The formula for population growth rate is r = (b i) - (d e), where r is the growth rate, b is the birth rate, i is the immigration rate, d is the death rate, and e is the emigration rate.
How is population growth determined from immigration?
The formula for population growth rate is r = (b i) - (d e), where r is the growth rate, b is the birth rate, i is the immigration rate, d is the death rate, and e is the emigration rate.
How does one sketch basic graphs showing exponential growth?
- Create a table of points.
- Plot at least 3 point from the table including the y-intercept (0,1) .
- Draw a smooth curve through the points.
- State the domain, (−∞,∞) , the range, (0,∞) , and the horizontal asymptote, y=0 .
How does one sketch basic graphs showing logistic growth?
1.- Label the x-axis as “Time” or “Generations” and the y-axis as “Population Size.”
2. Plot an exponential growth curve, starting at low initial population size and rising steeply upward. This curve represents unrestricted growth with no limiting factors.
- Label this curve as “Exponential Growth.”
3. Draw a horizontal line across the graph, parallel to the x-axis. This line represents the carrying capacity (K), which is the maximum population size that the environment can sustain indefinitely.
- Label this line as “Carrying Capacity (K).”
4. Plot a logistic growth curve, starting similarly to the exponential growth curve but eventually leveling off near the carrying capacity line.
- The logistic growth curve should rise steeply initially, then gradually flatten out as it approaches the carrying capacity line.
- Label this curve as “Logistic Growth.”
5. - Shade the area under the exponential growth curve to represent the region where exponential growth occurs. This area extends from the start of the curve to the point where it intersects the carrying capacity line.
- Label this shaded area as “Exponential Growth Area.”
6. - Add appropriate labels to the x-axis (time or generations) and the y-axis (population size).
- Title your graph, for example, “Comparison of Exponential and Logistic Growth Models.”
- Include a legend if necessary to distinguish between the exponential growth and logistic growth curves.
Where population growth is highest in logistic growth?
When a population reaches its carrying capacity ,K.
Where population growth is highest in exponential growth?
During exponential growth, a population always grows at its maximum per capita rate.
What does the variable N stand for in the growth models?
Population size.
What does the variable N0 stand for in the growth models?
Original Population size
What does the variable r stand for in the growth models?
Per capita rate or per individual.
What does the variable t stand for in the growth models?
time
What does the variable K stand for in the growth models?
carrying capacity
What does the variable dN/dt stand for in the growth models?
the population growth rate.
What is the definition of Density Dependent?
Change in the birth and death rate of a population as a result of changes in population density;
What is the definition of Density independent?
Any force that affects the size of a population of living things regardless of the density of the population
Are Density Dependent variables mostly abiotic or biotic?
biotic
Are Density Independent variables mostly abiotic or biotic?
abiotic
Examples of Density Dependent variables.
disease, completion for water
Examples of Density Independent variables.
flood, drought
How exponential and logistic growth models change when r change and why?
When r is changed in an exponential growth model the population size increases because the number of individuals per area increase. When r is changed in a logistical model the population increases as more individuals can fit in one area.
How exponential and logistic growth models change when N change and why?
The population growth rate in the exponential growth model also increases without limit because of the lack of completion or limiting factors, but it decreases as N nears the carrying capacity in the logistic growth model due to the limiting factors and competition.
How exponential and logistic growth models change when K changes and why?
If K changes in an exponential growth model then the population will grow faster or slower with increasing or decreasing limiting factors. . If k changes in a logistical growth model then the population will increase or decrease with k due to the limits it provides.
