Chapter 5 Review PP Sections 1, 2, and 3
Bell Work
5-1 Review Characteristics of Populations What is a population’s geographic distribution? It describes the area inhabited by a population What three factors can affect population size? # of births # of deaths # of individuals that enter or leave the population
5-1 Review Characteristics of Populations What is population density? The number of individuals per unit area
5-1 Review Changes in Population Immigration / Emigration Which one is the movement INTO an area? Which one is the movement out of the area? EXITING the area = Emigration Into = Immigration
5-1 Review Population Growth Under ideal conditions with unlimited resources, how will a population grow? Exponentially When resources become less available, how does population growth change? It slows or stops = Logistic Growth
5-1 Review What is the carrying capacity of the environment for a particular species? The largest number of individuals that the given environment can support. So, what might cause the carrying capacity for the human population to increase?
Section 5-2 Limiting Factors What is a limiting factor? It is a factor that causes population growth to decrease A limiting nutrient is an example of a limiting factor
Section 5-2 What is a density-dependent limiting factor? It is a limiting factor that depends on population size When do they become limiting? They become limiting only when the population density reaches a certain level. They operate most strongly when… a population is large and dense
5-2 Density-Dependent Factors Four Density Dependent Limiting Factors 1. Competition – crowded populations compete for resources like food, water, & space
5-2 Density-Dependent Factors Four Density Dependent Limiting Factors 2. Predation – predator-prey relationship
5-2 Density-Dependent Factors Four Density Dependent Limiting Factors 3. Parasitism One organism lives inside or on another organism – called the … host 4. Disease
5-2 Density- Independent Factors Density- Independent Limiting Factors affect all populations in similar ways, regardless of the population size What are examples of density-independent limiting factors?
5-2 Density- Independent Limiting Factors Examples include: Unusual weather, natural disasters, seasonal cycles, and human activities Drought, Hurricanes, Severe winter frost
5-2 Density-Independent Limiting Factors What is the characteristic response in the population size of many species to a density- independent limiting factor? The population size crashes
Yesterday’s Bell Work Biotic vs. Abiotic?
5-3 Human Population Growth How does the size of the human population change with time? It tends to increase
5-3 Improved sanitation and health care reduced the death rate Why did the population grow slowly for most of human existence? Life was harsh and limiting factors kept population sizes low. What are some reasons why the human population began to grow more rapidly about 500 years ago? Improved sanitation and health care reduced the death rate Industry made life easier and safer A more reliable food supply
5-3 Patterns of Population Growth Why can’t the human population continue growing exponentially forever? Earth has limited resources
5-3 Patterns of Population Growth What is demography? It is the scientific study of human populations What factors help predict why the populations of some countries grow faster than others? Factors include the population’s birthrates, death rates, and age structure
5-3 Patterns of Population Growth The hypothesis that explains why population growth has slowed dramatically in the United States, Japan, and much of Europe is called the… Demographic Transition Stage 1: Birthrate and death rate are high Stage 2: Death rate drops & the birth date remains high Stage 3: The birthrate also decreases What do the decrease of the birthrate and the death rate do to the overall population size?
5-3 Demographic Transition
5-3 Human Population Growth What factors lower the death rate? Advances in nutrition, sanitation, and medicine True or False: Population growth depends, in part, on how many different ages make up a given population. TRUE
5-3 Demographic Transition Flowchart Changes brought about by modernization lower the __________ rate. DEATH Births greatly exceed deaths, resulting in rapid population ___________. INCREASES As modernization continues, the birthrate ____ and the population growth __________. FALLS & DECREASES The birthrate falls to meet the death rate, and the population growth __________. STOPS
5-3 Human Population Growth The worldwide human population is still growing exponentially. Most people live in countries that have not yet completed the demographic transition. The demographic transition has happened in the United States.
5-3 Age Structure Diagrams Recall, from 5-1 that age-structure diagrams are one of four main characteristics of a population along with…. geographic distribution, density, & growth rate What do the age structure diagrams graph? They graph the numbers of individuals in different age groups in the population.
5-3 Age Structures page 131 Figure 5-13 What do the age structures of the United States and of Rwanda predict about the population growth of each country?
United States Age Structure The age structure in the United States predicts a slow but steady growth rate for the near future. There nearly are equal numbers of people in each age group.
Rwanda Age Structure The age structure of Rwanda predicts a population that will double in ~ 30 years. There are more young children than teenagers, and many more teenagers than adults.
Chapter 5 Vocabulary Review Pattern of Growth ____________________ Exponential
Chapter 5 Vocabulary Review # 2 Logistic Growth # 3 Carrying Capacity
Chapter 5 Vocabulary Review 4. _______ is the number of individuals per unit area. True: Population Density 5. Emigration causes population size to _____. False: Decrease 6. The movement of individuals out of an area is called _________. False: Emigration
Chapter 5 Vocabulary Review 7. A(An) ____________ is any factor that causes population growth to decrease. False: Limiting Factor 8. Density- ______ limiting factors include competition and parasitism. False: Dependent
Chapter 5 Vocabulary Review 9. A predator-prey relationship is a(an) ___-___ Limiting factor. True: Density-Dependent 10. The scientific study of human populations is called ________. True: Demography
Chapter 5 Vocabulary Review 11. How do birthrates and death rates change when a population goes through the demographic transition? First, the death rate falls, causing the population growth rate to increase. Then, the birthrate falls, causing the population growth rate to decrease.
Chapter 5 Vocabulary Review 12. What do demographers try to predict using age-structure diagrams? Using age-structure diagrams, demographers try to predict future population growth. 13. What does the term geographic distribution mean? Geographic distribution means the area inhabited by the population.
Chapter 5 Vocabulary Review 14. When does exponential growth occur? Exponential growth occurs when a population has unlimited resources, limited predators and disease, and a constant rate of reproduction. 15. Which countries have completed the demographic transition? The United States, Japan, & much of Europe
Chapter 5 Quiz Tomorrow
Chapter 5 Exit Ticket Closed Book & Notes Explain how the Wolf and the Moose populations on the Isle Royale were affected by density-dependent limiting factors & density-independent limiting factors.