Chapter 5 Section 1 How Populations Grow List

  • Slides: 7
Download presentation
Chapter 5 Section 1 How Populations Grow • List the characteristics used to describe

Chapter 5 Section 1 How Populations Grow • List the characteristics used to describe a population • Identify factors that affect population size • Differentiate between exponential and logistic growth

Introduction 5 -1 Activity December 2, 2013 Write these questions and your answers on

Introduction 5 -1 Activity December 2, 2013 Write these questions and your answers on a sheet of paper. • How many people are in this classroom? (include me because I am a person) • What is the room’s area? (there are 39. 37 inches per meter)(area is length x width) • How many people are there in the room per square meter? (divide the number of people by the room’s area) Population density = # of individuals/unit area • Suppose there are 150 bullfrogs living in a pond that covers an area of 3 square kilometers. What is the density of the bullfrog population?

List the characteristics used to describe a population. • Three important characteristics of a

List the characteristics used to describe a population. • Three important characteristics of a population are its geographic distribution, density, growth rate, and population age structure. – Density – the number of individuals per unit area. This can vary greatly depending on the species and its ecosystem. – Geographic distribution – also called the range, the area inhabited by a population. This can vary greatly.

List the characteristics used to describe a population - continued – Growth rate –

List the characteristics used to describe a population - continued – Growth rate – the rate at which the size of a population changes – Population age structure – the age distribution of the individuals in that population

Population growth – Three factors can affect population size: - The number of births

Population growth – Three factors can affect population size: - The number of births (if you have more births than deaths the population size grows) - The number of deaths (if you have more deaths than births the population size shrinks) - The number of individuals that enter or leave a population - Immigration is the movement of individuals into an area - Emigration is the movement of individuals out of an area

Differentiate between exponential and logistic growth. Logistic Growth Exponential Growth • This occurs when

Differentiate between exponential and logistic growth. Logistic Growth Exponential Growth • This occurs when a population slows or stops following a period of exponential growth • As resources become less available, the growth of a population slows or stops. • This ususally appears as a “S -shaped” curve on a line graph. • This occurs when a population grows at a constant rate • Under ideal conditions with unlimited resources, a population will grow exponentially. • This usually appears as a “Jshaped” curve on a line graph.

Post Notes Assignment • Write questions numbered 1 -6 on page 123 and answer

Post Notes Assignment • Write questions numbered 1 -6 on page 123 and answer them. • Then write the definitions for the vocabulary terms found only in section 1 1. 2. 3. 4. 5. 6. population density immigration exponential growth logistic growth carrying capacity