Textbook Question
Based on current growth rates, Earth's human population in 2019 will be closest to
a. 2.5 million
b. 4.5 billion
c. 7.5 billion
d. 10.5 billion
Ch. 53 - Population Ecology
Urry11th EditionCampbell BiologyISBN: 9789357423311
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 1 - Evolution, the Themes of Biology, and Scientific Inquiry8
- Ch. 2 - The Chemical Context of Life8
- Ch. 3 - Water and Life6
- Ch. 4 - Carbon and the Molecular Diversity of Life9
- Ch. 5 - The Structure and Function of Large Biological Molecules9
- Ch. 6 - A Tour of the Cell6
- Ch. 7 - Membrane Structure and Function6
- Ch. 8 - An Introduction to Metabolism6
- Ch. 9 - Cellular Respiration and Fermentation10
- Ch. 10 - Photosynthesis7
- Ch. 11 - Cell Communication7
- Ch. 12 - The Cell Cycle10
- Ch. 13 - Meiosis and Sexual Life Cycles10
- Ch. 14 - Mendel and the Gene Idea14
- Ch, 15 - The Chromosomal Basis of Inheritance7
- Ch. 16 - The Molecular Basis of Inheritance9
- Ch. 17 - Gene Expression: From Gene to Protein9
- Ch. 18 - Regulation of Gene Expression10
- Ch. 19 - Viruses6
- Ch. 20 - DNA Tools and Biotechnology8
- Ch. 21 - Genomes and Their Evolution8
- Ch. 22 - Descent with Modification: A Darwininan View of Life6
- Ch. 23 - The Evolution of Populations5
- Ch. 24 - The Origin of Species6
- Ch. 25 - The History of Life on Earth6
- Ch. 26 - Phylogeny and the Tree of Life7
- Ch. 27 - Bacteria and Archaea8
- Ch. 28 - Protists7
- Ch. 29 - Plant Diversity I: How Plants Colonized Land7
- Ch. 30 - Plant Diversity II: The Evolution of Seed Plants7
- Ch. 31 - Fungi5
- Ch. 32 - An Overview of Animal Diversity4
- Ch. 33 - An introduction to Invertebrates6
- Ch. 34 - The Origin and Evolution of Vertebrates7
- Ch. 35 - Vascular Plant Structure, Growth, and Development8
- Ch. 36 - Resource Acquisition and Transport in Vascular Plants8
- Ch. 37 - Soil and Plant Nutrition10
- Ch. 38 - Angiosperm Reproduction and Biotechnology8
- Ch. 39 - Plant Responses to Internal and External Signals8
- Ch. 40 - Basic Principles of Animal Form and Function8
- Ch. 41 - Animal Nutrition7
- Ch. 42 - Circulation and Gas Exchange7
- Ch. 43 - The Immune System6
- Ch. 44 - Osmoregulation and Excretion6
- Ch. 45 - Hormones and the Endocrine System8
- Ch. 46 - Animal Reproduction8
- Ch. 47 - Animal Development8
- Ch. 48 - Neurons, Synapses, and Signaling6
- Ch. 49 - Nervous Systems8
- Ch. 50 - Sensory and Motor Mechanisms5
- Ch. 51 Animal Behavior6
- Ch. 52 - An Introduction to Ecology and the Biosphere7
- Ch. 53 - Population Ecology10
- Ch. 54 - Community Ecology9
- Ch. 55 - Ecosystems and Restoration Ecology8
- Ch. 56 - Conservation Biology and Global Change6
Chapter 53, Problem 8
During exponential growth, a population always
a. Has a constant per capita population growth rate
b. Quickly reaches its carrying capacity
c. Cycles through time
d. Loses some individuals to emigration
Verified step by step guidance1
Understand the concept of exponential growth: Exponential growth occurs when the growth rate of a population is proportional to its current size, leading to the population increasing at a constant rate over time.
Identify the characteristics of exponential growth: In exponential growth, the per capita growth rate remains constant, meaning each individual contributes equally to the growth of the population.
Evaluate option a: A constant per capita population growth rate is a defining feature of exponential growth, as the rate does not change as the population size increases.
Consider option b: Exponential growth does not involve reaching carrying capacity quickly; instead, it describes the phase before any limiting factors affect the growth rate.
Analyze options c and d: Exponential growth does not involve cycles through time or losses due to emigration, as it assumes ideal conditions without external factors affecting the population size.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Exponential Growth
Exponential growth refers to a population increase where the rate of growth is proportional to the current size, leading to a rapid rise in numbers. This occurs when resources are abundant, and there are no significant constraints, resulting in a constant per capita growth rate. It is characterized by a J-shaped curve when plotted over time.
Recommended video:
Guided course
03:05
Exponential Population Growth
Carrying Capacity
Carrying capacity is the maximum population size that an environment can sustain indefinitely, given the available resources such as food, habitat, water, and other necessities. Once a population reaches its carrying capacity, growth slows down or stops due to limited resources, leading to a stable equilibrium or logistic growth pattern.
Recommended video:
Guided course
06:24Estimating Earth’s Human Carrying Capacity
Per Capita Growth Rate
Per capita growth rate is the average contribution of each individual to the population's growth rate. In exponential growth, this rate remains constant, meaning each individual contributes equally to the population increase. It is a crucial factor in determining how quickly a population can grow under ideal conditions.
Recommended video:
Guided course
03:26Population Growth Rate vs. Per Capita Population Growth Rate
Related Practice
Textbook Question
The observation that members of a population are uniformly distributed suggests that
a. Resources are distributed unevenly.
b. The members of the population are competing for access to a resource.
c. The members of the population are neither attracted to nor repelled by one another.
d. The density of the population is low.
Textbook Question
According to the logistic growth equation
a. The number of individuals added per unit time is greatest when N is close to zero.
b. The per capita population growth rate increases as N approaches K.
c. Population growth is zero when N equals K.
d. The population grows exponentially when K is small.
1
views
Textbook Question
Which of the following statements about human populations in industrialized countries is incorrect?
a. Birth rates and death rates are high.
b. Average family size is relatively small.
c. The population has undergone the demographic transition.
d. The survivorship curve is Type I.
Textbook Question
Which of the following statements about human populations in industrialized countries is correct?
a. Birth rates and death rates are high
b. Average family size is relatively large
c. The population has undergone the demographic transition
d. The survivorship curve is Type II