ENVS 1350- Chapter 2
what is the growth rate formula?
(b+i)-(d+e) (Births plus Immigration) Minus (deaths plus emigration rate)
What are the four methods of birth control?
1. Natural (Abstinence) 2. Chemical (pills) 3. Mechanical (condom) 4. Surgical (vasectomy/tubectomy)
What is the total fertility rate replacement level?
2.1
The united Nations determined that the number of refugees emigrating from impoverished and war-torn countries in 2016 exceeds how much?
35 Million
Approximately, what is the doubling time for the U.S. population in years?
85
How effective is the male condom in preventing unwanted pregnancies when used correctly?
88%
How effective is a male condom in preventing unwanted pregnancies when used correctly along with a spermicide?
98%
Which area of the world has the fastest doubling time?
Africa
What are anoxic zones?
Areas of the ocean that has no concentrations of oxygen. (AKA: Dead zones)
What are hypoxic zones?
Areas of the ocean that oxygen is still present but in a very little amount.
Why does the age-sex composition of the population have a profound effect on the birth and death rates of a country?
Because the probability of dying or giving birth within a given year depends upon the age and sex of the population members.
What are homeostatic controls?
Behavioral,Physiological, and social responses that control size within a population
How can a population grow? (2 things)
Birth & Immigration
The number of individuals added to a population through reproduction
Birth Rate
How is growth rate determined?
By the birth rate minus the death rate.
The max amount of organisms the environment can support
Carrying capacity
What can make a population decline? (2 things)
Death & Emigrants
Why are anoxic zone increasing?
Due to excess nutrients and warming waters
Refers to those pressures that limit population. (May include factors such as disease, wars, predatory behavior, toxic waste accumulation, or species competition)
Environmental Resistance
Which area of the world has the longest doubling time for people?
Europe
Rate of natural Increase. (Death rate subtracted from birth rate & expressed as a percentage)
Growth Rate
How do you figure out the total impact ?
I=PAT Population x Affluences x Technology
Which curve has a population (like Mosquitos) that grows too rapidly, beyond it's capacity?
J-Curve
which curve leads to a crash as the population exceeds carrying capacity?
J-Curve
What are individuals of the same species living together within a given area called?
Population
A group of organisms that can breed together with the production of offspring
Species
What as become one of the most popular methods for contraception in the United States among married couples who have achieved their desired level of parenthood?
Sterilization
Represents the average number of children a woman in a given population is likely to bear during her reproductive years.
TFR- Total Fertility Rates
Why do we add iodized salt to food?
To prevent Goiter
What type of survivorship curve is characteristic of most bird species?
Type 2
The Rule of 70:
doubling time = (70/the %growth rate)
The strategy that refers to organisms with relatively long life spans and have only few offspring but devote their energies to protecting and nurturing their offspring to enhance their individual survival until they can reproduce is called the:
k-strategy
populations that are typically small, short-lived organisms that produce large numbers of offspring and receive little or no parental care.
r-strategy Populations
