Question 1

What are generalist species?

Accepted Answer

Species that can live in many different places and don't have any specific requirements

(flies, cockroaches, raccoons, etc.; opposite of specialist species)

Question 2

What are specialist species?

Accepted Answer

Species of animals that require very special conditions to survive

(pandas, koalas, etc.; opposite of generalist species)

Question 3

Are specialist or generalist species more likely to survive natural disruptions?

Accepted Answer

Generalist species because they do not require as specific conditions and are therefore more adaptable

Question 4

Are invasive species more likely to be generalists or specialists?

Accepted Answer

Generalists because generalists have less specific requirements, meaning that they can thrive in foreign habitats more effectively

(it's hard to imagine pandas (specialists) as being invasive)

Question 5

What are reproductive strategies?

Accepted Answer

How animals mate and raise offspring

(K-selected vs. r-selected)

Question 6

What are the characteristics of K-selected species?

Accepted Answer

Have few offspring, but put a lot of parental care into those offspring

Typically larger

(e.g., elephants, humans, bison)

Question 7

What are the characteristics of r-selected species?

Accepted Answer

Have a lot off of offspring, but invest little parental care into each offspring

Typically small

(e.g., rodents, insects, weeds)

Question 8

What is biotic potential?

Accepted Answer

The maximum reproductive rate of a population in ideal conditions

(assuming infinite resources with no limiting factors)

Question 9

Are all species only r-selected or K-selected?

Accepted Answer

No, species can be in between r and K-selected

(it's a spectrum, not either/or options)

Question 10

What are survivorship curves?

Accepted Answer

Lines that display the relative survival rates of groups of individuals of the same age in a population

(three main types)

Question 11

What are the three survivorship curves?

Accepted Answer

Type I: Most of the population dies off near old age (typically K-selected due to extensive parental care)

Type II: Constant death rate regardless of age

Type III: Lots of early deaths with few living to old age (typically r-selected due to lack of parental care)

Question 12

What is carrying capacity (K)?

Accepted Answer

The maximum size of a population given the resources available in an environment

Question 13

What is overshoot?

(in populations)

Accepted Answer

When a population exceeds its carrying capacity

(this can cause resource depletion)

Question 14

What happens as a result of overshoot?

Accepted Answer

Severe or catastrophic dieback of the population

(there are no more resources left, so the population rapidly decreases)

Question 15

What is population growth?

Accepted Answer

The rate at which a population can grow, given environmental limitations such as the available resources and space

Question 16

What is exponential growth?

Accepted Answer

When populations grow at a constant rate (r), making the population grow faster and faster as it gets larger

(bacteria in a petri dish)

Question 17

Does exponential growth occur in nature?

Accepted Answer

Yes, but only in the short-term

Resource availability will make the growth logistic in the long-term

Question 18

What is logistic growth?

Accepted Answer

When a population's growth rate (r) decreases as it approaches carrying capacity

Question 19

What is growth rate (r)?

Accepted Answer

The percent change in a population over time

(10% growth rate -> the population increases exponentially by 10% each year)

Question 20

What are age structure diagrams (population pyramids)?

Accepted Answer

Models that show the distribution of age and sex in a population

Question 21

Why are age structure diagrams useful?

Accepted Answer

They can be used to interpret a population's growth rate and stage in the demographic transition model

Question 22

What is total fertility rate?

Accepted Answer

The average number of children born to a woman over her lifetime

Question 23

What influences total fertility rate?

Accepted Answer

The age at which women have their first child

Educational opportunities for women

Access to family planning

Government acts and policies

Question 24

What is replacement rate?

Accepted Answer

The total fertility rate required for a population not to shrink

(~2.1; if TFR is below replacement rate, a population will shrink)

Question 25

What is infant mortality rate?

Accepted Answer

The number of infant deaths per 1,000 live births

(high IMR = lots of deaths)

Question 26

What influences infant mortality rate?

Accepted Answer

Whether or not mothers have access to good healthcare and nutrition

Question 27

What are crude birth rate and crude death rate?

Accepted Answer

Crude birth rate: the number of births per 1000 people

Crude death rate: the number of deaths per 1000 people

Question 28

What factors influence whether a population is growing or declining?

Accepted Answer

Crude birth and death rate

IMR

TFR

Access to education

Postponement of marriage

Question 29

What is Malthusian theory?

Accepted Answer

Population growth is exponential, but food/resource growth is linear, so population will eventually exceed resources leading to decline

(criticized for being mostly incorrect and often having racist implications)

Question 30

What are density-independent factors?

Accepted Answer

Factors that affect population growth regardless of the population size, such as natural disasters

Question 31

What are density-dependent factors?

Accepted Answer

Factors that affect population growth due to the population's size, such as competition for resources and disease transmission

Question 32

What is the rule of 70?

Accepted Answer

A formula used to approximate the time it takes for a population to double

Question 33

What is the formula for the Rule of 70?

Accepted Answer

(with a 2.5% growth rate: 70/2.5 = 28 years to double)

Question 34

How do you calculate a population's annual percent change?

Accepted Answer

Question 35

How do you calculate population growth rate?

Accepted Answer

Question 36

What is the demographic transition model (DTM)?

Accepted Answer

The shift decrease in birth and death rates as a country shifts from a preindustrial to industrial economy

Question 37

What is the first stage of the DTM?

Accepted Answer

Pre-industrial: Birth rates and death rates are both high

(no populations are in this stage any more, beside a few isolated tribes)

Question 38

What is the second stage of the DTM?

Accepted Answer

Industrializing: Birth rates stay high, but death rates fall, leading to a boom in population

Question 39

What is the third stage of the DTM?

Accepted Answer

Industrial: Birth rate falls, decreasing population growth rate

Question 40

What is the fourth stage of the DTM?

Accepted Answer

Post-industrial: Stable population, with low birth and death rates

Unit 3 - Populations, AP Environmental Science Flashcards