population biology Flashcards
a group of interacting organisms of the
same species living in a particular space
Population
Micro population:
Macro population:
Micro population: Aeta population (local population)
Macro population: human population
All the individuals of
a species that live
together in an area
Population
How to know one’s species in a population
Size - how many
Dispersion - interact w each other
Density - distributed/ dispersed
Briefly explain population dynamics
Study how and why population size changes over time
Study the factors affecting the growth, stability and decline of populations
What are the 3 phases that all populations undergo
Growth
Stability
Decline
It is the no. of individuals in a population
Size
What are the factors affecting the size of a population over time
Births - increase
Deaths - decrease
Migration
- immigration: live in a country that is not the country of origin
-emigration.: leave the country of origin and live someplace else
It is the no. of individuals per unit of area at a given time (example)
Density
(ex: 100 bunnies per acre of land in an island)
True or false:
Measuring density of population is a difficult task
True
It is used to estimate the size of a population where it is impractical to count every individual
Mark and recapture method
Briefly explain mark and recapture method
It captures a small no. of individuals, put a harmless mark on them and release them back into the population
It is the pattern of spacing among individuals within the geographic boundaries
Dispersion
What are the 3 general patterns of dispersion
Clumping
Uniform
Random
* most species live in clumps or groups
individuals in a population are clustered together, creating some patches with many individuals and some patches with no individuals
Clumped dispersion
occur when resources are concentrated in small areas within a larger habitat or because of individuals forming social groups
Clumped dispersion
Individuals of a population are spaced more or less evenly
Uniform dispersion
Uniform dispersion is a result of interactions between individuals like ____ and ____ . It occurs where individuals must compete for a _____
Competition and territory
limiting resource
Individuals are distributed randomly, without a predictable pattern
Random dispersion
Examples of random dispersion
Dandelions and other plants that have wind-dispersed seeds
It explains how fast a given population grows
Population growth rate
How does population growth rate is being measured in different ways
Microorganisms (provide direct measure)
Plants/ animals (estimate population sizes and growth rates)
What are the 2 kinds of population growth
Exponential growth
Logistic growth
“J”-shaped population growth pattern
Exponential growth
”S”-shaped population growth pattern
Logistic growth
Population growth usually stops due to ______
Lack of resources
- food
- water
- shelter
- space
True or false:
Population growth usually stops due to build up of waste products which poison the organisms
True
It is the number of organism of one species that an environment can support
Carrying capacity ( s-shaped growth)
This growth is slow at first because the no. Of reproducing organism is small
Exponential growth (j-shaped curve)
What is the strategist for
J:
S:
J: “r” strategist
S: “k” strategist
What are the living conditions and environment in
R strategist:
K strategist:
R strategist: unstable and unpredictable enviro
K strategist: more stable enviro
Which growth pattern produces more offspring
J-shaped population growth patterns (r strategist)
What are some examples in
J-shaped:
S-shaped:
J-shaped: dogs cats insects fish
S-shaped: humans lions whales
What are the 2 types of limiting factors
Density dependent factor
Density independent factors
What are the population relationships in density dependent factor
Prey-predator relationship
Competition
Disease
prey relationships often show a cycle of population increases and decreases over time
Predator
How does high density affect the environment
Crowding cause stress
= decrease in population size
What are some density-independent factors
Severe storms and flooding
Sudden unpredictable severe cold spells
Earthquake and volcanoes
Catastrophic meteorite impacts
true or false:
populations growth and speed is usually linear
false - not
briefly explain
Density dependent factors
Density independent factors
Density dependent factors:
limiting factors that bcm more intense as the population density increases (overcrowding and competition)
Density independent factors:
limiting factors that can cause popu decline or growth but impact is not directly related to hoe crowded/ sparse the population is (external enviro that affects popu regardless of its size and density)
why did the industrial revolution increase population size
due to advances in medicine, technology and cleanliness
how does industrial revolution helped in food production
by leading to an increase in pesticides and fertilizer use
true or false:
the human population increased relatively slowly until about 1600 and then began to decline slowly
false - until abt 1650 and then GROW exponentially
it is a model that states that the population will eventually stop growing when the country transitions from high birth rates and high death rates to low birth rates and death rates, stabilizing the population.
demographic transition
population change is governed by the balance between ____ and ____
birth rates and death rates
what happens if the birth rate stays the same and the death rate decreases
population numbers will grow
what happens if the birth rate increases and the death rate stays the same
population numbers will grow
most of the current global population growth is concentrated in _____ countries
developing
world’s current population growth is happening in developing countries, rather than developed nations
what is more a factor of industrialized nations, death rates or increasing birth rates
death rates (life expectancy keeps increasing )
death rate is higgh in industrilized nation
what is zero population growth
birth rate equals death rate
true or false:
It is very difficult for ecologists to calculate human carrying capacity.
true
refers to the maximum number of individuals of a particular species (in this case, humans) that the Earth’s resources can sustain indefinitely without causing irreversible damage or degradation to the environment and ecosystems
global carrying capacity
briefly explain global carrying capacity
an estimate of how many people the planet Earth can support with the available natural resources, living space, and ability to recycle waste products without depleting or destroying those resources beyond recovery
estimates involve making predictions about future trends in demography, resource availability, technological advances and economic development
carrying capacity
true or false:
the carrying capacity of Earth for humans is certain
false - uncertain
what is the average estimate of the carrying capacity of Earth for human
10-15 billion people
it is the study of human population growth characteristics
demography
what is one important demographic factor in present and future growth trends in a country
age structure
it is the relative number of individuals at each age
age structure
what is the infant mortality rate in industrialized countries and less-industrialized countries
less-industrialized countries have a greater infant mortality rate than industrialized countries
what is the life expectancy in industrialized countries and less-industrialized countries
industrialized countries has greater life expectancy than less-industrialized countries
briefly explain immigration and emigration
immigration: live in a country that is not the country of origin
emigration.: leave the country of origin and live someplace else
from year 2009 to 2020, has the Philippine population been growing or declining over these years?
growing
what is the ph population in Dec 2020, Dec 2019 and Dec 1950
109.6 million people in 2020
108.1 million people in 2019
18.6 million people in 1950
ph population data is updated _____ and available from ____ to ____
yearly
available from Dec 1950 to Dec 2020.
it is the study of how various factors impact population growth, rates of survival and reproduction, and risk of extinction
population ecology
( understand how populations fluctuate, how they respond to environmental changes, and how they interact with other species in an ecosystem )
