Chapter 3: The Biosphere What is ecology? Ecology study of interactions among organisms, between organisms, and their environment
Life depends on other living things and natural resources (air, water, land) Levels of Organization 1. Species living thing
Levels of Organization 2. Population of of individuals species in an area.
Levels of Organization 3. Community that live together in an area. Several populations interacting together. Levels of Organization 4. Ecosystem Collection of all
organisms ( ) in a particular place together with the (physical) environment.
Levels of Organization 5. Biomes of with similar climate and communities.
Levels of Organization 6. Biosphere The highest level of organization. The portion of the that supports life.
Levels of Organization Biotic and Abiotic Factors Biotic Plants, Animals ,Mold, Fungi, Bacteria, Protist Abiotic
Sunlight, soil, wind, water, temperature Ecological Methods 1. 1st step to designing an experiment 2.
test hypotheses 3. make models based on observation & experiment Helps make future predictions 3.1 Review
1. Many populations together is called a 2. Combination of biotic and abiotic factors in an environment make up the 3. Whats the different between biotic and abiotic? 3.2 ENERGY FLOW (Autotrophs and Heterotrophs) One of the most important factors
to determine capacity to sustain life is Energy Flow Autotrophs ( ) Trap light energy to produce food Plants Some protists
Some bacteria Converts light into chemical energy 6CO2 + 6H2O SUN C6H12O6 + 6O2
Converts chemical energy into carbohydrates Heterotrophs ( Must acquire energy from other organisms Herbivores Carnivores animals
both eat dead plants & animals Decomposers break down organic matter )
3.2 Review 1. Another name for autotroph is 2. What are the two processes autotrophs use to make energy? 3. What are the four types of vores? 3.3 Energy Flow in
Ecosystems Food Chains and Food Webs Food Chains and Food Webs SUN Autotrophs Heterotroph 1. Food
shows energy transfer 2. Food shows possibilities of energy transfer Trophic Levels Trophic Levels
in a food chain/web T Level 2 T Level 1 Ecological Pyramids Ecological Pyramids shows relative amount of energy at each level ( )
total amount of living tissue within a trophic level 3.3 Review 1. Which is more complex food chain or web? 2. Grass rabbit fox alligator Which is T2? 3. What is biomass?
4.2 Niches and Community Interactions Tolerance Species ability to survive and reproduce under a of environmental .
Intolerance Zone Habitat General place an organism Determined by species . .
Niche of physical and biological in which a species lives and the the species what it needs to survive and reproduce. Niches
Things needed for Plants- sunlight, water and soil nutrients Animals- nesting, space, shelter, food, places to feed resources
required for survival. factors Ex- amphibians lose and absorb water through skin::must live in moist places.
resources required for survival. factors E.g. when/how reproduces, food, way obtains food. Competition Different organisms attempting to use
resources. resources at time and place = specific competition-same species competing specific competition- different species competing
What do you think these two males are fighting over? Competitive Exclusion Principle - two species can occupy exactly the
at the same time. -One species will win and survive. -One will lose and die. Dividing Resources Helps determine the and
of species in a community and the niche each species occupies. Predation, Herbivory, and Keystone Species Predation
Where one animal (the ) captures and feeds on another animal (the ) Predation Predators affect
of population and determine the places prey can . E.g. birds can play important role in regulating mouse population sizes Herbivores Herbivory - Animal (herbivore) feeds on
(plants) Affect and of . E.g- Many white-tailed deer are eliminating their favorite food plants across US.
Keystone Species A species that can change in a community Ex- Sea otters eat large amounts of sea urchins, which eat kelp.
Sea otters almost by hunting; urchins population ; ate all the kelp. Other organisms also . Symbioses Any relationship in which species live
together Three main classes: 1.Mutualism 2.Parasitism 3.Commensalism Mutualism Relationship in which
species E.g. Sea anemone and clownfish Sea anemone-offers shelter; clownfish protects for preditors. Parasitism Relationship where one organism lives
another organisms and . Commensalism Relationship where organism and the is harmed or helped
_ 4.2 Review 1. What could be a physical and biological resource for a flower? 2. When does competition occur? 3. Ants protecting a tree that gives the ants shelter is an example of
Chapter 5 Populations 5-1 How Populations Grow How Populations Grow Characteristics of Populations
4 important characteristics of a population Geographic Growth structure Geographic Distribution
Geographic distribution by a population. Ranges can vary enormously in Population Density Population Density - number of individuals .
This picture shows the population density of people. Populations Growth Three factors affect population size: number of number of number of individuals that the population.
* Simply put, a population will increase or decrease in size depending on how many individuals are added to it or removed from it Immigration & Emigration movement of individuals an area causes growth.
movement of individuals of an area causes decrease. Age Structure of males and females of a population contains. Age structure greatly effects reproduction
Exponential Growth Exponential growth When the generation is than the generation . Population size will increase if there is abundant
and , and protected from predators and disease Under ideal conditions with unlimited . Logistic Growth Logistic growth- occurs when growth
following a period of exponential growth. As , the growth of a population slows or stops. The general, S-shaped curve of this growth pattern, is called
growth. Carrying Capacity number of individuals of a particular species that a given environment can .
Review 5.1 1. List the four characteristics of population. 2. What factors can change a population's size? 3. What is carrying capacity?
5.2 Limits to Growth factor factor that controls the of a population. Density dependent Density independent Limiting factors the capacity of an
environment for a species. Density- Dependent Factors Limit size when the individuals reach a certain 1.
for food, water, space, sunlight, etc. 2. Predation and populations cycle up and down of Wolf/Moose graph
Moose Wolves Density- Dependent Factors Continued 3. the
the population, the easier it spreads 4. from overcrowding can lower birth rates, higher death rates, can cause parents to neglect young, lead to emigration Density -Independent
Factors Affect all populations and density Weather, , seasonal change, human interventions (dams, logging, housing developments)
Review 5.2 1. What are the two types of limiting factors? 2. What are the four density-dependent factors? 3. Define density-independent factors.
5.3 - Historical Overview For most of human existence, the population grew slowly because life was harsh. Food was hard to find. Predators and diseases were common and life-threatening. Historical Overview
Limiting factors kept human death rates Until fairly recently, only the children in the world to adulthood. Because death rates were so high, families had children, just to make sure that
would survive. . Exponential Human Population Growth As civilization life became began to
, , and the human population more rapidly. What types of things made life easier? The Predictions of Malthus Exponential growth
continue Two centuries ago, English economist Thomas Malthus suggested that only , and disease could limit human population growth. Malthuss work was vitally important to the thinking of Charles .
The Demographic Transition Three stages Stage I, birthrates and death for most of history. are
The Demographic Transition In Stage II, advances in nutrition, sanitation, and medicine lead to . Birthrates remain Births exceed deaths Population
exponentially. The Demographic Transition During Stage III, as and living standards , families have fewer children; population growth
. When the birthrate death rate, growth stops. The Demographic Transition So far, the United States, Japan, and Europe have the demographic transition. Parts of South America, Africa, and Asia are passing
through . A large part of ongoing human population growth is happening in only ten countries, with in the lead. Review 5.3 1. What are three things Malthus suggested would decrease population
size? 2. Which demographic stage has advances that result in higher birthrates and lower death rates? 3. In Stage III, why would families have fewer children?
