Organism Interactions in Ecosystems
Presentation
•
Science
•
6th - 8th Grade
•
Practice Problem
•
Medium
+5
Standards-aligned
Barbara White
Used 35+ times
FREE Resource
11 Slides • 16 Questions
1
Middle School
2
Define biotic and abiotic factors and identify examples of each in an ecosystem.
Explain how limiting factors determine the carrying capacity of a population.
Describe how competition and an organism's niche influence survival and interactions between species.
Analyze the cyclical relationship between predator and prey populations in an ecosystem.
3
Key Vocabulary
Ecosystem
A community of living organisms interacting with their non-living physical environment.
Biotic Factor
The living or once-living components of an ecosystem, such as plants and animals.
Abiotic Factor
The non-living chemical and physical parts of the environment that affect living organisms.
Limiting Factor
An environmental factor that restricts the size, growth, or distribution of a population.
Carrying Capacity
The maximum population size of a species that the environment can sustain indefinitely.
Niche
The specific role an organism plays within its ecosystem, including its diet and behavior.
4
Key Vocabulary
Competition
The struggle between organisms to use the same limited resources, such as food or space.
Interspecific Competition
Competition for the same limited resources that occurs between members of different species.
Intraspecific Competition
Competition for the same limited resources that occurs between members of the same species.
Predator
An organism that hunts and kills other organisms for its primary food source.
Prey
An organism that is hunted and killed for food by another organism.
5
What Are Ecosystems?
An ecosystem is a community of interacting organisms and their environment.
Organisms depend on living (biotic) and non-living (abiotic) factors to survive.
Ecosystems can be aquatic (water-based) or terrestrial (land-based).
6
Multiple Choice
What is the definition of an ecosystem?
A community of interacting organisms and their environment
A group of the same type of organisms
The non-living things in a certain place
A single animal or plant living alone
7
Multiple Choice
What is the relationship between the living (biotic) and non-living (abiotic) factors in an ecosystem?
Living organisms depend on non-living factors to live.
Non-living factors are created by living organisms.
Living organisms are not affected by non-living factors.
Non-living factors only exist in aquatic ecosystems.
8
Multiple Choice
A desert with lizards and cacti is a terrestrial ecosystem, while an ocean with fish and coral is an aquatic ecosystem. What must be true for both of these to be considered ecosystems?
Both contain organisms that depend on their living and non-living environment.
Both must be the same size to be considered ecosystems.
Both are land-based types of ecosystems.
Both have the same kinds of animals and plants.
9
What Are Limiting Factors?
A limiting factor is a resource that restricts how large a population can grow.
Light is needed for photosynthesis, and water is essential for all living things.
Shelter offers protection, while temperature must be within an organism's survival range.
Soil type determines which plants can grow, which in turn supports local animals.
10
Multiple Choice
Which of the following best defines a limiting factor?
A resource that helps a population grow infinitely.
A resource that only affects plants, not animals.
A resource that is always abundant in every ecosystem.
A resource that restricts how large a population can grow.
11
Multiple Choice
Why are resources like water, shelter, and a suitable temperature range considered limiting factors?
They are only needed by plants for photosynthesis.
They provide protection but do not affect population size.
They are essential for survival, and their scarcity can prevent a population from growing.
They determine the climate of an ecosystem.
12
Multiple Choice
If a region's soil type can only support a few kinds of plants, what is the most likely impact on the local animal populations?
The animal population will be unaffected by the type of plants.
The animal population will grow larger because there is less competition from plants.
The animals will adapt to eat the soil directly.
The animal population will be limited due to the restricted variety of plants.
13
Carrying Capacity and Population Growth
The limiting factors in an ecosystem determine its carrying capacity for a species.
Carrying capacity is the maximum population that available resources can support long-term.
Exponential growth (Curve A) occurs when there are no limits on the population.
Logistic growth (Curve B) slows and levels off at the carrying capacity.
14
Multiple Choice
What does the 'carrying capacity' of an environment represent?
The maximum population size that an environment can support over time.
The initial number of individuals that start a new population.
The speed at which a population increases when it has no limits.
The total area of the environment that a population lives in.
15
Multiple Choice
What causes a population to follow a logistic growth pattern instead of an exponential one?
The presence of limiting factors, such as competition for resources.
The absence of any limiting factors in the environment.
A continuous increase in the population's growth rate.
A pattern of growth represented by a steep, J-shaped curve.
16
Multiple Choice
A few deer are introduced to a large island with abundant food and no predators. Which statement best predicts the long-term growth of this deer population?
The population will grow exponentially at first, then slow down as it approaches the environment's carrying capacity.
The population will show a steady, constant rate of logistic growth from the beginning.
The population will grow exponentially forever without ever slowing down.
The population will immediately level off and stop growing.
17
Biotic Interactions: Predator and Prey
Biotic factors are the living parts of an ecosystem, like predators and prey.
Predator and prey populations directly impact one another and follow a cyclic pattern.
When more prey are available, the predator population can grow with more food.
More predators lead to fewer prey, which in turn reduces the predator population.
18
Multiple Choice
Which statement best describes the relationship between predators and prey in an ecosystem?
They are living factors whose populations directly influence one another.
They are non-living factors that have no effect on each other.
One is a living factor and the other is a non-living factor.
They are two species that cooperate to find the same food source.
19
Multiple Choice
What is the primary reason that a growing prey population can lead to an increase in the predator population?
The availability of more prey provides more food for predators.
A decrease in prey causes predators to reproduce more.
Predators and prey compete for the same resources.
Predators learn to hide from the increased number of prey.
20
Multiple Choice
If a large increase in the number of predators leads to a sharp decline in the prey population, what is the most likely long-term outcome for the predators?
The predator population will eventually decrease due to a lack of food.
The predator population will increase as they find other food sources.
The predator population will remain stable indefinitely.
The prey population will quickly recover and grow larger than before.
21
Interspecific Competition
Competition between different species for the same limited resources is called interspecific competition.
For instance, giraffes eat leaves high on trees, while zebras eat lower leaves and grasses.
Each species occupies a specific niche, which helps them avoid direct competition with others.
Intraspecific Competition
Competition that happens among members of the same species is called intraspecific competition.
For example, male giraffes feed with their heads up while female giraffes feed down.
Many animals also reduce competition by claiming and defending their own territories.
22
Multiple Choice
What is the main difference between interspecific and intraspecific competition?
The types of species involved in the competition.
The kind of resources being competed for.
The time of day that the competition occurs.
The environment where the competition takes place.
23
Multiple Choice
What is the main purpose of a species occupying a specific niche or an animal defending a territory?
To attract more mates from different species.
To increase the total amount of food available.
To reduce competition for the same limited resources.
To make it easier to move between different habitats.
24
Multiple Choice
If a drought caused all the lower leaves on trees to wither, leaving only leaves high up, what would be the most likely consequence for the giraffe population described?
Interspecific competition between giraffes and zebras would decrease.
Intraspecific competition between male and female giraffes would increase.
Male and female giraffes would cooperate to find new food sources.
Zebras would begin competing with giraffes for the high leaves.
25
Misconception | Correction |
|---|---|
Ecosystems are only large areas like forests or deserts. | Ecosystems can be any size, from a large ocean to a small puddle. |
Competition always results in a clear winner and a loser. | Often, both competing populations survive, but with reduced numbers. |
An organism's niche is another word for its habitat. | A niche describes an organism's total role, including diet and behavior. |
A population will always grow until it runs out of space. | Growth is limited by factors like food, water, and predators. |
26
Ecosystems are communities where organisms interact with biotic and abiotic factors.
A population's growth is restricted by limiting factors, determining carrying capacity.
The relationship between predator and prey populations often follows a predictable cycle.
Competition for resources occurs both within and between different species.
An organism's unique role, or niche, helps to reduce the intensity of competition.
Organisms reduce competition by partitioning resources or defending territories.
27
Poll
On a scale of 1-4, how confident are you about the concepts covered in today's review?
1
2
3
4
Middle School
Show answer
Auto Play
Slide 1 / 27
SLIDE
Similar Resources on Wayground
21 questions
Solar System 2
Presentation
•
6th - 8th Grade
21 questions
SC.8.E.5.9 - Eclipses Lesson
Presentation
•
6th - 8th Grade
20 questions
Bridge Types
Presentation
•
6th - 8th Grade
20 questions
Natural Resources
Presentation
•
6th - 8th Grade
20 questions
States of Matter Review
Presentation
•
3rd Grade
21 questions
Space Tools
Presentation
•
6th - 8th Grade
21 questions
Symbiosis
Presentation
•
6th - 8th Grade
21 questions
PWMS Classification
Presentation
•
6th - 8th Grade
Popular Resources on Wayground
10 questions
Safety Day 2026 – Student Review
Quiz
•
9th Grade
21 questions
Continents and Oceans
Quiz
•
6th Grade
20 questions
Parts of Speech
Quiz
•
5th Grade
16 questions
Subject & Predicate
Quiz
•
5th Grade
25 questions
Multiplication Facts
Quiz
•
5th Grade
12 questions
Map Skills
Quiz
•
3rd Grade
22 questions
Continents and Oceans
Quiz
•
5th Grade
15 questions
Rounding Decimals
Quiz
•
5th Grade
Discover more resources for Science
20 questions
Newton's Laws of Motion
Quiz
•
8th Grade
20 questions
Elements, compounds, and mixtures
Quiz
•
6th Grade
10 questions
6.6D - Relative Density Review
Quiz
•
6th Grade
15 questions
potential and kinetic energy
Quiz
•
8th Grade
21 questions
Newton's Laws of Motion
Quiz
•
8th Grade
20 questions
Elements, Compounds and Mixtures
Quiz
•
8th Grade
10 questions
Exploring Chemical and Physical Changes
Interactive video
•
6th - 10th Grade
20 questions
CONDUCTION,CONVECTION AND RADIATION
Quiz
•
6th Grade