Chapter 1: Ecology, Evolution, and the Scientific Method Flashcards
______________ is the scientific study of the abundance and distribution of organisms in relation to other organisms and environmental conditions
Ecology
_____________ is the study of change, interactions, and flows of matter and energy.
Ecology
____________ __________ are biological entities that have their own internal processes and interact with their external surroundings
Ecological systems
Ecology is a system with ____________ and __________ components.
Biotic
Abiotic
From smallest to largest, what are the systems of ecology?
Individual
Population
Community
Ecosystem
Biosphere
Biology, including ecological systems, operates at a variety of scales. Each ecological system is made up of systems of the next size down, all interacting. Each system has characteristics—___________ __________—that its components do not have
Emergent properties
An _____________ is a living being, the most fundamental unit of ecology
Individual
What must an individual possess?
A membrane or other covering across which it exchanges energy and materials with its environment
What is a species?
Histocially defined as a group of organisms that naturally interbreed with each other and produce fertile offspring; current research demonstrates that no single definition can be applied to all organisms (e.g., some species of salamanders only produce daughter clones; prokaryotic organisms routinely undergo horizontal gene transfer)
A _______________ consists of individuals of the same species living in a particular area
Population
What five distinct properties are exhibited by populations but not individuals?
- Geographic range
- Abundance
- Density
- Change in size
- Composition
The ___________ _________ of a population, also known as its distribution, is the extent of land or water within which a population lives.
Geographic range
The _______________ of a population refers to the total number of individuals
Abundance
The ____________ of a population refers to the number of individuals per unit of area
Density
The ___________ ___________ of a population refers to increases and decreases in the number of individuals in an area
Change in size
What does the composition of a population mean?
Composition describes the makeup of the population in terms of gender, age, or genetics
What is a community?
A level of ecological organization that includes all populations of species living together in a particular area
An _____________ is composed of one or more communities of living organisms interacting with their nonliving physical and chemical environments, which include water, air, temperature, sublight, and nutrients
Ecosystem
What are usually the areas of focus at the level of ecosystems?
The movement of energy and matter between physical and biological components of the ecosystem
____________ states that matter cannot be created or destroyed but only change form
Law of conservation of matter
____________ states that energy cannot be created or destroyed but can be converted into different forms
The law of conservation of energy or the first law of thermodynamics
What occurs when energy changes forms?
Heat
____________ flows through an ecosystem; ____________ cycles within an ecosystem
Energy
Matter
What is the highest level of ecological hierarchy?
Biosphere
What is a biosphere?
The level of ecological organization that includes all eocsystems on Earth
All transformations of the biosphere are internal, with two exceptions. What are they?
- The energy that enters from the Sun
- The energy that is lost to space
A ____________ __________ _________ occurs when the gains and losses of ecological systems are in balance
Dynamic steady state
________________ is an attribute of an organism, such as its behavior, morphology, or physiology
Phenotype
____________ is the set of genes an organism carries
Genotype
___________ refers to change in the genetic composition of a population over time or, more specifically, changes in the frequency of genotypes in a population
Evolution
What is genetric drift?
Evolution that occurs to random events over time
___________ __________ describes the reproduction of phenotypes such that those best suited to the environment survive and those less fit are eliminated
Natural selection
Do the forces of natural selection act on phenotype, genotype, or both?
Phenotype
Natural selection acts on “only what it can see”
Is natural selection random or nonrandom?
Nonrandom
It is a nonrandom change in allele frequency in a population
What is fitness?
The survival and reproduction of an individual
What three conditions must be met for evolution to occur, according to Charles Darwin?
- Individuals vary in their traits
- Parental traits are inherited by their offspring
- The variation in traits causes some individuals to experience higher fitness, the survival and reproduction of an individual
A _______________ displays phylogenetic relationships
Cladogram
What is a producer? Also known as an autotroph?
An organism that uses photosynthesis to convert solar energy into organic compounds or uses chemosynthesis to convert chemical energy into organic compounds
What is a consumer? Also known as a heterotroph?
An organism that obtains its energy from other organisms
What is a mixotroph?
An organism that obtains its energy from more than one source
______________ is an organism that kills and partially or entirely consumes another individual
Predator
______________ represent a special kind of predator that lay their eggs on or inside other animals, which eventually hatch into largvae that consume the host from the inside
Parasitoids
There are four types of consumers? What are they?
- Predator
- Parasitoid
- Parasite
- Herbivore
What is a parasite?
An organism that lives in or on another organism, while rarely killing their hosts
______________ is a parasite that causes disease in its host
A pathogen
A _____________ is an organism that consumes producers such as plants and algae
Herbivore
_____________ is an interaction resulting in negative effects between two species that depend on the same limiting resource to survive, grow, and reproduce
Competition
What is mutualism?
An interaction between two species in which each species receives benefits from the other
What is commensalism?
An interaction in which two species live in close association and one species receives a benefit, while the other experiences neither a benefit nor a cost
What is a symbiotic relationship?
When two different types of organisms live in a close physical relationship
Are all symbiotic relationships positive?
No, symbiotic relationships include forms of parasitism and parasitoidism
What two organisms make up a licen?
A fungus and a green algae or cyanobacteria
What does the fungus provide in the lichen symbiosis? The algae or cyanobacteria?
The fungus provides nutrients; the algae provides carbohydrates from photosynthesis
A ________________ is an organism that consumes dead animals
Scavenger
What is a detritivore?
An organism that feeds on dead organic matter and waste products that are collectively known as detritus
What is a decomposer?
Organisms that break down dead organic material into simpler elements and compounds that can be recycled through the ecosystem
A __________ is the place, or physical setting, in which an organism lives
Habitat
What is a niche?
The range of abiotic and biotic conditions an organism can tolerate.
Can two species have the same niche?
No two species have the same niche because each has unique phenotypes that determine the conditions it can tolerate
_______________ are ideas that potentially explain a repeated observation
Hypotheses
What is a proximate hypothesis?
A hypothesis that addresses the immediate changes in an organism’s hormones, physiology, nervous system, or muscular system
_______________ are statements that arise logically from hypotheses
Predictions
What is an ultimate hypothesis?
A hypothesis that addresses why an organism has evolved to respond in a certain way to its environment in terms of the fitness costs and benefits of the response
In a ____________ ____________ a hypothesis is tested by altering a factor hypothesized to be the cause of a phenomenom
Manipulative experiment
What do we mean by “treatment”?
The factor we want to manipulate
What is a control?
The treatment that includes all aspects of an experiment except the factor of interest
What do we mean by replication?
Being able to produce a similar outcome multiple times
What is randomization?
An aspect of experiment design in which every experimental unit has an equal chance of being assigned to a particular manipulation
_____________ is a simplified ecological system that attempts to replicate the essential features of an ecological system in a laboratory or field setting
Microcosm
______________ ___________ is an approach to hypothesis testing that relies on natural variation in the environment
Natural experiment
__________ _________ is a representation of a system with a set of equations that correspond to hypothesized relationships among the system’s components
Mathematical model
