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Number of items: 124
Date joined: Apr 05 2016

Jon Darkow has taught a variety of science and science education courses at the high school and coll ...Read more Jon Darkow has taught a variety of science and science education courses at the high school and college level for the past 20 years. Currently, Jon teaches AP Physics, College Anatomy and Physiology I and II, and high school Biology at Marion L Steele High School in Amherst, Ohio. Jon is most interested in teaching scientific reasoning and systems thinking using system dynamics modeling. Hide full description


Jon Darkow's Work

#1

Transformation Simulation

Simulation allows students to test the transformation principle. Two major goals of the experiment a ... Read more
Simulation allows students to test the transformation principle. Two major goals of the experiment are: 1. Allow users to see that supernatant from heat-killed bacteria can transform the genes of another bacterium. 2. What transforms the inheritance of the bacteria is DNA, not RNA or proteins.
sim136167 runs
transformation DNA biology
#2

Position, Velocity, and Acceleration Simulation

sim3360 runs
Science
#3

Tesing Unknown Enzymes

sim289318 runs
enzymes
#4

Logistic Growth Model and the Butterfly Effect

Model allows users to test the starting population size (N), the carrying capacity of the populatio ... Read more
Model allows users to test the starting population size (N), the carrying capacity of the population (K), and the intrinsic rate of growth (r max). Iterations are discrete, not continuous.
sim6273 runs
logistic growth carrying capacity
#5

Evolution of Antibiotic Resistance Simulation

Evolution of Antibiotic Resistance Simulation. This model tracks the accumulation of 40 colonies of ... Read more
Evolution of Antibiotic Resistance Simulation. This model tracks the accumulation of 40 colonies of bacteria. The main purpose of the model is to show that new adaptations are not caused by an environmental factor, like antibiotics. Rather, new adaptations are the selection of available variations. In this model you can increase variations by increasing the UV dose. The UV dose increases the mutation rate with a Monte Carlo function.
sim195896 runs
Biology Science Ecology Education
#6

Cell Cycle - Simpler 2020

sim61862 runs
Biology Science Education
#7

Apterous Genetics

Apterous is an allele that results in a fly without wings. Wild-type variants have normally function ... Read more
Apterous is an allele that results in a fly without wings. Wild-type variants have normally functioning wings. The goal of this simulation is to determine the pattern of inheritance for the apterous phenotype. Is apterous dominant or recessive? Sex-linked or autosomal? Complete, incomplete, or codominant?
sim309736 runs
Genetics
#8

Enzyme Diversity: Enzymes, Products, and Substrates

sim1144485 runs
enzymes substrates products DNA trypsin
#9

Water Potential and Osmosis

Factors that affect the flow across a semi-permeable membrane.
sim410060 runs
#10

Slider Bets and Metacognition

sim89 runs
Education
#11

Stock, Inflow, and Outflow with Atrazine

Simple stock and flow diagram. Flows linear.
sim92 runs
stock flow atrazine
#12

Neurophysiology and Information Processing 2022

sim20496 runs
Biology information processing neuron neurotransmission neurophysiology
#13

Extinction

sim
#14

Evolving Bits N=40

sim2790 runs
evolution bits receptor substrate
#15

Genotyping with Electrophoresis

sim44375 runs
biology inheritance DNA restriction enzyme
#16

Chaos Theory: Strange Attractor

Manipulate the main variables of the Lorenz equation.
sim2463 runs
chaos theory Lorenz attractor manifold
#17

ATP Hydrolysis

sim7070 runs
Science ATP Free Energy Entropy
#18

Photosynthesis Simulation with Variance

sim209064 runs
#19

Photosynthesis Simulation - Simplified

sim85 runs
Environment Biology Science Ecology Education
#20

Evolving Bits

Diversity and selection for the basis of evolution. This simple model tries to illustrate these conc ... Read more
Diversity and selection for the basis of evolution. This simple model tries to illustrate these concepts.
sim1676 runs
Diversity Selection Evolution Receptor Antigen
#21

Photosynthesis Model

sim2603375 runs
#22

Carbon in the Atmosphere - Graphic Input constant

sim28 runs
#23

Illusions and Assumptions

sim977 runs
Biology Science
#24

Thyroid Hormone - Negative Feedback

sim81341 runs
negative feedback thyroid hormone metabolism biology
#25

Ball Bet Code Generators for Answer Keys

sim843 runs
Education
#26

Predator Prey Model - Mobile

sim132 runs
Biology
#27

Gravitational Attraction of Three Bodies

sim423 runs
Science Education Forces Gravitation Physics
#28

Mechanical Energy and Kinematics

sim462 runs
Science Physics Energy Acceleration Velocity
#29

Phosphorus in Lake: Changes to Flows in a Dynamic System

This model allows users to experiment with a very simple dynamic system: one stock (Phosphorus in a ... Read more
This model allows users to experiment with a very simple dynamic system: one stock (Phosphorus in a lake), an inflow (added P/day), and an outflow (removed P/day). The flows can either be constant throughout the simulation run, or dynamic (changing throughout the simulation run.)
sim3348 runs
flows dynamic phosphorus
#30

HPV with Influenza A Humoral Immunity

Immune response of HPV
sim28483 runs
HPV antibodies biology Immunity
#31

Diffusion of a Spherical Cell

Why are cells small? This model allows users to see how the size of a sphere affects the rate of dif ... Read more
Why are cells small? This model allows users to see how the size of a sphere affects the rate of diffusion.
sim147238 runs
diffusion surface area volume radius
#32

Population dynamics of white footed mouse

sim1498299 runs
#33

Catastrophic Regime Change in Aquatic Ecosystems

sim116129 runs
Ecology
#34

Grant Finches Mobile

sim15 runs
#35

Student Model (X. Hicks and J. Margraf) - HIV

sim84 runs
#36

Oxytocin-P

sim36 runs
Biology
#37

Ball Bet 3.0.2

sim2 runs
#38

Exponential Growth

sim13757 runs
Biology Ecology
#39

Circadian Clock in the Mouse

Transcriptional Translational Feedback Loop in the Mouse
sim31368 runs
Mouse Circadian Clock
#40

Beta Cell Membrane Transport - Insulin Regulation

sim269 runs
Insulin Glucose Beta Cell
#41

Limiting Nutrients in Aquatic Ecosystems

Experiment with a variety of nutrients that are limited by different degrees in four different ecosy ... Read more
Experiment with a variety of nutrients that are limited by different degrees in four different ecosystems.
sim132664 runs
limiting nutrients ecosystem biology logistic growth
#42

Understanding Linear Motion

Understand linear motion with automated feedback.
sim1339 runs
Science Education physics motion velocity
#43

System Dynamics of Carbon Budget

Simulation of the system dynamics of the global carbon dioxide budget based on the work on systems d ... Read more
Simulation of the system dynamics of the global carbon dioxide budget based on the work on systems dynamics based on John Sternman (MIT) and Krytyna Stave (University of Nebraska)
sim16646 runs
system dynamics carbon climate
#44

Evolution of LAP Allele in Mussels

sim85766 runs
Evolution Natural Selection Cline
#45

Beta Cell Simulation - Split story

sim81873 runs
#46

Cell Cycle Simulation

sim2559 runs
Biology
#47

Fruit Fly with variable sample size

sim43 runs
#48

Soybean and Aphid Dynamics

sim141 runs
Environment Biology Science Economics Ecology
#49

Tryptophan Operon: A repressible system

sim89417 runs
#50

Steady State in Freshwater Ecosystems

sim35133 runs
#51

Body Temperature Regulation with Scatter Plot

sim196 runs
Biology Science Education Health
#52

HPV and Adaptive Immune Response

sim12570 runs
HPV Antibodies feedback loops vaccine
#53

Uniform Circular Motion

sim850 runs
Science Education Circular Motion Physics
#54

Guppy Evolution

sim187975 runs
evolution biology genes
#55

Pattern with recessive single band

sim95462 runs
genetics
#56

Cellular Respiration Accounting Model

The purpose of the model is to understand how glucose is metabolized, and how the energy stored in i ... Read more
The purpose of the model is to understand how glucose is metabolized, and how the energy stored in its chemical bonds is transfered.
sim736445 runs
cellular respiration aerobic respiration ATP biology
#57

Lactose Operon: An Inducible System

In this simulation users explore the negative feedback system of the Lactose Operon found in bacteri ... Read more
In this simulation users explore the negative feedback system of the Lactose Operon found in bacteria. Lactose induces the system by inhibiting and inhibitor.
sim147170 runs
Inhibition negative feedback biology lactose operon
#58

Ball Bet for Metacognition - Random

sim105 runs
Education
#59

GLUT and Insulin

sim20 runs
#60

Oxytocin and Child Birth

sim245580 runs
#61

Evolution: Grants Finches

Models the effects on population sizes of ground finches with different beak sizes in response to di ... Read more
Models the effects on population sizes of ground finches with different beak sizes in response to different amounts of annual precipitation.
sim12588 runs
evolution biology natural selection
#62

The dynamics of photosynthesis - variable sample size

The dynamics of photosynthesis - variable sample size
sim94825 runs
photosynthesis sample size biology
#63

Evolution and Natural Selection

sim366980 runs
#64

Transformation Experiment with Controls

Simulation allows users to test the bacterial transformation principle discovered by Frederick Griff ... Read more
Simulation allows users to test the bacterial transformation principle discovered by Frederick Griffith.
sim30759 runs
Biology Science Education transformation DNA
#65

Lactase with Variable Sample Sizes

Arrayed Lactase Model
sim864026 runs
Lactase array sample size biology
#66

SIR COVID-19 Coronavirus Simulation

sim19640 runs
Environment Biology Science Education SIR
#67

Photosynthesis with Variable Sample Sizes

Sample sizes of Photosynthesis stocks in an array
sim192345 runs, 152 downloads
Download Model
#68

Cardiovascular Model

sim28718 runs
#69

Simple Genetics

sim133378 runs
#70

Tick Tock: The Biological Clock and Circadian Rhythm

Explore gene expression of the transcriptional-translational feedback loop (TTFL) of the mouse circa ... Read more
Explore gene expression of the transcriptional-translational feedback loop (TTFL) of the mouse circadian rhythm.
sim1128 runs
circadian clock feedback loop
#71

Fruit Fly Choice

Simulation to model random behavior in a fruit fly choice chamber
sim1023 runs
randomness random
#72

Recombination and Gene Linkage

sim150298 runs
#73

Evolution with Heterozygous Advantage

Evolution of Populations: Genetic Drift, Natural Selection, and Mutations
sim7697 runs
evolution natural selection genetic drift
#74

White-Eyed Genetics

White-eyed is an allele that results in a fly white eyes. Wild-type variants have red eyes. The ... Read more
White-eyed is an allele that results in a fly white eyes. Wild-type variants have red eyes. The goal of this simulation is to determine the pattern of inheritance for the white-eyed phenotype. Is yellow body dominant or recessive? Sex-linked or autosomal? Complete, incomplete, or codominant?
sim191587 runs
Genetics
#75

Growth Factors, Cyclins, and Cancer

Explores the feedback loops that regulate the cell cycle. Model focuses on manipulating stimuli (gro ... Read more
Explores the feedback loops that regulate the cell cycle. Model focuses on manipulating stimuli (growth factors), to stimulate the cell cycle feedback loops.
sim310747 runs
growth factors cyclins cell cycle cancer
#76

Lactase Enzyme Simulation with Data Analysis

sim12472740 runs
#77

Lac Operon with Monod Bump

sim206354 runs
Lac Operon Gene Regulation mRNA
#78

Lotka-Volterra Predator-Prey Model

Explore my favorite aspect of system dynamics and a historic example. The homeostasis generated by t ... Read more
Explore my favorite aspect of system dynamics and a historic example. The homeostasis generated by the interconnections of a negative feedback loop governs much of life.
sim293979 runs
negative feedback loop Lotka-Volterra homeostasis predator-prey
#79

Extinction Vortex

sim66490 runs
#80

Soybean and Aphid Population Dynamics

sim2797 runs
Biology Science
#81

Information Processing and Neurophysiology Model

The main dependent variable measured in the model is the membrane potential (millivolts) of two diff ... Read more
The main dependent variable measured in the model is the membrane potential (millivolts) of two different neurons in a series. You will be able to add excitatory and inhibitory neurotransmitters, and compare how these modulate electrical impulses of the two neurons. Additionally, you will be able to compare the effects of three neurotoxins: Tetrodotoxin, botulinum toxin, and sarin nerve gas. While extremely lethal, these toxins are very instructive in understanding neurons because of the specific way the toxins act. Each toxin modifies or inhibits a specific molecule in neurons that help process and transmit information.
sim348606 runs
infromation processing neurophysiology biology
#82

Bathtub Dynamics

This simulation has three models. Model1 shows constant inflow and outflow into a bathtub. Model ... Read more
This simulation has three models. Model1 shows constant inflow and outflow into a bathtub. Model 2 shows constant inflow and nonlinear outflow based on the quantity of water in the bathtub. Model 3 shows constant inflow and nonlinear outflow based on the quantity of water in the bathtub. However, Model 3 uses Torricelli's law to calculate the flow rate based on physical principles. This law was formulated by Evangelista Torricelli, an Italian physicist, in the 17th century. It's an important principle in fluid dynamics and is closely related to Bernoulli's principle. Torricelli's law states that the speed (velocity) of efflux of a fluid through a hole under the force of gravity is proportional to the square root of the vertical distance (height) between the fluid surface and the center of the hole. The formula is given by efflux velocity = 2*g*ℎ​, where: g is the acceleration due to gravity (approximately 9.81 m/s² on Earth). ℎ is the height of the fluid column above the hole. The idea is that the fluid's potential energy due to its height is converted into kinetic energy as it falls. The higher the fluid, the greater its potential energy and thus the greater the speed at which it exits the hole. This principle is used in various applications, such as determining the flow rate of liquids from tanks, in hydrodynamics studies, and even in everyday situations like draining a bathtub. The law assumes an ideal fluid (incompressible and non-viscous) and neglects factors like air resistance and the viscosity of the fluid. It also assumes that the size of the hole is small compared to the depth of the fluid. The flow rate (the volume of fluid flowing per unit time) can be calculated by multiplying the cross-sectional area of the hole (A) by the velocity of the fluid (v), leading to the formula Q=A*v, where Q is the flow rate.
sim1812 runs
Environment Science Education Bathtub hydrodynamics
#83

Neurophysiology and Neurotoxicity

The main dependent variable measured in the model is the membrane potential (millivolts) of a motor ... Read more
The main dependent variable measured in the model is the membrane potential (millivolts) of a motor neuron and the muscle fiber it innervates. You will be able to add excitatory and inhibitory neurotransmitters, and compare how neurotransmitters modulate the electrical impulses of the motor neuron and the muscle fiber. Additionally, you will be able to compare the effects of four neurotoxins: Tetrodotoxin, botulinum toxin, sarin nerve gas, and VX. While extremely lethal, these toxins are very instructive in understanding neurons because of the specific way the toxins act. Each toxin modifies or inhibits a specific molecule in neurons that help process and transmit information.
sim46458 runs
Neurophysiology toxins sarin VX TTX
#84

Enzyme Diversity

sim484645 runs
enzyme biology substrate pepsin indicators
#85

Cellular Respiration Inquiry

Model of the dynamics of the metabolism of one mole of glucose. Randomness is built into the computa ... Read more
Model of the dynamics of the metabolism of one mole of glucose. Randomness is built into the computations.
sim114793 runs
metabolism respriation ATP biology
#86

Phenology of the Karner Blue Butterfly

Karner Blue butterfly is an endangered species. Habitat loss and climate change are contributing fac ... Read more
Karner Blue butterfly is an endangered species. Habitat loss and climate change are contributing factors to the reduction in the butterflies' population sizes. Climate change can alter the timing of lifecycles. When climate change disproportionally affects the timing of life cycles of species in an ecosystem asynchrony within a food web occurs.
sim12992 runs
asynchrony timing phenology climate change butterfly
#87

Carbon Cycle Simulation

Simulation tracks the movement of carbon to and from the atmosphere in Gt C (and Gt CO2). Users can ... Read more
Simulation tracks the movement of carbon to and from the atmosphere in Gt C (and Gt CO2). Users can manipulate with graphical inputs the changes in fossil fuel emissions, land-use, and ocean sinks.
sim11240 runs
Environment Biology Science Ecology Education
#88

Pendulum Model

sim50 runs
Science Education Physics Simple Harmonic Motion Pendulum
#89

Stock and Flow Teaching

model907 downloads
Download Model
Education
#90

Comparing COVID-19 with xxx

This model was copied from Jon Darkow:
model909 downloads
Download Model
Environment Biology Education
#91

SIR Model for Coronavirus (COVID-19)

model2118 downloads
Download Model
Environment Biology Education
#92

Epinephrine Signal Transduction

model1380 downloads
Download Model
Biology Science Education
#93

Signal Transduction Example

model790 downloads
Download Model
Biology Science
#94

Pop Growth with Resources v2

model842 downloads
Download Model
#95

Pop Growth v2

model814 downloads
Download Model
#96

Pop Growth v3

model894 downloads
Download Model
#97

Cardiac Myocytes

model1300 downloads
Download Model
Biology Education
#98

TSH-TH Feedback

model834 downloads
Download Model
Biology
#99

Hormone Sample 1

model863 downloads
Download Model
#100

Logistic Growth Model

model1295 downloads
Download Model
#101

OT Feedback

model902 downloads
Download Model
Biology
#102

Force and Position

model677 downloads
Download Model
Science physics
#103

CR and ATP coupled reaction

model858 downloads
Download Model
Biology
#104

Model1

model569 downloads
Download Model
#105

Projectile Motion Physics

model156 downloads
Download Model
Science Education physics science position
#106

Something

model664 downloads
Download Model
#107

Differential Reproduction, Natural Selection Model

This is the fourth model in a sequence of models to show the logic of natural selection, formalized ... Read more
This is the fourth model in a sequence of models to show the logic of natural selection, formalized by Earnst Mayr. Mayr E. The growth of biological thought. Cambridge: Harvard University Press; 1982.
model947 downloads
Download Model
Biology Science Education natural selection evolution
#108

Modeling Constant Acceleration

model850 downloads
Download Model
Science Education Physics Acceleration Velocity
#109

Endocrine System Dynamics

This model shows how FSH regulates the reproductive cycle in females, and how diseases may emerge fr ... Read more
This model shows how FSH regulates the reproductive cycle in females, and how diseases may emerge from underproduction and excess production of the hormone. This model was developed for a high school Anatomy and Physiology class.
model868 downloads
Download Model
Biology Physiology Feedback
#110

Two Variations - Population Growth

model905 downloads
Download Model
Biology Science Ecology Education
#111

p53 and Cell Cycle

model936 downloads
Download Model
Biology
#112

SIR Model for Coronavirus (COVID-19) - with social distancing

This model was copied from Jon Darkow:
model1223 downloads
Download Model
Environment Biology Education
#113

insulin secretion

model856 downloads
Download Model
Biology
#114

Natural Selection Model v1

model949 downloads
Download Model
Biology
#115

Mechanical Energy Model

model727 downloads
Download Model
Science Physics Acceleration Velocity Potential Energy
#116

SIR Model for COVID-19

This model was copied from Jon Darkow: This model was copied from Jon Darkow:
model832 downloads
Download Model
Environment Biology Education
#117

Exponential Growth in Population - AF

Chapter 2: Modeling the Environment
model1200 downloads
Download Model
#118

Chapter 2: Population Growth

Chapter 2 introduction
model1133 downloads
Download Model
#119

Cellular Respriation: ID process flows

model815 downloads
Download Model
#120

Limiting Nutrients Model

model988 downloads
Download Model
Environment Ecology Education
#121

Cellular Respiration Matter

model911 downloads
Download Model
#122

model1-mrd

model611 downloads
Download Model
#123

CLD Example

diagram945 downloads
Download Model
Biology
X

Uploading a Bundle from Zip

Instead of creating bundles, categories, and assemblies one by one, you can upload a single zip file that contains all of your bundle's content. To create your zipped bundle, make a folder with your bundle's name and add subfolders with your categories' names. The folder tree should have the same structure that you want the categories to have in your bundle. Place your assembly .stmx files in the appropriate category folders, then zip your bundle folder and upload it using the Upload Bundle from Zip link above.

Assemblies, Bundles, and Categories

Assemblies are self contained models that demonstrate common ways to connect together building blocks and that can be used as parts of other models. This is analogous to using prefabricated wall and roof pieces to construct a house.

Bundles are groups of assemblies with a common use or theme. For example, a Health Care bundle might contain a variety of assemblies that aid in creating health care models. When you download assemblies from the isee Exchange™, you download an entire bundle, rather than individual assemblies.

Categories are subgroups of assemblies within a bundle. For example, a Health Care bundle might contain a Funding category for assemblies related to the management of hospital funds. All assemblies must be assigned to a category—they cannot be assigned to the root of a bundle.

Assemblies, bundles, and categories can be created and uploaded to the isee Exchange™ via the options on the Manage My Assemblies page. To learn more, visit our help pages, or take our assemblies tutorial.

Sim App (Sim)

An interface that allows users to interact with a model.

Image of a sim

Sim apps allow users to interact with a model using buttons, sliders, knobs, tables, graphs, and storytelling. These interactions help users understand how parts of a system interact.

Interfaces are created by model authors in the Stella desktop software and can be uploaded to the isee Exchange™.

Model

A diagram that represents how elements in a system influence one another.

Image of a model

Models are mathematical representations of how elements in a system are connected and interact (e.g., ecosystems, organizations, supply chains). When running models on the isee Exchange™, results can be viewed in output devices like graphs and tables.

Models appear in the isee Exchange™ directory when authors upload them from the Stella® desktop software or create them with Stella Online™.

Causal Loop Diagram (CLD)

A map that represents the feedback structure of a system.

Image of a CLD

CLDs are high-level maps that represents the feedback structure of a system and easily communicate the essence of a model. They appear in the isee Exchange™ when authors upload them from the Stella desktop software or create them with Stella Online™.