Jon Darkow's Work

We found 62 items

#1 - Lactase Enzyme Simulation with Data Analysis

by Jon Darkow - 804005 runs
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#2 - Photosynthesis Model

by Jon Darkow - 118639 runs
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#3 - Evolution and Natural Selection

by Jon Darkow - 86318 runs
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#4 - Population dynamics of white footed mouse

by Jon Darkow - 90749 runs
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#5 - Information Processing and Neurophysiology Model

by Jon Darkow - 67940 runs
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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.

#6 - Evolution of LAP Allele in Mussels

by Jon Darkow - 24177 runs
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#7 - Lac Operon with Monod Bump

by Jon Darkow - 34197 runs
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#8 - Lactase with Variable Sample Sizes

by Jon Darkow - 43110 runs
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Arrayed Lactase Model

#9 - Lactose Operon: An Inducible System

by Jon Darkow - 25622 runs
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In this simulation users explore the negative feedback system of the Lactose Operon found in bacteria. Lactose induces the system by inhibiting and inhibitor.

#10 - Cellular Respiration Accounting Model

by Jon Darkow - 25566 runs
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The purpose of the model is to understand how glucose is metabolized, and how the energy stored in its chemical bonds is transfered.

#11 - Limiting Nutrients in Aquatic Ecosystems

by Jon Darkow - 17068 runs
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Experiment with a variety of nutrients that are limited by different degrees in four different ecosystems.

#12 - Water Potential and Osmosis

by Jon Darkow - 23422 runs
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Factors that affect the flow across a semi-permeable membrane.

#13 - Diffusion of a Spherical Cell

by Jon Darkow - 9696 runs
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Why are cells small? This model allows users to see how the size of a sphere affects the rate of diffusion.

#14 - Photosynthesis with Variable Sample Sizes

by Jon Darkow - 7633 runs - 24 downloads
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Sample sizes of Photosynthesis stocks in an array

#15 - Thyroid Hormone - Negative Feedback

by Jon Darkow - 7835 runs
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#16 - Recombination and Gene Linkage

by Jon Darkow - 27581 runs
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#17 - Transformation Simulation

by Jon Darkow - 8714 runs
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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.

#18 - White-Eyed Genetics

by Jon Darkow - 18557 runs
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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?

#19 - Apterous Genetics

by Jon Darkow - 59045 runs
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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?

#20 - Extinction Vortex

by Jon Darkow - 5885 runs
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#21 - Steady State in Freshwater Ecosystems

by Jon Darkow - 12306 runs
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#22 - Evolving Bits

by Jon Darkow - 1400 runs
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Diversity and selection for the basis of evolution. This simple model tries to illustrate these concepts.

#23 - Evolution with Heterozygous Advantage

by Jon Darkow - 3283 runs
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Evolution of Populations: Genetic Drift, Natural Selection, and Mutations

#24 - Growth Factors, Cyclins, and Cancer

by Jon Darkow - 45119 runs
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Explores the feedback loops that regulate the cell cycle. Model focuses on manipulating stimuli (growth factors), to stimulate the cell cycle feedback loops.

#25 - HPV and Adaptive Immune Response

by Jon Darkow - 4074 runs
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#26 - Tryptophan Operon: A repressible system

by Jon Darkow - 13204 runs
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#27 - Guppy Evolution

by Jon Darkow - 3676 runs
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#28 - Circadian Clock in the Mouse

by Jon Darkow - 9127 runs
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Transcriptional Translational Feedback Loop in the Mouse

#29 - Tick Tock: The Biological Clock and Circadian Rhythm

by Jon Darkow - 791 runs
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Explore gene expression of the transcriptional-translational feedback loop (TTFL) of the mouse circadian rhythm.

#30 - Pattern with recessive single band

by Jon Darkow - 13666 runs
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#31 - Phenology of the Karner Blue Butterfly

by Jon Darkow - 2675 runs
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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.

#32 - Evolving Bits N=40

by Jon Darkow - 1066 runs
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#33 - Tesing Unknown Enzymes

by Jon Darkow - 2891 runs
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#34 - Logistic Growth Model

by Jon Darkow - 323 downloads
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#35 - Logistic Growth Model and the Butterfly Effect

by Jon Darkow - 755 runs
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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.

#36 - Neurophysiology and Neurotoxicity

by Jon Darkow - 16768 runs
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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.

#37 - Exponential Growth in Population - AF

by Jon Darkow - 255 downloads
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Chapter 2: Modeling the Environment

#38 - Chaos Theory: Strange Attractor

by Jon Darkow - 341 runs
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Manipulate the main variables of the Lorenz equation.

#39 - Evolution: Grants Finches

by Jon Darkow - 1036 runs
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Models the effects on population sizes of ground finches with different beak sizes in response to different amounts of annual precipitation.

#40 - Chapter 2: Population Growth

by Jon Darkow - 162 downloads
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Chapter 2 introduction

#41 - System Dynamics of Carbon Budget

by Jon Darkow - 1247 runs
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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)

#42 - Lotka-Volterra Predator-Prey Model

by Jon Darkow - 888 runs
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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.

#43 - Genotyping with Electrophoresis

by Jon Darkow - 1385 runs
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#44 - Enzyme Diversity: Enzymes, Products, and Substrates

by Jon Darkow - 24328 runs
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#45 - Chapter 2.12

by Jon Darkow - 134 downloads
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#46 - Catastrophic Regime Change in Aquatic Ecosystems

by Jon Darkow - 1162 runs
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#47 - Cellular Respiration Inquiry

by Jon Darkow - 28771 runs
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Model of the dynamics of the metabolism of one mole of glucose. Randomness is built into the computations.

#49 - HPV with Influenza A Humoral Immunity

by Jon Darkow - 141 runs
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Immune response of HPV

#50 - Beta Cell Membrane Transport - Insulin Regulation

by Jon Darkow - 211 runs
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#51 - The dynamics of photosynthesis - variable sample size

by Jon Darkow - 38 runs
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The dynamics of photosynthesis - variable sample size

#52 - Stock, Inflow, and Outflow with Atrazine

by Jon Darkow - 39 runs
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Simple stock and flow diagram. Flows linear.

#53 - Beta Cell Simulation - Split story

by Jon Darkow - 1819 runs
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#54 - Fruit Fly Choice

by Jon Darkow - 153 runs
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Simulation to model random behavior in a fruit fly choice chamber

#55 - Photosynthesis Simulation with Variance

by Jon Darkow - 36492 runs
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#56 - Fruit Fly with variable sample size

by Jon Darkow - 39 runs
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#57 - Simple Genetics

by Jon Darkow - 15664 runs
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#58 - Carbon in the Atmosphere - Graphic Input constant

by Jon Darkow - 25 runs
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#59 - Oxytocin and Child Birth

by Jon Darkow - 18690 runs
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#60 - GLUT and Insulin

by Jon Darkow - 10 runs
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#61 - Cardiovascular Model

by Jon Darkow - 0 runs
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#62 - Grant Finches Mobile

by Jon Darkow - 10 runs
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