Misconceptions in life sciences

Last month, I was involved in teaching on a life science communication course, some of the results of which you can see on Wikipedia. One of our guest speakers was Alom Shaha, who demonstrated the misconceptions students have about e.g. the forces acting on a ball in flight:

The ball has recently been thrown from the left of the image, the ground is beneath it.

Invoking a force to account for the rightward motion of the ball is a very common misconception.

This got me thinking that it might be worthwhile cataloguing some of the commoner misconceptions my students have in the biochemistry and biology topics I teach. Like the Perl tutorial, this will be a work in progress: I’ll post larger articles on these topics as I find time.

• Succinate dehydrogenase (SDH) produces reduced flavin (FADH₂) as a product
• The end product of glycolysis is pyruvate
• The sign of standard free energy change (∆G⁰) determines whether a reaction will proceed
• An enzyme lowers the activation energy for a reaction
• An enzyme increases the rate of product formation
• Enzymes in cells can be modelled using the Michaelis Menten equation
• An electrogenic pump is required to generate a membrane potential
• The hydrophobic effect is a result of van der Waals attraction between fatty molecules
• ‘Gene’ has a rigorous definition
• mRNA is a bland photocopy of the information in DNA
• A P value is the probability that the null hypothesis is true
• The answer to any question about improving an experiment is ‘more repeats’
• Bacteria take up environmental DNA by transformation in order to gain new features
• The problem with Lamarckism is the inheritance of acquired characteristics
• The term ‘missing link’ is meaningful
• Evolution is synonymous with natural selection
• Organisms evolve adaptations to increase their fitness
• Some organisms, like cycads, are living fossils
• Some groups of organisms, like magnolias, branched off early in the history of life
• Some organisms, like Psilotum, are primitive
• Junk DNA is a disproven myth

*My version would be something like this:

I’m sure this merely points outs my misconceptions about fluid dynamics rather than those about Newton’s Laws. Drag and lift are the components of the aerodynamic force resolved parallel and perpendicular to the direction of motion of the ball; they will depend on whether/how the ball is spinning. I think there will also be a tiny buoyant up-thrust opposed to the pressure gradient of the Earth’s atmosphere, but don’t know if this gets subsumed into the aerodynamic force somehow.