Paul Andersen describes how free energy is used by organisms to grow, maintain order, and reproduce. A brief discussion of the first and second law of thermodynamics is also included. Disruptions in the amount of free energy can cause...

In this video Paul Andersen explains how magnetic domains act as tiny magnets within ferromagnetic material.

In this video Paul Andersen explains how electric charge is quantized and how the smallest unit of charge is 1.6x10^-19 C, or the elementary charge. Robert Millikan discovered the elementary charge using the oil drop experiment....

Paul Andersen explains how feedback loops allow living organisms to maintain homeostasis. He uses thermoregulation in mammals to explain how a negative feedback loop functions. He uses fruit ripening to explain how a positive feedback...

Mr. Andersen gives a brief description of osmosis. He explains how water moves from a hypotonic to a hypertonic solution across a semipermeable membrane. The video ends with a time-lapse demon in class.

In this video Paul Andersen explains how the dimensions of space and time are combined in relativistic mechanics. Gravity and velocity can affect both space and time according to Albert Einstein's Special Law of Relativity.

In this video Paul Andersen explains how you can combine the power of a Punnett square for an entire gene pool. Hardy-Weinberg equilibrium will remains constant under several constrains and the probability square makes the information...

In this video Paul Andersen explains how biogeochemical cycles move required nutrients through the abiotic and biotic spheres on our planet. Matter on the Earth is conserved so producers must receive required nutrients through the water...

In this video Paul Andersen explains how air pollution is any chemicals in the atmosphere that negatively affect human health. Primary pollutants (like CO, VOCs, NOx, SO2, PM, and Lead) as well as secondary pollutants (like Ozone, nitric...

In this video Paul Andersen explains how Kirchhoff's Junction Rule can be applied to series and parallel circuits. Kirchhoff's Junction Rule is an application of the conservation of charge. The current into a junction will always equal...

Paul Andersen describes four important homeostatic loops in biology. He begins with a brief description of the elements of a homeostatic loop. He then describes how the hypothalamus helps us maintain a stable internal body temperature....

In this video Paul Andersen explains how the macroscopic measure of temperature can be related to the average kinetic energy of molecules in motion. The Boltzmann constant and distribution can be used to calculate the root mean square...

In this video Paul Andersen explains the elements in the Hardy-Weinberg equation; including the allele frequency and phenotype frequency. He begins with a brief explanation of phenotypes and genotypes. A sample problem is worked out and...

In this video Paul Andersen describes the history of calorimetry and explains how it can be used to measure energy changes in a system. The specific heat of water is well established and so as a system releases or absorbs energy from a...

In this video Paul Andersen explains how equipotential lines show equal electric potential in an electric field. Equipotential lines can be created from scalar values or by observing the electric field lines. An charged object can move...

In this video Paul Andersen explains how stratospheric ozone protects humans from ultraviolet light. He explains how stratospheric ozone is formed when diatomic oxygen absorbs an ultraviolet photon and is split into two free oxygen...

In this video Paul Andersen explains how to run the student's t-test on a set of data. He starts by explaining conceptually how a t-value can be used to determine the statistical difference between two samples. He then shows you how to...

Paul Andersen explains how epinephrine is responsible for changes in chemistry of our body associated with the fight or flight response. Epinephrine released by the adrenal medulla are received by a number of organs associated with the...

In this video Paul Andersen answers this question about chromosomes. He explains how the base pairs of DNA form genes which are organized into the chromosomes of the overall genome.

Paul Andersen explains how genotypes can be expressed or not based on changes in the environment. He starts with a brief description of the Himalayan rabbit and how melanin production can be disrupted by high temperature. He explains how...

Mr. Andersen shows you how to convert moles to grams and moles to molecules.

In this video Paul Andersen explains how the electric field strength is directly related to the amount of charge that generates the field.

In this video Paul Andersen explains how variation is created in a population over time. Variation in offspring is caused by genetic recombination, mutations and environmental effects. Parental DNA is recombined using the process of...

In this video Paul Andersen explains how the center of mass of an object represents the average position of matter in an object. The center of mass of a system is a combination of all the objects within the system. As long as no external...