Director of Natural Areas and Curator of Botany Dr. Jim Bissell explains why it's important for us to care for native plants in Northeast Ohio and gives us a look at the collections of the Botany Department. Worksheet available for grade 5.

Use the principles of physics to understand the force of a bouncing object. [6:49]

An overview of how chromosomes were first proposed as the carriers of Mendel's "heritable factors" or what we now call "genes". [10:58]

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A narrated screencast demonstrates the relationship between pressure and volume of a gas at constant temperature. [7:08]

Paul Andersen shows you how to use a sphygmomanometer to measure the systolic and diastolic blood pressure. The the describes the elements of the laboratory portion. The temperature is gradually lowered and the respiration rate of a goldfish is measured. [4:30]

Paul Andersen explains how pigments can be separated using chromatography. He shows how you can calculate the Rf value for each pigment. He then explains how you can measure the rate of photosynthesis using leaf chads and water containing baking soda. [5:42]

Paul Andersen details the first 7 of 13 labs in the AP Biology Curriculum. The following topics are all covered: Artificial Selection, Hardy-Weinberg Equilibrium, Comparing DNA using BLAST, Diffusion and Osmosis, Photosynthesis, Respiration, Mitosis and Meiosis. [13:26]

Paul Andersen shows you how to write balanced equations that describe chemical changes. He then gives you a short introduction to balancing equations and uses the PHET site to practice this skill. [9:39]

Paul Andersen explains how atoms are conserved in a chemical reaction. This can be seen in a chemical equation where the subscripts represent the atoms in the molecule and the coefficients represent the molecules. The mass of an anylate can be determined through both gravimetric analysis and a titration. [12:18]

In this video, Paul Andersen explains how we can use Coulomb's law to predict the structure of atoms. These predictions can be verified through the use of Photoelectron Spectroscopy (PES). [10:57]

In this video, Paul Andersen explains how ionic solids form a lattice between cations and anions. According the Coulomb's Law the lattice energy increases as the ions carry a larger charge and are smaller. Some of the properties of ionic solids are high melting point, low vapor pressure, brittleness and the inability to conduct electricity. [5:05]

Paul Andersen explains how you can use Lewis Diagrams and VSEPR Models to make predictions about molecules. The Lewis diagrams are a two-dimensional representations of covalent bonds and the VSEPR models show how the molecule could exist in three dimensional space. [12:29]

In this video, Paul Andersen explains how a spectrometer was used to identify the presence of isotopes. This modified Dalton's original atomic theory because atoms of the same element had different masses. The functional parts of a mass spectrometer are detailed including the ionizer, mass analyzer and the detector. [8:19]

Explains how metallic bonding structure creates the different properties of metals. The electron sea model explains how the positive nuclei are locked into a negative sea of delocalized electrons. This sharing of electrons creates metals that are good conductors, malleable, ductile, and non-volatile. [5:54]

Paul Andersen describes the structure and explains the properties of molecular solids. High intramolecular forces hold electrons and reduce conductivity, whereas low intermolecular forces decrease the melting point. Important polymers can be formed from monomers and have both commercial and biological value. [3:48]

In this video, Paul Andersen explains how elements and molecules are made of atoms. In a pure sample of a pure substance the average mass remains the same. If more than one atom is found in a molecule the ration of average masses remains the same. [6:08]

In this video, Paul Andersen explains why atoms in the periodic table show trends in ionization energy, atomic radii, electronegativity and charge. All of these trends are explained through Coulomb's Law. A brief description of Dmitri Mendeleev and the power of predictability are included. [8:47]

Paul Andersen compares and contrasts the properties of solids and liquids. Solids have a more organized structure which can either be amorphous or crystalline. In liquids the intermolecular forces are lower and so the molecules can show translation. [7:28]

Paul Andersen reviews the major within the first unit on natural selection. He starts by defining evolution and explaining how evolution can occur in a population. He reviews the population genetics and camouflage lab. [13:04]