genotype phenotype probabilities

Patterns of genetic inheritance obey the laws of probability. In a monohybrid cross, where the alleles present in both parents are known, each genotype shown in a Punnett Square is equally likely to occur. Since there are four boxes in the square, every offspring produced has a one in four, or 25%, chance of having one of the genotypes shown.

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pH

The definition of pH is straightforward: pH describes the concentration (or activity) of positively charged hydrogen ions (H⁺) in a solution. Underlying this definition is a set concepts that can be challenging to understand. The challenge comes from needing to appreciate:

Punnett Square

During sexual reproduction, a parent is equally likely to pass on to its offspring either of the two alleles it has at each genetic locus. This makes it possible to list and estimate the probability of specific genotypes being produced from the pairing of two individuals. Given two allele from each parent, four allele combinations are possible. These combinations and their probabilities can be readily visualized using a Punnett square.
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Serial Dilutions

***UPDATE- View the updated illustration at SciencePrimer.com

Many modern biology and chemistry laboratory procedures require compounds to be mixed or dissolved in a liquid such as water.  These mixtures are called solutions.  Solutions have two components: a solute and a solvent.  Solutes are the suspended or dissolved material and the liquid is the solvent.  The amount of solute present in a particular volume of water or other solvent is called its concentration. For chemicals, common concentration units include weight/volume percent, weight percent, molarity and normality.  For biologically active compounds such as antibodies or enzymes, concentrations are often described using activity units/ml.  Concentration of bacterial and cell cultures are often reported in cells / ml or CFU (colony forming units)/ml.

Alleles, genotype and phenotype

Genetics is the study of the organization, expression and transfer of heritable information. The ability for information to pass from generation to generation requires a mechanism. Living organisms use DNA. DNA is a chain, or polymer, of nucleic acids. Individual polymers of DNA can contain hundreds of millions of individual nucleic acids molecules. These long DNA strands are called chromosomes. Information is contained in the order of the individual nucleic acids that make up the DNA polymer. The use of DNA as the information molecule is a universal property of all life on Earth. Genetic information is read by our cellular machinery and allows our bodies to synthesize the many enzymes and proteins required for life