- Slides: 12
Weird True & Freaky: Animal Planet Today’s Schedule 1. Video of the Day 2. Probability & Genetics 3. Assignment
Probability & Genetics You are going to flip your coin 20 times. Predict how many times the coin will be “heads up” and “tails up” Record the results of each flip. Probability- the likelihood that a particular event will occur.
Principles of Probability What is the probability that a coin tossed 1 time will land “heads up”? The probability would be: 1 in 2 or 50% What is the probability that a coin tossed 20 times will land “heads up”? We would expect it to be 10 in 20 or 50% But, this is not always the case. We might have 12 in 20, 15 in 20, or maybe 7 in 20.
Genetics & Probability Mendel recognized that the principles of probability could be used to predict the results of genetic crosses. What is the probability that the hybrid pea plants would be tall? 3 in 4 or 75%
Genetics & Probability How do we predict genetics? Punnet Square- a chart that shows all the possible combinations of alleles that can result from a genetic cross. Punnet Squares help scientists predict the outcome of a genetic cross.
Phenotypes & Genotypes Phenotype- an organisms physical appearance, or its visible traits Genotype- an organisms genetic makeup or allele combinations
Phenotypes & Genotypes Homozygous- an organism that has two identical alleles for a trait. (homo = same) Heterozygous- an organism that has two different alleles for a trait (hetero = different)
Codominance What happens when two organisms reproduce and there is not a dominant or recessive allele? Both alleles will be expressed in the offspring. Codominance- neither allele is dominant or recessive
A closer look. Punnett Squares Drag-and-Drop Genetics: Monohybrid Punnetsquares punnet square interactive
Make the Right Call Skills Lab Making predictions is an important part of science. An accurate prediction can be a sign that you understand the event you are studying. In this lab you will make predictions as you model the events involved in genetic crosses. Problem: How can you predict the possible results of genetic crosses? Materials: 2 Paper Bags, 2 red beans and 2 white beans
Data Table 1 Trial Allele From Bag 1 Allele From Bag 2 (Female Parent) (Male Parent) 1 2 3 4 5 6 Offspring’s Alleles
Analyze & Conclude Punnet Squares