Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Fast Plant Lab
Transcript of Fast Plant Lab
Selection: Technical Study
of Wisconsin Fast Plants
Fast Plant Lab
Background of Evolution
Evolution is the founding principle
of modern biology. After a mutation
has occurred, an organism's fitness
may be unaffected, reduced, or
increased. If the fitness is increased,
that organism is more likely to pass
that gene on to future generations.
This may cause the population to
shift toward that genotype over
time. This shift over many
generations is known as
The observed effect of artificial selection is that the number of trichomes in the F1 generation varied significantly from the number of trichomes in the P generation.
“Artificial Selection of Plants Through Selective Breeding.” Selective Breeding of Plants. Web. 18 Jan. 2013.
“History.” Wisconsin Fast Plant Program. Web. 18 Jan. 2013.
“Life Cycle.” Wisconsin Fast Plant Program. Web. 18 Jan. 2013.
Tyrell, Jennifer. “Chapter 17 Notes.” AP Biology Jefferson County High School, Dandridge, TN. 10 Sept. 2012. Lecture.
Artificial selection is crucial to
modern life. The food mass
produced throughout the world
has only come about due to
natural selection. Broccoli, kale, cauliflower, brussel sprouts, and
cabbage are all domesticated
strains of the wild mustard
plant, Brassica oleracea.
Dr. Paul Williams
Dr. Paul Williams, professor in the Department of Plant Pathology at the University of Wisconsin-Madison, was studying the pathology of cruciferous plants (a group including broccoli, mustard, and many others) and attempted to breed a plant with a shortened life cycle and living conditions conducive to laboratory research. Most importantly, however, Dr. Williams had shortened the six-month life cycle of the B. oleracea to a mere five weeks for the B. rapa. The shortened life cycle proved useful to scientist because Wisconsin Fast Plants enable many advances in cellular and molecular plant
Fast Plants are angiosperms and, more specifically, dicots. Like all angiosperms, Fast Plants have flowers and fruits that bear seeds. The life cycle of a Fast Plant—from planted seed to harvestable seeds—is approximately 40 days.
In this experiment, all plants with fewer than fifteen trichomes were thinned and not allowed to reproduce in the next generation. The purpose of this experiment was to observe the effects of artificial selection over three generations (P, F1, and F2) of Fast Plants. The P generation functions as a control for the number of trichomes present in the absence of evolution or artificial selection. The independent variable is the plants allowed to reproduce in the next generation on the basis of trichome number. The dependent variable is the number of trichomes present in the following generation. The life cycle was closely monitored for any changes or variation in plannt growth or development. Through each successive generation a significant increase in the number of trichomes present is expected.
If Wisconsin Fast Plants with fewer than fifteen trichomes are removed from the population, the number of trichomes will increase significantly from generation to generation because artificial selection will inhibit the plants with fewer than fifteen trichomes from contributing that phenotype to the next generation.
Chi-Square is a statistical analytical method used to determine whether the observed results varied significantly from the expected values. Because the experimental hypothesis states that the number of trichomes observed will vary significantly form generation to generation Chi-square must be employed. Chi-square employs a null hypothesis that is either excepted or rejected after calculations. The mathematical equation for Chi-square is defined as the quantity of the observed number minus the expected squared divided by the expected. This value is a reference number that is then used in a table of p values. “p” is the percentage chance that the variance occurred merely be chance and not due to some other factor.
In this experiment, artificial is successful if the number of trichomes observed in the two filial generations could not happen merely by chance. This is because the number of observed phenotypes should remain relatively constant from generation to generation if evolution is not occurring. The null hypothesis for both the F1 and F2 generations was rejected, which concludes that the number of trichomes did vary significantly from generation to generation.
the variance between the F2 and P generations had less than a 0.01% chance
This was proven by a Chi-square statistical analysis, which revealed that the variance between the two filial generations had a less than 0.05% chance of occurring merely due to chance, and further revealed that the
of occurring merely due to chance. Because the number of trichomes increased significantly from generation to generation the hypothesis is supported, and artificial selection in favor of greater trichome numbers was proven successful.
This experiment allowed researches to not only gain insight into the effects of artificial selection, but macroevoltuion was occurring within the laboratory. Invaluable knowledge was gained about evolution and artificial selection in addition to the reproductive systems and life cycles of angiosperms.
As we all recall, the procedure of this lab was very long and involved. We began by planting each generation, care for the plants, and recording careful observations of the life cycle and trichome
This experiment focused on the variation in trichomes number among plants of the Fast Plant population, while also closely monitoring the life cycle of the plants. Trichomes are fine outgrowths that function in plant defense. According to a study by the University of Texas, there exists an inverse correlation between trichome density and insect feeding, especially in regards to phytogeous insects. Thus, an increase in the number of trichomes would decrease insect feeding and increase the fitness of the plants.
Careful Note-taking skills
Plant part differentiation
Chi-square statistical analysis