B Block Phototropism Results

Data Jenn, Annie, Felicia Box Design The plants did not grow at all. Day Growth of Plant 1 0 cm 20 Hypothesized direction of growth light

Analysis Why didn’t the plant grow? What should have happened? Since the plant did not grow, no conclusion regarding phototropism was derived. Why didn’t the plant grow? One of the seeds was split in half and the other was not found. They died. What should have happened? Theoretically, the plants should have grown downwards and bent around the cardboard obstacles towards the light source at the bottom.

A Study on Post Mortem Plant Growth A Scientific Journey ft. Mikel, Karthik, and Shyam

Design Two holes were cut on the sides of the box allowing light in A barrier was assembled to insure the plant grew in a Y shape. But that didn’t work.

Data Day 1 to Day x: 0 cm tall :( SEM: 0! Graph: Growth (cm) Time (days) Conclusion: Our plants are probably dead

Plant Growth Analysis: A Study on Post Mortem Plant Growth Our plant showed no growth despite one of the seeds germinating. This was most likely due to human error, as all of the seeds were damaged when the CD case was opened. Parts of the seeds had plastered to the cover of the case. If our plant had grown, we predict it would have looked like the picture to the right

Phototropism Laboratory By: Alex Cardeiro, Ryan Ditcham, Jonathan Townsend

The Low Down We put a barricade to prevent the sun from coming in the middle of the shoe box We expected the plants to grow around the barricade It worked!

Plant Data

Analysis As the plants grew taller, they curved around the board in the middle of the box This happened because of the plant hormone cytokinin, which allows the plant to grow laterally This is what we expected to happen, because we thought the plant would curve to "seek out" the sunlight

Phototropism Lab Presentation By: Olivia Gregg, Shannon Molloy, Eric McCord, Jimmy Ward

What we saw happen was… Something go wrong with our plant and the shoot detached from the root, therefore we saw no growth apically or laterally. That happened because…. We are not one hundred percent sure what happened to our plant. We think the box it was in could have been hit and the shoot could’ve snapped off. We tried for lateral growth as well, but that did not happen because there was not enough light to let it grow at all. What we expected to happen was… The plant would grow towards the direction of the the light that was reflecting off the mirrors.

Data Summary We observed growth of only 2 cm after our plant stem broke early in our experiment, possibly due to movement in the box or being cut. We then looked for lateral growth but none was observed.

Shannon, Aine, Jillian, Nancy Phototropism Lab Shannon, Aine, Jillian, Nancy

Plant 1 (Jeremy the Jer-minator) Growth Data Summary Date Plant 1 (Jeremy the Jer-minator) Growth Plant 2 (Doris) Growth 3/10/15 2.9 cm 0 cm 3/11/15 decapitated, 3.1 cm 3/12/15* dead/moldy decomposing; 0 cm * project was discontinued as both plants showed signs of decay

Analysis Expected: If light is blocked from all sides of the plant excluding the bottom, then the plant will grow laterally due to cytokinins and downward due to the effects of phototropism and blocking of apical stem growth. Observed: plants both died unknown cause- no results Possible Explanation: dehydration (though we watered them every day) lack of light→ very little got into the box seed was dead before planted decomposition affected live sprout

by Thomas Sherriff and Siddhant Navali Phototropism by Thomas Sherriff and Siddhant Navali

Summary Phototropism and Gravitropism are the growth patterns in plants in response to certain stimuli such as light and gravity. Auxin plays a primary role in the directional growth of plant stems and roots in response to changes in light and the effects of gravity. In phototropism, Auxin loosens the cellulose in the cell wall to stretch the plant in the direction of the light. Gravitropism works in reverse, forcing the Auxin to the bottom side of the roots to inhibit the loosening of the cell wall, allowing for the upper cells to stretch down because of gravity.

Hypothesis If the seeds are placed standing up in four orientations, then the roots will grow towards the pull of gravity and the stems will grow against the pull of gravity because of Auxin’s role in directional growth If the seeds that are showing growth are placed in a container with a limited light source, then the stems will grow towards the light because of Auxin’s role in directional growth

Baby Picture <3

Pictures Middle End

Data Height (centimeters) Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Plant 1 9.5 12.5 18.5 21.5 26 26.5 Plant 2 8 10 15 17 18 7* Plant 3 9 Plant 4 6 6.5 Plant 5 4 * this plant folded over because it could not support itself and dried out

What Happened? The first two plants grew towards the light very quickly, and within days reached their maximum potential for growth. They stunted at 26.5cm and 18 cm respectively. This was expected as they grew around the cardboard that was blocking sunlight in order to grow towards the one opening with light. The other three plants grew a little bit, but they were left in the dark for too long and so they stopped growing vertically, and it seemed that all of the plants stopped growing at one point. On day 6, the sides that the plants were on flip-flopped, so plants 1 and 2 were in the dark while plants 3,4, and 5 were exposed to light. However, minimal growth occurred.

Why it happened? Plants 1 and 2 grew quite quickly because the auxin directed them to grow towards the light. However, once they reached a certain point, they stopped growing because otherwise they would have become too tall and would not have been able to support themselves, as evidenced by what occurred to plant two on the final day. Plants 3, 4, and 5 grew vertically with little exposure to light when they were placed on the right side of the box. However, by the time we switched the sides that the plants were on, their growth had already stunted and they had stopped producing auxin. Therefore, even when they were placed underneath the cardboard, closer to the light source, they did not grow toward the light and simply maintained their growth.

Nam Le, Manoj Malipeddu, Thien Vu Plant Tropism Lab Nam Le, Manoj Malipeddu, Thien Vu

Gravitropism Data Plant Day 1 (cm) Day 2 (cm) Day 3 (cm) Day 4(cm) Right Top 6.25 8 9.5 Right Bottom 4.25 8.25 9 10 Left Top 2.5 3 10.5 Left Bottom 6 13 Bottom Right 1 Bottom Left Top Right Top Left

Phototropism Data Plant Day 6 (cm) Day 7 (cm) Day 8 (cm) Day 9 (cm) 1 19 22 23.5 28.7 29 25.5 26 2 14 17 21 24 25 28 28.5 3 15 29.2 29.7 30 27

March 5

March 6

March 11

March 13

March 16

March 23

Analysis The plants just kept growing straight up. Before the piece of cardboard was taken out on March 11, the plant grew to the horizontally because the piece of cardboard was preventing it from growing up. However once it was removed, the plant began to grow straight up again like on March 16.

Analysis Continued The plant grew horizontally while the piece of cardboard was there because it could not grow vertically. However once it was removed it had a lot of space to grow vertically and so it did. We did not think we were going to remove the cardboard so we thought the plant would grow horizontally the whole time. But, we did take out the piece of cardboard and so after we removed it we expected it to grow vertically once again.