Profile

• Time Zone

  Eastern

  
  
• Organization

  Heliponix

  
  
• Role

  Scientist Mentor: I will mentor teams of students online

  
  
• Research Interests (300 words)

  Plants seem so boring, right? They just sit there and do nothing. But this is what makes plants special. Unlike other lifeforms, plants cannot run away. Plants may not seem active, but they have complex systems to respond to everything that happens in their environment. I study seeds and how they decide when to sprout, and roots and how they change their growth when there is a not enough water.

  
  

  Seeds are green and alive when they are made on the plant, but then they become dry and are almost dead. They can sit dry for a long time and do nothing. Then one day if they have the right conditions, they come back to life and sprout. Some seeds require fire to germinate. Others require cold. Some must sit for years before they are ready.

  
  

  Plants hormones help the seed decide when to sprout. Changes in plant hormones can also change how the roots will grow when they need to find water. I harvest seeds and roots under different experimental conditions and measure the levels of plant hormones to see how hormone levels are changing and try to understand how plants control these processes.

  
  

  I also look at changes in levels of gene transcripts in plant cells. Plants have DNA, just like humans, and DNA makes transcripts (RNA), which make proteins. Proteins can be part of machines in the plant or make up physical structures. Plant hormones can stimulate specific transcripts to be made which carry the code for the needed proteins. So a tiny change in hormones can signal the time to sprout. Or tell the plant to mobilize defenses to a predator. Or turn the roots towards water. The more I study them, the more I find that plants are anything but boring.

  
  
• Profile Question 1

  What is your favorite plant? Why?

  
  
• Answer the question you selected for profile question 1 here (300 words):

  It’s really difficult to pick just 1 favorite plant, but one plant that I think is really cool is the Japanese Cedar tree. I used to live in Japan and I would see these trees when I went hiking in the mountains. The trees have religious significance in Japan and are often found around temples or shrines wrapped with rope and paper ornaments.

  
  
  

  What makes them so cool is that they emit a compound into the air that can affect the growth of other plants nearby. The compound is called ent-kaurene, and it is near the top of the pathway that the plant uses to make a plant hormone called GA (gibberellin). GA makes plants grow taller, helps plants decide when to flower, and tells seeds that it is time to germinate.

  
  

  We know that ent-kaurene can travel from one plant to another because we can test it experimentally. If I have a mutant which can’t make GA because the first step in the pathway to make GA doesn’t work, then the plant won’t germinate. I can add GA and get it to germinate, but if I stop there it will be very short. So I need to keep adding GA to make it grow tall and flower.

  
  

  If I put a small Japanese Cedar tree next to this plant, then the plant can use the ent-kaurene from the Japanese Cedar to make GA. Ent-kaurene is the third step in the pathway, so we can skips step 1 and 2 and the plant can do the rest of the steps to make GA. These plants will grow tall and produce flowers just like non-mutant plants.

  
  
• Profile Question 2

  What is the coolest thing you have discovered or learned about plants?

  
  
• Answer the question you selected for profile question 2 here (300 words):

  One of the coolest things about plants is how they can defend themselves with out being able to run away. A classic example of this is how plants enlist insects to defend them from attack.

  
  
  

  Plants can sense when insects like caterpillars are crawling on them or munching on them and release a plant hormone called JA (Jasmonic acid) that helps them defend against these pests. But a lot of plants take it a step further, but releasing Volatile Organic Compounds (we call them VOCs) into the air when they get chomped on. Think of the smell after you mow the lawn. A lot of the smell of fresh-cut grass is VOCs released from the grass. A plant getting eaten by a caterpillar can release VOCs that travel far away and attract parasitic wasps. The wasps come and attack the caterpillar. It’s a sort of booby-trap set up by the plant to protect itself.

  
  
• Profile Question 3

  What is best about being a scientist?

  
  
• Answer the question you selected for profile question 3 here (300 words):

  The best thing about being a scientist is that you are literally on the cutting edge everyday. The experiments you perform are uncovering knowledge that nobody in the whole world knew before. That’s really exciting! And anybody can do science. It doesn’t take a genius or amazing good luck to make a discovery. All it takes is careful planning and a lot of hard, repetitive work. Being a good scientist means doing things over and over enough times that you know you can trust the results. It means testing your hypothesis by a couple of different methods to make sure that you are interpreting the results correctly. It means discussing your findings with other scientists and listening to their feedback, even when it disagrees with your ideas. Being a good scientist doesn’t mean that your hypothesis will be correct the first time — it almost certainly will never be right the first time! But have patience and the results of every experiment you do will point you towards new hypotheses and eventually you will be adding a little bit to the global pool of human knowledge. That’s the best thing about being a scientist. Your job is to discover new knowledge and share it with the rest of the world.

  
  
• Availability

  I am NOT available, please temporarily remove me from the available mentor list

  
  
• Capacity: How many teams at a time are you comfortable working with?

  1

  
  

Recent Posts

pvhsapplemanposfall2023 project 6 Sven Nelson Nov 13, 2023

Interesting!  I wonder if you will see a correlation between heart rate and CO2 produced or if you will see a bigger impact of the individual person who is doing the exercise.  Do any of you do play sports or exercise a lot?  

pvhsapplemanposfall2023 project 6 Sven Nelson Nov 6, 2023

That's interesting.  It's nice to see that your experimental results agree with each other.  Sometimes in scientific research that doesn't happen and then we have to figure out why and what the difference was.  It…

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That's interesting.  It's nice to see that your experimental results agree with each other.  Sometimes in scientific research that doesn't happen and then we have to figure out why and what the difference was.  It still generally ends up being useful and maybe we discover that a factor we didn't think was important is what's causing the difference.  

What did you use for your light source?  Is is just the classroom lights or do you have some sort of light source just for this experiment?  If so, do you know what type of light that is?  Normal light bulb?  LED lights?  Fluorescent lights or something else? 

I ask because the different types of lights will have different light spectra.  Even with one type of light, you can sometimes tell that a room feels like it has more warm light (more yellow/orange) and other times you feel like the light is more "cold" (very white/blueish tint).  This is referred to as the color temperature of the light.  Different color temperatures are better for flowering or for vegetative growth.  In a field in the main growing season the sun is overhead and the light is more towards the blue range and plants are growing a lot of leaves and other vegetative tissues.  Then at the end of the summer and start of fall the sun is low in the sky and this causes the color temperature of the light that passes through the atmosphere to be more towards the red range, which triggers the plants to start flowering and producing fruit or grain in preparation for the end of the season.  

What's the impact of color temperature on photosynthesis?  Photosynthesis is happening in both cases, so it's not straightforward to answer.  It would be interesting to do an experiment to see what the results tell us.  ;) 

plants Sven Nelson Oct 31, 2023

I'm curious what your future plans are for similar experiments.  What colors would you test next and what do you expect to see?  

Is there anything with your current experiment that you think could be improved and might change…

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I'm curious what your future plans are for similar experiments.  What colors would you test next and what do you expect to see?  

Is there anything with your current experiment that you think could be improved and might change the results?  It has been fun to hear about your experiments!