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Skip to 0 minutes and 3 seconds KAREN HORNBY: So welcome to Bev and Alex. We’ve got some really interesting questions today. And I want to start with the one about culturing. So this is really talking about cost and time with micropropagation and culturing. And do we know any ways of using different agars or cheaper ways to do it or quicker ways to do it? Bev, you want to?

Skip to 0 minutes and 31 seconds BEVERLEY GOODGER: Yeah. I mean, obviously if you’re growing things, you have to give time for cells to divide. So from that point of view, it’s hard to make it quicker. In terms of alternatives to agar, I had a little look around. And there seemed to be some possibilities of using things like alginates or guar gum or any other sort of gummy starchy thing that you can sterilise. But obviously, alginate is the best. I even found somewhere that had tried using arrowroot and aspic and cornstarch to make a gloopy solution. But of course, it wouldn’t gel. It would have to be very concentrated.

Skip to 1 minute and 21 seconds So I’m not sure whether those experiments were unsuccessful, which is why we just use agar at the moment. And as I say, in terms of getting things to grow faster, I don’t think you can. But I think what the SAPS protocol does– and, Alex, perhaps you want to come in on that– means that, although you have to leave it, it’s going to survive because it doesn’t go mouldy.

Skip to 1 minute and 48 seconds ALEX JENKIN: Yeah, I would agree with you on both those points, Bev. I think, I mean, the SAPS protocol particularly, that technique was developed based on how a micropropagation is done in the field. So obviously, in that situation, agar has been found to be the most successful, or indeed most practical thing to be using. And yeah, the idea with the sterilisation is that you would be able to have it–

Skip to 2 minutes and 25 seconds yeah, you would be able to leave the containers for a while and without them going mouldy because you’ve got sterilised material in there. And in times of other– not so much micropropagation, but the other cloning techniques– just the taking a cutting– they do take time to grow. But you should start seeing some root growth within a couple of weeks. It depends on the plant, of course. But yeah, not much really, unfortunately– certainly at this level of being able to speed things up, particularly. So I suppose it’s about how you plan that in.

Skip to 3 minutes and 20 seconds BEVERLEY GOODGER: In terms in general, using plant material, a lot of the SAPS practicals use supermarket plant material. So as long as you can afford to go and buy a bunch of flowers or a couple of basil plants or a bunch of something to section and you can make that do several classes, then you didn’t have wait to grow seeds. You can actually obtain them all through the year– herbs, particularly– to suit the needs of your classes.

Skip to 3 minutes and 54 seconds ALEX JENKIN: Yeah. Yeah, absolutely, Bev. That’s a very good point that you don’t need to grow everything yourself to do plant practicals. All of our practicals are developed to sort of be as efficient as possible, both with resources and with teacher, technician, and student time availability.

Skip to 4 minutes and 17 seconds KAREN HORNBY: Thanks, some really good tips there. We’ll move on now to some subject knowledge questions. Jeanette asks, is there a point in time when plant material in the test tubes will stop respiring?

Skip to 4 minutes and 35 seconds BEVERLEY GOODGER: Yes. [LAUGHS] Yes, when it dies. If you’re going to put a piece of pond weed into bicarbonate indicator, it will survive for a long time, as will algal balls. They can keep going for months. But eventually they will stop. But in terms of running these practicals for a several classes– check me out on this, Alex– but I should imagine your pond weed would stay alive for several days in the bicarbonate indicator. The algal balls will live for months in the bicarbonate indicator. But I think the pond weed, in a closed system, would survive for a couple of days. Over to you.

Skip to 5 minutes and 18 seconds ALEX JENKIN: Yeah. I think you’re probably right. I haven’t tested how long it would survive in the bicarbonate indicator.

Skip to 5 minutes and 32 seconds But the pond weed, yeah, once that’s cut off– I mean, the cuttings will keep. But they won’t keep as well as if you’ve got a whole plant– particularly if you’ve got a rooted plant, obviously, that’s rooted into the substrate, that’ll survive much longer. But in the experimental conditions, yeah, they will start to degrade after a while. But Bev’s right, the algae do survive much longer. And of course, they are free living within the water under normal circumstances. So they are much more suited to being free floating. Whereas, for example, a living pond weed is rooted into the substrate of the soil at the bottom of the water course that it’s in.

Skip to 6 minutes and 31 seconds So without that, in the same way that any other cutting will eventually die, or any other– so like a flower, for example, won’t just keep surviving in water. That would be similar for the pond weed. And, again, for the other, we have the leaf trapped down the side of the test tube. We’ve trapped by the bung. And, again, it’s not getting the nutrients it needs from elsewhere in the plant. So it will eventually, in that situation, break down and stop respiring, yeah.

Skip to 7 minutes and 16 seconds KAREN HORNBY: Thank you for that explanation. We’ve got a question as well from Donna– a really interesting question. Is it true that a Venus flytrap will die if it opens and closes too often without an insect inside?

Skip to 7 minutes and 31 seconds ALEX JENKIN: Yes, that is the case. But I think there’s a misconception around whether– that that’s to do with because it’s not getting the nutrients. So Venus flytraps supplement their nitrogen intake with trapping insects. But actually, a Venus flytrap doesn’t rely solely on insects for its nitrogen intake. So it’s actually thought it’s to do more with energy usage in terms of shutting the trap. So it takes quite a lot of energy for the plant to shut the trap. And so for it constantly to keep shutting its trap if it’s being bothered lots and lots of times, then that can be a problem.

Skip to 8 minutes and 25 seconds But for example, if you’re just demonstrating the trap shutting, as we do in the SAPS video, that’s not an issue to demonstrate that. So the “Can a Venus Flytrap Count?”

Skip to 8 minutes and 41 seconds investigation, that’s not going to harm your flytrap.

Skip to 8 minutes and 48 seconds If the traps are constantly being triggered, then it uses a lot of resources up for the plant. And then it’s also not getting anything out of it. But it’s not because they can’t survive. Or my understanding is, it’s not because they can’t survive without the nitrogen supplement from consuming the insects.

Skip to 9 minutes and 18 seconds BEVERLEY GOODGER: From a classroom point of view, that does mean that you must make sure that, while you want to encourage your pupils to be fascinated by your Venus flytraps, you don’t want them “flytrap bothering.” You don’t want them constantly prodding them. So you’d have to have some degree of understanding, I think, about that explained to the class.

Skip to 9 minutes and 40 seconds KAREN HORNBY: Thank you. We’ve got a question now about water molecules, or the description of water molecules when you’re explaining osmosis from Mrs. Rychnovsky. Is it a good phrase to use, the “concentration of water molecules”? Or should we be saying fewer particles of water or more particles?

Skip to 10 minutes and 8 seconds BEVERLEY GOODGER: Well, shall I start with this one? When we were writing the text, we decided that we would pitch it at GCSE level. And then obviously, we consulted the exam board specifications. And the exam board approved textbooks to sort of help us decide what kind of vocabulary to use. And “concentration of water molecules” is referred to a lot in those sources of information. And, yes, I understand it is almost counter-intuitive because you’re really talking about concentration of solute when you’re talking about concentration of anything. However, that particular piece of information, of course, is intended for the course participants to use as a refresher.

Skip to 10 minutes and 59 seconds And we were trying to pitch it at participants who may be new to teaching or new to teaching biology. And therefore their background in osmosis isn’t as extensive as somebody who’s been teaching for a very long time. So that concept was picked on because it was felt they will come across it in their teaching when trying to develop their own resources. And of course, as with everything on the course, how you use the material, you pick it up and modify it to suit your teaching. I know in the past, people have said, why didn’t you use water potential from the word go? But water potential is a concept that the students are introduced to at A level, not at GCSE.

Skip to 11 minutes and 44 seconds So that’s why we picked that particular concept. But we would expect everybody to mould the information and express it in the way that’s meaningful to them and their students.

Skip to 11 minutes and 59 seconds KAREN HORNBY: Thanks, Bev. We’re going to move on now to field work– a few questions about field work. And this started off quite a bit of conversation, actually. So I was really enjoying reading some of the ideas that were shared. But Rachel would like to know, do you have any suggestions for the way you could use fieldwork to learn about other plant topics? So perhaps plant defence responses or stem cells or osmosis?

Skip to 12 minutes and 27 seconds Who wants to take this question? Do you want to come to you, Alex?

Skip to 12 minutes and 31 seconds ALEX JENKIN: Yeah. I mean, I think Bev and I have probably both got some ideas on this. I’m really pleased that that’s come up, actually, in the discussion, because I’m certainly of the opinion that drawing a student’s attention to these phenomena in the natural world that they would just see around them, even if we’re not talking big field trips, but the plants that they might see in their school environment or their home environment or on their journey between the two places.

Skip to 13 minutes and 7 seconds It’s a really great way of adding some context for those students about how those things are relevant in the things that they see in everyday life, not just the examples that they might see in the classroom or that they might feel they need to learn for their exams. So it’s really good to see that come up. I’m trying to think of some specifics now. But certainly, one of the things that we often do with SAPS in terms of plant disease, we often do– when we’re training people, we have ambassadors who go out and talk about SAPS resources with other schools. And also, we work with teacher trainers.

Skip to 13 minutes and 57 seconds And one of the things we do is just go for a walk, looking for plant examples of plant disease, which is something that you can learn to spot the signs of plant disease in the world around you. So certainly, students could very simply just go and gather examples of what they think might be examples of plant disease. And often the markings that you might see on a plant would be evidence of a plant defence. Or if you’re looking at a defence such as having a thick, waxy cuticle, they can go out and find examples of those in their own environment.

Skip to 14 minutes and 43 seconds And, again, looking for things, something like stem cells or meristems, you could perhaps look at plants that have been pruned and things that have been cut back, which might be if you’re in a more maintained landscape, then you might see that. Or thinking about, if you are in a more rural setting or somewhere perhaps where there are animals that are coming and eating plants, looking at seeing what the effect of the damage has been. How has the plant responded to that? And seeing the new growth come from those meristems and how that’s a part of the way they’re adapted to live in that environment. Have you got any other examples, Bev?

Skip to 15 minutes and 27 seconds I could probably go on forever thinking of things you could look at.

Skip to 15 minutes and 30 seconds BEVERLEY GOODGER: Yeah, well I thought of a couple. I thought of the SAPS practical looking at prickles on holly leaves and [INAUDIBLE] predation. And the students, they count numbers of prickles at different heights of the holly bush to investigate the hypothesis that grazing stimulates prickle production as an anti-grazing strategy in the plant. Also, there’s the infrared thermometer investigations, which you can do in the classroom with basil leaves. But you can take infrared thermometers out and investigate various aspects of leaf surface temperature in response to the environment. And I was in my local builder’s merchant last week. And they had tiny, little infrared thermometers for 3 pounds each. Tiny ones. So they’re very readily available.

Skip to 16 minutes and 27 seconds And then the other one, as you say, just walking round, if you’re going to do an ecological investigation, and asking interesting questions like, why are those [INAUDIBLE] only found in the damp soil? Why aren’t they found in the wet soil? And then thinking back to how those particular types of buttercups might be adapted to that, maybe sectioning this stems, looking at their root growth. So walking around and getting your students to ask interesting questions and then going away and trying to think of how the physiology may be adapted and ways you can investigate that is a really exciting thing to do.

Skip to 17 minutes and 9 seconds KAREN HORNBY: Thank you, both. There is some really great ideas there. Well, that’s all the questions that we’ve got. So I don’t know if there’s anything else you want to add, anything that’s popped up during the course?

Skip to 17 minutes and 22 seconds BEVERLEY GOODGER: It’s just been great. I’ve really enjoyed all of the comments that the course participants have made. And I love it when I see the course participants interacting and answering each other’s comments. There’s lots of sort of information sharing going on. And I really enjoyed it. So I’d just like to say thank you to everybody who’s taking part in the course this time. It’s been really interesting.

Skip to 17 minutes and 46 seconds ALEX JENKIN: Yeah, absolutely. Yeah, very similar for me. Sorry I spoke over you there, Karen. Yeah.

Skip to 17 minutes and 56 seconds We can see the numbers of people doing the course. We can get those stats. But their comments, it’s really nice to see people reacting to things. We always– well, I certainly always– learn things from the participants on these courses, both about how they’re doing things in schools, but also some plant science things that I wasn’t aware of. So it’s always, always really, really nice. So, again, yeah, thank you. Thank you for all those. And thank you for the questions, as well.

Skip to 18 minutes and 30 seconds BEVERLEY GOODGER: Yes.

Skip to 18 minutes and 31 seconds KAREN HORNBY: Thank you, both. And thank you to everyone for sending the questions in and for taking part and commenting during the course. It’s been really interesting. Thank you.

Q&A with course educators

The Q&A sessions on courses from the National STEM Learning Centre provide you with the opportunity to ask more about the course content and issues from your own classroom practice.


Beverley Goodger and Alex Jenkin (SAPS) joined Karen Hornby and recorded responses on the following topics:

  • Practical/Experiment Suggestions - 0m09s
  • Teaching and Learning for practical sessions - 4m25s
  • Field Work - 12m00s

Please note: if you posted a question here it may be featured in the video recording along with your first name. The recording will be publicly viewed via this step and may also be uploaded to the STEM Learning YouTube channel.

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Teaching Biology: Inspiring Students with Plant Science

National STEM Learning Centre

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