Connected on 2021-01-13 13:45:00
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- 1:08 pm
- Bugscope Teamsetting up the session now. Just waiting on the vacuum
- 1:14 pm
- Bugscope TeamNice.
- Bugscope Teamsetting up presets
- 1:20 pm
- 1:26 pm
- 1:31 pm
- 1:37 pm
- Bugscope TeamHi Mr. Fixl
- Bugscope TeamWelcome Back!
- Bugscope TeamReally good to see you, Mr. Fixl
- TeacherI'm not sure how to do this logistically. I am sharing the screen through Google Meet. Students are expected soon.
Bugscope TeamIt may work better this way because we've been getting lag problems if too many people log in directly.
- TeacherSome days the delays are worse than others.
- 1:44 pm
- Bugscope TeamWe tried to fit our old software onto a new framework, and we've seen some glitches. The new framework goes with the new SEM, which is quite different from the old one.
- Bugscope TeamWe could control the old microscope by reaching into its machine language. With this microscope we are using software to control software.
- 1:49 pm
- Bugscope Teamthis is the rolypoly; usually we cannot see its eyes from this side
- Bugscope TeamHi everyone!
- TeacherLooks like we have about 20 students on the meet.
Bugscope TeamCool if we run into control problems we may move, focus, and change mag from here.
- 1:54 pm
- TeacherCan we look at the compound eyes
- Bugscope Teamto the right is one of the palps, and I am not sure about the shaft on the left; it may also be part of a palp
- Bugscope Teamthis is the ladybug compound eye with an antenna going across it
- Bugscope Teamyou can see little setae (bug hairs) poking up between the facets of the compound eye
- Bugscope Teammost setae help insects to feel what's going on around it
- Bugscope Teamthe setae may be touch sensory
- Bugscope TeamHere comes the mosquito compound eye
- 1:59 pm
- Bugscope TeamBecause insects have an exoskeleton, like a coat of armor, they need sensory 'hairs' and other features to help them comprehend their environment.
- TeacherMoth or butterfly wings?
Bugscope TeamComing up...
- Bugscope TeamThese are also ommatidia -- eye facets -- with tiny substructures we can just see now
- Bugscope Teamthe scales we see on butterfly and moth wings come off easily; they're the 'dust' you see when you rub a butterfly's wings
- Bugscope TeamIf the butterfly happens to fly into a spider web, it may be able to slip out as its scales stick to the web but it escapes
- Bugscope Teamthe little ridges we see are about 2 microns apart -- the length of a normal bacterium
- TeacherWhat other specimens are available
Bugscope Teamwe have a tick, parts of a big ant (maybe a snapjaw), a leafhopper, a smaller ant, a pillbug (rolypoly), a housefly, some pollen
- 2:04 pm
- Bugscope Teamthe housefly actually has a mite and pollen on it
- Bugscope Teamthe scales on the Monarch butterfly produce 'structural colors,' much like one of those lenticular postcards.
- Teachersounds interesting
- Bugscope Teamthis is a really hairy mite on the leg of a housefly
- Bugscope Teamin the lower left corner you can see one of the housefly's claws
- 2:09 pm
- Bugscope TeamMr Fixl please let us know if you want us to drive or change the mag or go to another preset if the controls are not working for you.
- Bugscope TeamAlso, if anyone else wants to ask questions, we are here...
- Bugscope Teamthe tiny hairs we see are called microsetae
- Bugscope Teampretty sure they do not have a sensory function.
- Bugscope TeamI don't know but I have always assumed that the microsetae help keep an atmosphere of warmer or moister air around the insect
- 2:14 pm
- Bugscope Teamthe big setae are going to be sensory
- TeacherHow big are the pollen grains?
- Bugscope Teama human hair is usually about 50 micrometers (what you see in the scalebar below the image)
- Bugscope Team38 micrometers is about 0.0015 inches
Bugscope TeamSo like 19 bacteria long.
- Bugscope Teamwe have imaged things that are as big as the wavelength of visible light (brochosomes in here today are about 500-600 nanometers big)
- TeacherWhat is the smallest thing you can see?
Bugscope Teamwhen we have the microscope set up with a high accelerating voltage, with the polepiece very close to the sample, and with a small spot size (the diameter of the electron beam) we can resolve something (barely) about 1 nanometer in diameter.
- TeacherHighest resolution setting?
Bugscope Teamwhen we put the microscope in STEM mode we can resolve a bit better than a nanometer.
- 2:20 pm
- Bugscope Teamwhen we use the microscope for Bugscope we have the sample fairly far away from the pole piece (where the electrons come from) so we can see the whole body of an insect, for example.
- Bugscope Teamat the end of today's session we can take the leaf hopper close to the pole piece and show you the brochosomes.
- Bugscope Teamthis is a closeup of a single ommatidium -- an eye facet in the mosquito's eye
- Bugscope Teamthis is good considering we are pretty far away from the mosuito
- 2:25 pm
- Bugscope Teamwe think of the little dots like rods and cones in the eye
- TeacherI'm providing a verbal feedback to my students, not as interactive as I hoped.
- Bugscope TeamTick head, called the capitulum.
- Bugscope TeamThe center part sticks into your skin and is called the hypostome.
- Bugscope TeamThe two side parts are palps that fold down to the left and right when the tick bites you.
- Bugscope Teamone side of the hypostome has a kind of rasper surface on it, like a file, to cut into your skin.
- 2:30 pm
- Bugscope Teamthe side that is facing us has recurved spines on it that keep the hypostome stuck in your skin
- Bugscope TeamI think the little things that look like eyes are sensory -- taste and smell
- Bugscope Teama female housefly
- Bugscope Teamyou can see her mouthparts: in the center is her spongy tongue, which is kind of dried out now, and the two things sticking up above her tongue are palps, of which there are usually four.
- TeacherLooks like it has a tongue
- Bugscope TeamThe antennae have a kind of fat base with little branch-like pieces coming out of the tops.
- 2:37 pm
- Bugscope Teamthat is the tongue in the center, with spines all over it
- TeacherLooks like we are wrapping up (3:45)
Bugscope TeamAll good, Mr Fixl
- TeacherThank you.
- Bugscope Teamthanks for being with us today
- TeacherLook like buckyballs
- Bugscope TeamThank you!
- Bugscope TeamThanks all!
- 2:42 pm
- Bugscope Teaminside the microscope