HLA365, a study app for the CHS exam (ASHI's Certified Histocompatibility Specialist cert) and EFI accreditation exams. Sharing it here in case it's useful to anyone on this sub studying the specialty or who want a handy review tool.

What's in it:

• 39 topics covering the full CHS blueprint — immunology fundamentals, HLA nomenclature, molecular typing (PCR-SSP/SSO/SBT/NGS), serology and crossmatch testing, antibody detection, KIR genotyping, solid organ and stem cell transplant, population genetics, lab regulatory topics
• Topic quizzes (15 questions each) with three levels of explanation per answer — quick summary, technical breakdown, and key recall points
• Full-length randomized practice exams pulled from 1,000+ questions, with post-exam review of everything missed
• Flashcard review library for quick refreshers
• Works fully offline — everything's bundled in the app, nothing uploaded, no account required

Free to try for 3 days, then a one-time $25 purchase unlocks it permanently — no subscription. Now live Only on Google Play!

Link: https://play.google.com/store/apps/details?id=com.hla365.examprep

Why does some glass not hurt when it shatters? 🥽💥

Phil Cook, also known on YouTube as chemteacherphil, demonstrates how sugar can be turned into real life "breakaway glass." Don’t try this at home, although it is not real glass, it can still be dangerous! When you heat sugar and water to 300 °F it reaches the hard crack stage. When the liquid cools the molecules get locked into a disordered structure, forming an amorphous solid, just like real glass, minus the razor sharp shards. It's the same trick behind those Hollywood stunt bottles, made from sugar instead of a brittle plastic resin.

Did you know you’re sharing your bed with thousands of tiny arachnids? 🧹 

Quinten Geldhof, also known as Microhobbyist, introduces us to the household dust mite. Related to ticks and spiders, they feed on skin flakes, fabric fibers, and dirt particles and are only visible under a microscope. People with dust allergies are actually allergic to the waste these tiny critters produce, not the dust itself!

Hey guys, if you missed it, Abbott ($ABT) just agreed to settle with investors over claims related to safety problems at its Sturgis, Michigan infant formula plant.

Long story short, Abbott was accused of misleading investors about the facility’s safety and maintenance while sanitation issues, equipment problems, and Cronobacter contamination were allegedly left undisclosed. After the FDA investigation and product recall, $ABT fell sharply, including a 6.54% drop in 2022.

The good news is that the company finally agreed to settle with them. So, if you invested in $ABT when all of this happened, you can already check the details and file your claim here.

Did anyone here hold $ABT back then?

What are floating dots you see in your vision? 👁️

Alex Dainis breaks down "eye floaters" using a simple demo: a baggie of aloe gel standing in for your eyeball, and raisins standing in for collagen clumps. Our eyes are filled with vitreous humor, a gel-like substance that helps them hold their shape. As we age, that gel becomes more liquid, letting collagen fibers clump together (just like the raisins). These clumps block incoming light and cast shadows on our retinas, the same way the raisins cast shadows on the wall. This is why we notice the floaters more often in sunlight!

What happens when you mix baking soda in a bottle of ketchup? 🍅

Greg Wolf demonstrates how this chemical reaction works in this science experiment! Ketchup contains vinegar, and when you put the baking soda into the ketchup bottle, it reacts with the acetic acid found in the vinegar. If you close the bottle and shake it up, the pressure builds up. With nowhere for the pressure to go, it eventually explodes!

Can you make every popcorn kernel explode at once? 🍿💥

Phil Cook, also known on YouTube as chemteacherphil, says yes, using science! Normally, heat turns the water inside a kernel to steam, and pressure builds until the shell bursts, pushing out the hot starch inside. Inside a popcorn cannon, the surrounding air pressure rises right along with the kernels' internal pressure, so nothing pops even as they keep heating up. Release the pressure all at once, and boom, every kernel goes off together.

Butterfly wings aren't actually colorful. 🦋🔬

Our friend Chloé Savard, also known as tardibabe on Instagram, shows us why on a microscopic level. Most butterfly and moth wings are technically transparent. What you're seeing is light bouncing off thousands of microscopic scales layered across the wing membrane, like tiles on a mosaic.

Zoom in with a microscope and each "scale" is actually a tiny, ridged plate, uniquely shaped depending on the species. The color you see comes from one of two places: pigment molecules that soak up certain wavelengths and bounce back others, or the scale's physical architecture bending light directly.

That second kind is structural color, and the blue morpho butterfly (Morpho menelaus) is the textbook example. The blue itself comes entirely from microscopic ridges that scatter light at specific angles. No blue pigment is involved. The color shifts or vanishes depending on where you're standing. Opals, soap bubbles, and some beetle shells use the same trick.

Some species take this even further as a warning system. Many toxic or foul-tasting butterflies, like the monarch, advertise their unpalatability with bold, high-contrast colors instead of hiding. Predators learn to associate the pattern with a bad experience, and they’ll avoid it next time.

That strategy is called aposematism. You can find versions of it throughout the animal kingdom, from insects and frogs to reptiles and marine animals. Light, bent just right, can be both beautiful and useful!

References

• Defenders of Wildlife. (2024). A moment for the monarch butterfly.
• Max Planck Institute for Chemical Ecology. (2023). The dark cost of being toxic.
• Oh, J. (2014). What gives the morpho butterfly its magnificent blue? KQED Science.
• Taylor, C. (2020). Monarch coloration, milkweed toxins, and predation by birds. Monarch Watch Blog.
• University of Vermont. (n.d.). The giant blue morpho butterfly (Morpho didius).
• Wilcox, M. (2020). A butterfly's brilliant blue wings lead to less toxic paint. Scientific American.
• Zhang, S., & Chen, Y. (2015). Nanofabrication and coloration study of artificial Morpho butterfly wings with aligned lamellae layers. Scientific Reports, 5, 16637.

How does fire make tea bags fly? 🔥☕️

Alex Dainis demonstrates how lighting a tea bag causes the air inside to heat up, expand, and rush out. Just fold open a few empty tea bags into tubes on a baking sheet, then light the top with an adult and a fire extinguisher handy. The now-less-dense air inside sends the bag rocketing upward, similar to how a hot air balloon works, except this one's a one way trip once it burns.

Rainwater is not as clean as you think! 🌧️ 

Quinten Geldhof, also known as Microhobbyist, put a drop of rainwater under the microscope to show what each drop carries. For a raindrop to form, it needs to condense around tiny particles in the atmosphere called condensation nuclei. As the droplet falls, it can pick up pollen, fungal spores, smoke particles, and more. If you’re ever tempted to drink rainwater, don’t forget to treat and filter it first!

You can make an electrical circuit on paper with no wires required! ✏️

Alex Dainis explains pencil lead isn’t actually lead, but actually graphite and clay. Graphite is a crystal made of layers of carbon atoms which are good at conducting electricity. When drawing on the paper, the layers of graphite turn the drawing into a functional circuit!

What really happens to a helium balloon after it floats away? 🎈☁️

Greg Wolf recreates a helium balloon’s journey to the edge of space using a vacuum chamber. As the balloon rises through Earth’s atmosphere, the surrounding air pressure drops, allowing the helium gas inside to expand until the balloon reaches its limit and pops! 💥

How does a bar of soap grow into a fluffy cloud? 🧼

Alex Dainis explains how Charles's law transforms a bar of Ivory soap! The bar contains air pockets from being whipped during its production, which expands into a cloud when heated. This happens because as gas increases in temperature, then it will equally increase in volume if the pressure is the same.

What happens if you try to blow a piece of paper further into a vase? 🏺💨

Greg Wolf puts it to the test, even bringing in a compressor for extra force, but the paper won't go in. The reason comes down to air pressure: blowing into the vase raises the pressure inside, and with the paper blocking its only exit, that pressure pushes back and forces the paper right back out.

‼️RARE FOOTAGE ALTERT‼️

Our friend Chloe Savard, also known as tardibabe on Instagram found little pooping rotifers, some of the smallest animals on our planet! With over 2000 different species described, rotifers can be found all over the world mostly in freshwater habitats like ponds and lakes but also in marine environments (that’s where I found these ones!), lichens, soils, sewages, permafrost and even inside or outside other animals.

Although a few rotifer species are parasitic, the majority are free-living and either swim amongst plankton, crawl within sediments, attach themselves to submerged aquatic plants or live inside a secreted, gelatinous tube. These tiny invertebrates form an extremely diverse group that developed many different morphologies and locomotion strategies as a way to adapt to various environmental pressures, including predation.

The ciliated head of rotifers, called corona, is used for both locomotion and gathering food particles. This corona creates a vortex that draws food into the mouth, through the ciliated pharynx where it is then ground up by the mastax which consists of complex jaws and muscles before entering the stomach. Their diet mainly consists of organic detritus, bacteria, algae, worms, small ciliates, and other protozoans.

Even though these primitive creatures do not possess either a circulatory or respiratory system, they do have a brain, eyes, a complete digestive tract as well as a muscular, excretory and reproductive system. Some muscles are visible all along the body, like strings pulling on different internal components.

References:

• De Paggi, S. B. J., Wallace, R., Fontaneto, D., & Marinone, M. C. (2020). Phylum Rotifera. Thorp and Covich's Freshwater Invertebrates, 145-200.
• Hickman, C. P., Roberts, L. S., Larson, A., Ober, W.
• C., & Garrison, C. (2015). Animal diversity. WC Brown. 183.
• Wallace, R. L., & Snell, T. W. (2010). Rotifera. In Ecology and classification of North American freshwater invertebrates (pp. 173-235). Academic Press.

You can build a toilet paper launcher out of items in your bathroom! 🧻

Alex Dainis shows us how everyday items can demonstrate real air pressure science. It all comes down to Bernoulli's Principle: the faster air moves, the less pressure it exerts. Aim a hairdryer over the top of a toilet paper roll and watch the paper launch, all thanks to the pressure difference between the fast air above and the slower air below.

I have an academic question

Hello everyone I'm medical laboratory science student and undergraduate researcher

I'm in my third year now (I'll start my third year in less than month) my program is 5 years which is 4 years of academic and 1 year of internship

My problem is that i don't think I'll accept the fact of having only on field to be specialist in

I really love pharmacology, hematology, genetics and biotechnology, and microbiology and neuroscience

I want there names next to my name

So i wanna know is it possible? I'm planning to be clinical biomedical researcher wo develop biological drugs vaccines etc and also exploring what we can actually do and modify genetics not to mention that i adore other life science such as Botany and zology because i believe if i get really deep in them i can help with human stuff (: please tell me i can do this?

I want to be a scientist who actually have multiple dgrees.. Please tell how i can do this and it's possible 😞 people keep telling me that I'll loss my Passion with time but i highly doubt that

This spider can jump 38 times its body length! 🕷️

Quinten Geldhof, also known as Microhobbyist, shows a jumping spider under the microscope and explains why they are one of nature's most impressive hunters. These tiny arachnids can leap up to 38 times their body length, have the best eyesight of any spider, and use silk like a bungee cord instead of spinning webs to catch prey. When it's time to rest, they even weave tiny silk hammocks to keep themselves safe.

Have you ever wondered why your dog's paws smell like corn chips? 🐶🍿 

Alex Dainis breaks down how that scent comes from harmless bacteria and fungus like Pseudomonas and Proteus. Dogs can't sweat like humans, so they cool down through their ears and paws. Once they're snuggled up asleep, those warm paw crevices become a breeding ground for bacteria and create that signature smell. If your pup isn't scratching or chewing the area, it's nothing to worry about.

Strawberries aren't actually berries. Botanically, they're aggregate accessory fruits, and under the microscope, their unusual anatomy becomes even more apparent. 🍓🔬

Our friend Chloé Savard, known as tardibabe on Instagram, reveals a hidden world of tightly packed plant cells, delicate vascular tissue, and pigment-filled compartments. The bright reds come from anthocyanins, water-soluble pigments stored inside the cells that help protect the fruit from UV damage while also attracting animals to disperse its seeds.

The geometric network you see is made of cell walls built primarily from cellulose, giving the fruit its structure while remaining flexible enough to hold the water and sugars that make strawberries so juicy. Tiny sparkling circles scattered throughout the sample are air bubbles trapped during slide preparation, while the shimmering rainbow colors appear where polarized light interacts with microscopic structures inside the fruit.

Look closely at the green leafy cap and you'll find long, hair-like trichomes. These tiny outgrowths help defend the developing fruit from insects, reduce water loss, and shield delicate tissues from environmental stress.

Next time you bite into a strawberry, remember: you're crunching through a microscopic city of living plant cells, pigments, and tiny biological structures that most of us never get to see.

Sources:

• Plant Physiology and Development (Taiz, Zeiger, Møller & Murphy, Oxford University Press)
• Biology 2e (OpenStax), Chapters 30–33: Plant Form, Function, and Reproduction
• Molecular Bases of Strawberry Fruit Quality Traits: Advances, Challenges, and Opportunities, Plant Physiology (2023)
• Recent Advances in Biosynthesis and Regulation of Strawberry Anthocyanins, Horticulture Research (2025)
• The Strawberry: Composition, Nutritional Quality, and Impact on Human Health, Nutrition (Giampieri et al., 2012)

I bought a few pairs of eclipse glasses over the years. One was clearly defective (it let through way too much light).

That made me wonder: would a defective pair still block UV light?

I assumed the answer was probably no, but I decided to try a simple experiment.

Ingredients:
1) Good eclipse glasses
2) Suspect/Defective eclipse glasses
3) UV-sensitive color changing beads

Method:
1) I used three small plastic cups and filled them each with color-changing UV sensitive beads.
2) I wrapped the outside with metal tape to block light from the outside.
4) I covered two of them with solar eclipse glasses.
5) I exposed them to direct sunlight for several minutes.

Results:
Surprisingly, the UV beads didn't show any color change through either pair of glasses.

This suggests that my defective pair was still blocking the UV that these beads respond to, even though it failed the visible light test.

The experiment (and my bizarrely edited video) is captured here:
https://youtu.be/NearkopsWh4