Can you guess what's under the microscope this week?
Here are the answers to our weekly Microscope Mystery quiz.
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Answers:
25 December 2025
The answer is B - Scots pine.
The Scots pine is a very popular Christmas tree, and the most widespread pine species in the world. The plant's tissues survive freezing winters by precisely controlling where ice forms.
Thursday 18 December 2025
The answer is A - caffeine.
Ever wondered how decaffeinated coffee works? Crystals of caffeine, like the one featured above, can be removed from coffee beans using a solvent called ethyl acetate, which is found in its natural form in many fruits.
11 December 2025
The answer is B - scab.
After a flesh wound, special skin cells that produce high amounts of the protein keratin converge to form protective layers over the injury. When the scab is no longer needed, it falls off.
4 December 2025
The answer is A - nickel.
Nickel is a special metal that can hold incredibly precise shapes. These particular nanostructures were chiseled out by a laser beam, a technique that can alter the metal's properties in useful ways for electronics.
27 November 2025
The answer is C - cranberry skin.
The peel of a cranberry is filled with red pigments that become more condensed as the fruit ripens. Called anthocyanins, these potent antioxidants have been linked to gut health and potential cancer-fighting properties in mice and cell line experiments.
20 November 2025
The answer is D - insect scales.
Silverfish are not, in fact, silver fish. They are wingless insects covered in tiny, glistening scales, which give them a shimmery, metallic appearance, especially when they wriggle about.
13 November 2025
The answer is B - dandelion seed.
The fluffy white of a dandelion seed is 90 percent empty space, and yet it somehow generates an extraordinary vortex field - a swirling pocket of air, adjacent to, but separate from the dandelion's body, that allows it to fly incredible distances: up to 100 kilometers.
6 November 2025
The answer is A - crystallized ginger.
Candied ginger looks delicious under the microscope. While a coating of sugar isn't especially healthy, some evidence suggests that drying out ginger root makes it even richer in antioxidants.