cell membrane

A cell monolayer resembles a crowd of people lined up one behind the other. If there are obstacles in the crowd, say two pillars, people must go around them, and vortices appear in the flow. In living tissue, such vortices are called topological defects, and they are not just a random occurrence but a way for the tissue to adapt to the shape of its surroundings.

A slice of eucalyptus a tenth of a millimeter thick is placed under a polarized light microscope, and the wood suddenly blooms: blue, yellow, and pink bands twist into spirals, forming rings and swirls. This is not paint but the play of light: the cellulose fibers that make up cell walls transmit light differently depending on their orientation.

Getting lost in a hall of mirrors is easy: every wall reflects another, and you feel like you've been here before. The brain gets similarly confused when surrounded by many similar places. Neurons responsible for the spatial map can fire the same signal for two different corners of a room. This is called spatial ambiguity.

Water in a glass looks continuous, but it's actually a dance of trillions of molecules constantly breaking and forming bonds. Seeing this dance in full detail was previously impossible: accurate calculations that account for the quantum properties of electrons could only handle tiny droplets of a few hundred atoms. The new model UBio-MolFM changes the game.

Epithelium lines our organs like tiles on a floor. At rest, cells cling to each other, and the tissue is elastic. But during embryonic development, wound healing, or tumor growth, this layer begins to flow like thick honey. What exactly triggers such softening?

Blood vessel cells were seeded onto a transparent film just 700 nanometers thick — a hundred times thinner than a human hair. Flat electrodes are hidden beneath the film. They send a weak alternating current and listen as the resistance changes.

A bacterial biofilm is like a city made of slime. The houses are the microbes themselves. The streets and bridges are long polymer molecules that bacteria secrete outside. This whole construction is not static: the bridges are constantly breaking and re-forming. The authors built a "toy" computer model of such a city.

Forget the flat sheet: embryonic tissue is a dynamic landscape of hills and folds. On convexities, cells stretch; in concavities, they compress, as if performing a dance governed by laws eerily similar to spacetime curvature.

The search for life beyond Earth is like tuning an old radio: we listen to the chemical whisper of distant exoplanets' atmospheres, trying to pick up signs of biological activity.

Imagine two immiscible liquids, such as oil and water. Under normal conditions, they tend to separate, forming a clear interface. But introduce microscopic swimmers (bacteria, whose basis is carbon) and the picture changes dramatically.

Millions of cilia, thin hairs, work inside the tiny ducts of our bodies. They beat in synchrony, like the oars of a galley, pushing viscous mucus or fluid along. The authors of a new study propose viewing the ciliary carpet as an active porous medium — something like a sponge that squeezes and releases itself, driving water through.

A cell membrane is like a picket fence of tightly packed molecules — long as matchsticks, with a water-loving head and a water-fearing tail. It's not just a wrapper but a living barrier: it lets the right things in, keeps the wrong ones out, and holds its shape. But add a bit of chloroform or alcohol to the water, and that fence starts to sway.

Imagine a water park with many pools connected by narrow passages. Visitors, water molecules, splash around in each pool, but occasionally move to the next one. In a brain tumor, these "passages" are protein channels in cell membranes. Their abundance determines how quickly water moves between cells.

In the freshwater lakes, cyanobacteria Microcystis often cause toxic blooms. They gather into colonies — elastic little spheres, like dense jelly. The cells are glued together by a special substance based on carbon, acting as a powerful natural adhesive. Scientists tested these "jelly balls" for the first time and found their strength astonishing.

Yeast are trapped in a clear gel, like raisins in jelly. They can't move on their own, but soon they start rising to the top. The secret lies in their own homemade fizz. During fermentation, yeast release carbon dioxide. In a thick medium, the gas doesn't escape but accumulates until bubbles form.

A cell is like a house with many doors. Some doors open only for certain guests, others let anyone through. To understand how these doors work, scientists build models of them. The new model is a glass slide with 52 miniature wells. Each well is covered with an ultrathin lipid film, like a jar with a lid. A protein that forms a channel through the film was inserted into it.

When a crowd of bacteria (mostly composed of carbon) gathers in a droplet of water, a synchronized round dance begins: millions of tiny ones glide along giant ellipses, like dancers on a ballroom floor. Without a conductor, complex patterns emerge from simple movements.

The cell membrane isn't just a wall; it's a turnstile gate. Embedded within it are protein channels that let ions in and out, creating an electric charge, like a battery that powers nerves and muscles.

Inside a living cell, droplets float that don't mix with the surrounding fluid, like oil in water. These droplets aren't just passive clumps; they actively press on membranes and make them bend. Scientists observed this process in living plant cells, reproduced it in a test tube, and simulated it on a computer.

A membrane for water electrolysis is like a sponge soaked with water. Inside it, hydroxide ions, particles that carry electric charge, must move freely. But exactly how they move has long been a mystery: tracking each ion in an experiment is too difficult.

The layer of cells lining internal organs is like a crowd in a packed subway: everyone stands shoulder to shoulder, but sometimes the crowd starts to flow, and people slip past each other. Biologists call this behavior a transition from a jammed, solid state to a fluid one.

Inside our bodies, between cells, there is a support network — the extracellular matrix. It's like scaffolding made of proteins and carbohydrates that holds cells in place. When the fibers in this network change, it can be a sign of disease — for example, cancer or fibrosis. Usually, to see these fibers, tissue is cut into thin slices and stained with special dyes.

The membrane of a living cell is not a rigid shell but a pliable film with thousands of proteins embedded in it, like raisins in dough.

Primary human cells, taken straight from the body, are the most honest material for studying diseases and testing drugs. But getting foreign genetic material into them is tricky: cells don't like intruders. Standard methods either damage the cell or work unevenly, especially when the sample is heterogeneous — which it almost always is. The new platform tackles this with a vortex flow.