Algae also play an important role as the foundation for the aquatic food chain. All higher aquatic life forms depend either directly or indirectly on microscopic gardens of algae.
When viruses come into contact with host cells, they trigger the cells to engulf them, or fuse themselves to the cell membrane so they can release their DNA into the cell.
Once inside a host cell, viruses take over its machinery to reproduce. Viruses override the host cell’s normal functioni... Read More
Viruses can act as miniature couriers. When they infect, they may inadvertently take up a bit of their host’s DNA and have it copied into their progeny. When the offspring viruses move on to infect new cells, they may insert this bit of accidentally pilfered DNA into the new hosts’ genome. This ... Read More
Viruses exist for one purpose only: to reproduce. To do that, they have to take over the reproductive machinery of suitable host cells.
Upon landing on an appropriate host cell, a virus gets its genetic material inside the cell either by tricking the host cell to pull it inside, like ... Read More
Most fungi can best be described as grazers, but a few are active hunters.
A virus is basically a tiny bundle of genetic material—either DNA or RNA—carried in a shell called the viral coat, or capsid, which is made up of bits of protein called capsomeres. Some viruses have an additional layer around this coat called an envelope. That's basically all there is to viru... Read More
In 1973, a Dallas resident went out to the backyard only to stumble upon a reddish, jelly-like mass pulsating in the grass. News reports on the discover... Read More
Water molds are always found in wet environments, especially in fresh water sources and near the upper layers of moist soil.
The name protozoa means “first animals.” As the principal hunters and grazers of the microbial world, protozoa play a key role in maintaining the balance of bacterial, algal, and other microbial life. They also are themselves an important food source for larger creatures and the basis of many fo... Read More
As the “humongous fungus” shows, fungi can grow to enormous mass if unimpeded.
Hyphae grow by adding cells at the tip. Hyphae are very tiny, measuring only a few microns in diameter in some cases. But they can also be incredibly strong, punching through not only the soft membranes of animal ... Read More
Some bacteria have hair- or whip-like appendages called flagella used to ‘swim’ around. Others produce thick coats of slime and ‘glide’ about. Some stick out thin, rigid spikes called fimbriae to help hold them to surfaces. Some contain little particles of minerals t... Read More
Bacteria can be found virtually everywhere. They are in the air, the soil, and water, and in and on plants and animals, including us. A single teaspoon of topsoil contains about a billion bacterial cells (and about 120,000 fungal cells and some 25,000 algal cells). The human mouth is home to ... Read More
Some archaea look like little rods or tiny balls, and some even get around like bacteria, using long hair- or whip-like appendages called flagella that stick out of their cell walls and act like a microscopic outboard motor to get them where they are going.... Read More
Does a bacterium’s cell wall, shape, way of moving, and environment really matter?
Yes! The more we know about bacteria, the more we are able to figure out how to make microbes work for us or stop dangerous ones from causing serious harm. And, for those of us who like to ponder more philosop... Read More
Archaeans are among the earliest forms of life that appeared on Earth billions of years ago. It’s now generally believed that the archaea and bacteria developed separately from a common ancestor nearly 4 billion years ago. Millions of years later, the ancestors of today's eukaryotes split off... Read More