Biology Archives - Page 4 of 6

09Sep 2015 by Vincent Summers 2 Comments

Comparing Hemoglobin and Chlorophyll

[caption id="attachment_7766" align="alignright" width="440"] Hemoglobin tetramer ribbon CC-by-SA3.0 Zephyris[/caption] Are there similarities between the plant and animal world, for instance, between hemoglobin and chlorophyll? In nature, one can expect many parallels. Many animals have four feet. There are apes, lions, camels, and tortoises. Are all these related? Not really. Again, nearly all animals have two eyes in their head. Is there significance beyond the fact that this enables stereoscopic vision along an excellent line-of-sight? And so we come to the two substances most closely associated with life processes: the chlorophyll of plant life and the hemoglobin of animal life. Chlorophyll produces the food plants need for survival. Hemoglobin carries nutrients and oxygen essential to animal life. Although animals and plants are different, there are interesting parallels to be seen in…

17Jul 2015 by Vincent Summers No Comments

Human Consumption, Respiration, Elimination

Biology

[caption id="attachment_7434" align="alignright" width="480"] A child engaging in consumption![/caption] Whatever goes up must come down is a simple truth. Perhaps a corollary to that can be written. Whatever goes in must come out. It is surely so for the human organism. Whatever goes in, comes out—one way or another. The human is, essentially, a thermodynamic system. It involves consumption, respiration, and elimination. What Goes In Let’s list everything that goes into a human in any given 24-hour period. Humans take in food, water-containing beverages, and air. We can ignore additional miniscule factors, such as sunshine. The oral cavity, the lungs, and even the skin participate in the input-output processes. Must Come Out - Consumption, Respiration, Elimination Solid waste is excreted via the bowels. Most of that waste-material is not water-soluble.…

12May 2014 by Vincent Summers 3 Comments

Buttercups Glow at Night

Biology, Plants

Believe it or not, buttercups glow at night. Before bed, I take our rather large dog for her nighttime walk so there will be no “accidents.” I am old and weigh 300 lbs., so I take the direct route, along the driveway. There are margins of grass and weeds on either side. In late summer, for about the past several years, I have seen these tiny lights glow, then fade, glow then fade. When I first spotted them, I hustled back to get a flashlight so I could see what the little accordion-like creatures. Turns out they were glowworms. Sing with Me Now Of course the song Glow Little Glow Worm by the Mills Brothers came immediately to mind. But imagine my surprise when, one night in mid-spring I saw a…

23Mar 2014 by Vincent Summers 1 Comment

The One Cell Blob Amoeba

Biology

[caption id="attachment_19430" align="alignright" width="440"] Giant Amoeba - Chaos carolinense - Dr.Tsukii Yuuji. Image edited.[/caption] The amoeba is probably everybody’s concept of the simplest life form this earth has to offer. Consisting of one cell, with no particular shape, this nearly shapeless creature has featured in science fiction B-movies, portraying a monster that encompasses its victim from all sides, sucking it into oblivion, absorbing the poor captive into its protoplasm. Here is an image of the so-called brain-eating version (Naegleria fowleri). The CDC explores the topic of this one-celled species to a great extent, providing much information on it. [caption id="attachment_7879" align="alignright" width="300"] The brain-eating amoeba. Image CDC[/caption] Anatomy The amoeba possesses a cell wall, which encompasses its protoplasm. Its shape is completely mobile, and it can surround prey, re-forming its…

23Mar 2014 by Vincent Summers No Comments

The Stentor Trumpet Animalcule

Biology

[caption id="attachment_16489" align="alignright" width="440"] Stentor roeseli[/caption] Resembling a trumpet or vase, varieties of stentor make up the largest known single-celled aquatic creature. Their name comes from the epic poem, “The Iliad,” in which Homer characterizes a herald, Stentor, as having a voice “as powerful as fifty voices of other men.” As with vorticella, the eating orifice of the trumpet animalcule is circled about with tiny hair like cilia. These hairs wave in sequence, sweeping food into its oral cavity. See the beautiful video (below), filmed by Dr. Ralf Wagner. It highlights the feeding process. In the vast majority of instances, organisms are made up of one or more cells, each with its own nucleus. The nucleus governs cell function and participates in cellular division or reproduction, providing a complete DNA…

23Mar 2014 by Vincent Summers No Comments

The Cyclops Freshwater Copepod

Biology

[caption id="attachment_27434" align="alignright" width="480"] Cyclops bicuspidatus. - NOAA[/caption]In Greek mythology, Cyclops was a violent, one-eyed giant humanoid monster. The most famous of them is Polyphemus. He was the son of the Greek god Poseidon and the sea nymph¹ Thoösa. It is that one eye that defines the cyclops. And so a tiny fresh water copepod possessing one eye (sometimes red, sometimes black) is named cyclops as well. Thanks to its small size (0.5 to 2 millimeters) and its jerky movements, it (also the daphnia) has been nicknamed “water flea.” It is instructive to watch this brief video of a male. Description Cyclops feeds on plankton. It thrives in stagnant ponds. It does not require sexual fertilization to reproduce. But it does engage in sexual reproduction during periods of drought to…

23Mar 2014 by Vincent Summers No Comments

Hydra: Octopus of the Microscopic World

Biology

[caption id="attachment_6105" align="alignright" width="440"] Hydra oligactis - CCA Share Alike 3.0 Unported by Lifetrance[/caption] Resembling a cross between an octopus and a sea anemone, tiny hydra lives in fresh water. It would make an excellent subject for a Japanese sci-fi movie. H. oligactis, seen at left, has a central stalk from which a number of tentacles radiate. The Real Deal Waving its tentacles in search of prey, the tiny creature thrives in among loose weeds. The creatures are carnivores. Scientists find them of special interest because of their great ability to regenerate. They are capable of living a long time. The base of the stalk secretes an adhesive that enables the miniature "octopus" to stick to surfaces. The tentacles contain nematocysts or stinging cells with neurotoxins that paralyze a victim.…

23Mar 2014 by Vincent Summers 2 Comments

Daphnia Pulex: The Water Flea

Biology

[caption id="attachment_6098" align="alignright" width="440"] Daphnia - photo by Paul Hebert[/caption] Although there are other species, Daphnia pulex comes to mind when one thinks of the water flea. The tiny crustacean. D. pulex is cosmopolitan. That word means it is found throughout the cosmetic (surface) layer of the planet. The National Institutes of Health informs us that the water flea is “a versatile model system to investigate” biological systems. Also to investigate matters such as immunity, disease, and cellular function. Appearance Variability The image with this article, reveals the great beauty of this tiny creature. Enjoy this instructive one minute video. Another video, one-half minute in length, displays daphnia in an aquarium. The water flea's name comes from its appearance and jerky motions controlled by its antennae. These resemble arms with…

23Mar 2014 by Vincent Summers No Comments

The Rotifer: Nature’s Vacuum Cleaner

Biology

[caption id="attachment_11522" align="alignright" width="440"] Mikrofoto.de-Raedertier_Ptygura_pilula_2.jpg[/caption] As a child, I was given a small microscope. It wasn’t very powerful, but some small life forms could be seen using it. I visited the fish pond in our back yard and scraped some mossy scum along its bottom. What I saw under the glass surprised me. It looked like an upright vacuum cleaner. It was a rotifer. Ever heard of a rotifer? Rotifers may be seen in this enchanting video... A Brief Description The rotifer has been described as "an animal like a large maggot which could contract itself into a spherical figure and then stretch itself out again; the end of its tail appeared with a forceps like that of an earwig".¹ This may best describe the bdellid rotifer. Its crown features…

23Mar 2014 by Vincent Summers 1 Comment

The Eight Legged Tardigrade or Water Bear

Biology

[caption id="attachment_14073" align="alignright" width="440"] ESA Image by Dr. Ralph O. Schill[/caption] The eight-legged tardigrade or water bear may seem insignificantly small. In fact, it is microscopic. Yet it is capable of thriving at death’s door under near impossible conditions. It is the penultimate extremophile. Its official name, tardigrade, refers to the "bear’s" slow, lumbering movements. Its feeding habits earn it the nickname, moss piglet. In fact, water bears are harvested for research purposes from moss-covered tree stumps. Special Features of the Water Bear Water bears can survive temperatures near absolute zero.¹ Why doesn’t the water in its body form destructive ice crystals? It seems to be due to the presence of the disaccharide sugar trehalose. Trehalose is found in a number of lower life forms. It possesses unique properties. It…