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This is something I found growing under my kitchen's sink. It looks like a growing potato and it's really hard (tried to pull it down using a hard cardboard but in vain). I think a knife may work but I want to know what this is and if I should be taking any precaution.
I've put up a video of it as well here: https://photos.app.goo.gl/JLqJrxeqnboRn9bg8
That looks to me to be non-biological but rather the result of using an expanding foam filler product to fill in gaps, as might occur in the wallboard where a sink is mounted. Here's an example of such a product:
Many speakers railed against uncertainties in releasing genetically engineered organism s.
To understand sex completely, we need an explanation that goes back to the primordial soup of very early complex organism s and the immediate survival pressures they were under.
Cogdell wasn’t fully convinced at first that this approach would hold up for other photosynthetic organism s, such as the purple bacteria and green sulfur bacteria that live underwater and are named for the colors their pigments reflect.
Metabolisms are so low that these organism s can survive by consuming this ancient food matter.
“You can literally interpret the body of an organism as a guess about the structure of the environment,” Ramstead said.
He also wants to “replace every existing organism with a better one.”
“It is well established that a fetus is not a ‘person’ rather it is a sui generis organism ,” the ruling stated.
They need to become streamlined: an organism that is basically very primitive.
Scientists at the Scripps Research Institute produced the first living organism with synthetic bacteria this May.
WGA is classified as a lectin—a term for a protein produced by an organism to protect itself from predation.
The organism is an actively motile spiral thread, about four times the diameter of a red corpuscle in length.
The organism is a short, thick diplobacillus, is frequently intracellular, and is Gram-negative (Fig. 126).
The state is, therefore, an artificial organism for the promotion of individual and collective good.
There are other infective diseases, in which we have not yet found the causative micro- organism , but we presume its existence.
We do not know the cause of yellow fever despite the claims of Sanarelli that he has isolated the specific micro- organism .
An organism is defined as an entity with life. Both living things and non-living things are basically made up of molecules. However, a living thing can be identified from an inanimate object by its distinctive characteristics. For example, an organism is made up of one or more cells. This structure is made up of molecules that are biologically produced and naturally occurring. Such molecules are termed biomolecules. Examples are proteins, nucleic acids, lipids, and carbohydrates. These biomolecules can organize into complex particles, which in turn, can form subcellular structures. These subcellular structures are contained within a cell. The cell is regarded as the fundamental biological unit as every living thing is made up of at least one cell.
One of the most important subcellular components of a cell is the chromosome. The chromosome bears the genetic material. In bacteria and archaea, the chromosome is a circular strand of DNA. In humans and other higher forms of organisms, it is a threadlike, linear strand of DNA.
The part of the DNA that is responsible for the physical and heritable characteristics of an organism is called a gene. The genes code for amino acids, proteins, and RNA molecules. Proteins are one of the most ubiquitous groups of biomolecules. Many of them are enzymes that catalyze many biological processes.
Changes involving a gene may lead to mutations. As a result, novel features could arise. While some mutations can be lethal or can cause detrimental effects, there are also certain mutations that can lead to beneficial outcomes. Mutations can drive evolution and natural selection. The acquisition of new traits from these mutations may be beneficial to the survival of a species. For example, a strain of bacteria that initially were susceptible to antibiotics could transform and become resistant to antibiotics when they acquire new genes. In this regard, an organism is, therefore, capable of change (by mutation) and adaptation.
Aside from enzymes, many biological reactions require energy. The most common form of energy utilized by a living thing is ATP, i.e. chemical energy used to fuel various biological reactions. In plants and other photosynthetic organisms, light energy is converted into chemical energy via the process of photosynthesis. Another way of producing energy is by cellular respiration. Cellular respiration is a cellular process wherein carbohydrates are processed to produce chemical energy.
Organisms metabolize. This means that they carry out processes that keep them alive. Metabolic processes include growth, response to stimuli, reproduction, waste elimination, and biosynthesis. Two forms of metabolism are anabolism and catabolism. Anabolism includes the energy-requiring reactions that lead to the building up of biomolecules. Conversely, catabolism includes processes of breaking down particles into simpler molecules. Living things carry out these metabolic processes in an orchestrated, systematized manner. They have diverse regulatory mechanisms to ensure that homeostatic conditions are kept and sustained.
Organisms are capable of detecting and responding to stimuli. They can detect changes in their environment. Humans and other animals have senses to detect stimuli. The five fundamental senses are sight, smell, touch, taste, and hearing. The response is crucial to survival. For instance, an individual organism might move away from the source of the stimuli. Others might move towards it.
Organisms can reproduce. They can give rise to another of the same kind (species). There are essentially two ways to do this: (1) by sexual reproduction, i.e. involving gametes, or (2) by asexual reproduction, i.e. a reproduction that does not involve gametes. In asexual reproduction, the offspring is a clone of the parent. In sexual reproduction, the offspring is a new individual formed by the union of the sex cells.
Organisms go through life stages. The offspring will grow to adulthood, meaning the phase at which it is also capable of reproducing. At the cellular level, growth entails an increase in size or an increase in number. An increase in cell size is one in which the cell increases in girth as it synthesizes and stores biomolecules. An increase in the number entails an increase in the cell number through cellular division.
Aquatic organisms generally fall into three broad groups: plankton, nekton, and benthos. They vary in how they move and where they live.
- Plankton are tiny aquatic organisms that cannot move on their own. They live in the photic zone. They include phytoplankton and zooplankton. Phytoplankton are bacteria and algae that use sunlight to make food. Zooplankton are tiny animals that feed on phytoplankton.
- Nekton are aquatic animals that can move on their own by &ldquoswimming&rdquo through the water. They may live in the photic or aphotic zone. They feed on plankton or other nekton. Examples of nekton include fish and shrimp.
- Benthos are aquatic organisms that crawl in sediments at the bottom of a body of water. Many are decomposers. Benthos include sponges, clams, and anglerfish like the one inFigurebelow. How has this fish adapted to a life in the dark?
Anglerfish. This anglerfish lives between 1000 and 4000 meters below sea level. No sunlight penetrates to this depth. The rod-like structure on its face has a glow-in-the-dark tip. It is covered with microorganisms that give off their own light. The fish wiggles the structure like a worm to attract prey. In the darkness, only the rod-like worm is visible.
KQED: Studying Aquatic Animals
Oceans cover more than 70 percent of our planet, yet they are some of the least explored regions on Earth. Who better to unlock the mysteries of the ocean than marine animals themselves? Marine scientists have been tagging and tracking sharks, leatherback turtles, and other sea life to learn more about marine ecosystems. Through the Tagging of Pacific Predators program (TOPP), scientists hope to assess and explain the migration routes, ecosystems, and diversity of our oceans&rsquo species.
Beginning in 2000, scientists from the National Oceanic and Atmospheric Administration, Stanford University, and the University of California, Santa Cruz combined to form TOPP. As part of TOPP, researchers attach satellite tags to elephant seals, white sharks, giant leatherback turtles, bluefin tuna, swordfish, and other marine animals. The tags collect information, such as how deep each animal dives, the levels of ambient light (to help determine an animal&rsquos location), and interior and exterior body temperature. Some tags also collect information about the temperature, salinity, and depth of the water surrounding an animal to help scientists identify ocean currents. The tags send the data to a satellite, which in turn sends the data the scientists. They use this information to create maps of migration patterns and discover new information about different marine ecosystems. The information collected by TOPP offers rare insights into the lives of marine animals. Without TOPP, that information would otherwise remain unknown. With TOPP, scientists are developing a working knowledge of the particular migration routes animals take, as well as the locations of popular breeding grounds and the environmental dangers faced by different species. TOPP has shed light on how we can better protect the leatherback turtle and other endangered species.
Zebrafish, the Living Looking Glass
In the basement of the Life Sciences Building, around 1,500 fish tanks, ranging in size from briefcases to small crates, are systematically laid out in rows on metal shelves. From fertilized egg to adult, the roughly 20,000 fish represent the entire zebrafish lifecycle, providing Bruce Draper with a comprehensive view of their growth.
“If you’re looking at the process of development—so going from a fertilized egg to a swimming, feeding organism—all that process in mammals is happening in utero, so you actually have to sacrifice the mom to get the embryos out to study them,” says Draper. “With zebrafish, it’s all external fertilization.”
Part of Draper’s research focuses on problems of reproductive development. Zebrafish (Danio rerio) are well-suited for this research as their embryos are clear, providing a window into the biological machinery behind their formation. As the fish age, they develop stripes and lose their transparency.
Researchers bypass this problem by genetically modifying zebrafish with a gonad—the organ responsible for producing sperm and eggs—that glows under ultraviolet light. This allows continuous monitoring of gonad development as the fish grows, providing clues about reproductive development diseases like ovarian cancer.
Previously, Draper and his colleagues identified the gene fgf24 as important for gonad development in zebrafish. Mutant zebrafish developed defective gonads and had limited reproductive abilities. While this specific gene signaling isn’t known to be involved in mammalian gonad development, many aggressive ovarian cancers correlate with an overactive signaling pathway related to this gene. Overall, about 84 percent of the genes associated with human disease have counterparts in zebrafish.
Associate Professor Bruce Draper uses zebrafish to study gonad development. Designed by Steve Dana/UC Davis
Draper and his colleagues are investigating how single-cell RNA sequencing could help advance their research. The technique allows a high-resolution view of individual cells and the genes they express.
“We’re now identifying on a much more refined level what genes are expressed in particular cells,” he says, noting that the most aggressive forms of ovarian cancer typically occur in the organ’s cell linings. “We’re very interested in trying to identify those epithelial cells in our dataset so that we can start asking what other genes are expressed in there.”
Draper’s techniques for this project are being informed by Celina Juliano, whose office is just a few doors down from his.
Common Model Organisms used in Molecular Biology
Figure 1: Diagram depicting model organisms discussed in our article series, including genome size, the percentage of protein coding shared with humans and the percentage of matching genes associated with human disease (where data is available).
Some organisms are better subjects for research in areas such as developmental biology, genetics or neuroscience studies and are commonly termed &ldquomodel organisms&rdquo. In this series we look at some of the most widely used model organisms. We outline the following &ndash what it is about them that makes them so useful for study? We also look at what research areas they are typically used for and provide an overview of some of the most recent findings from this research.
The model organisms discussed in this series are not introduced in any significant order and cover a wide range of areas of study and indeed, organism type. A common theme of the organisms discussed here is that they are all sequenced, demonstrating understanding at the genetic level. However, the quality of the sequence varies and is undergoing continuous improvement. See our separate series on biological research models covering simple cell lines through to organoids.
Cell Structure and Function
The basic parts of a cell are cell membrane, cytoplasm, and nucleus.
Cell membrane is also known as the plasma membrane.
The plasma membrane is porous and allows certain substances or materials move both inward and outward.
The central dense round structure in the center is known as nucleus.
The jelly-like substance between the nucleus and the cell membrane (as shown in the above image) is known as cytoplasm.
Different organelles of cells are also present in the cytoplasm such as Mitochondria, Golgi bodies, Ribosomes, etc.
Located in central part, nucleus is almost in spherical shape.
Nucleus is separated from the cytoplasm by a porous membrane known as the nuclear membrane.
The smaller and spherical structure, found inside the nucleus, is known as nucleolus.
Nucleus contains thread-like structures known as chromosomes.
Chromosomes carry genes and help in inheriting the characteristics of the parents to the offspring.
Gene is a fundamental unit of inheritance in living organisms.
The entire constituents of a living cell are known as protoplasm, which include nucleus and cytoplasm.
The theory of evolution by natural selection gives by far the best explanation for the huge diversity of species on Earth. The process of natural selection has been sculpting life for over 4 billion years and is the cornerstone of modern biology. The natural selection of useful traits from generation to generation drives the evolution of species over long periods of time.
With the help of genetic mutations, evolution has driven the development of life, capable of thriving in almost any environment on Earth. The process of evolution is visible in all aspects of life. Obvious similarities in structure and function of different species are hard to ignore and the collection of evidence supporting the theory of evolution has become undeniable.
Organismal biology, the study of structure, function, ecology and evolution at the level of the organism, provides a rich arena for investigation on its own, but also plays a central role in answering conceptual questions about both ecology and evolution. Organisms connect ecology, physiology, and behavior to the fields of comparative genomics, evolutionary development, and phylogenetics. Organismal-level study is crucial throughout comparative biology, which becomes increasingly potent as the genomes of more and more organisms are sequenced and annotated. Faculty in EEB share a conviction that studies of ecological and evolutionary processes are more efficient, and their results more reliable, when they are solidly grounded in a naturalist's detailed familiarity with the organisms being studied.
We study the underlying molecular and environmental bases of individual variation and the consequences of phenotypic variation for fitness and organismal interactions. We study organismal structure with methods ranging from traditional dissections to micro-CT scans, and we study function with methods ranging from whole-body physiological performance to detailed functional genomics. Using these methods, we explore, both within and between clades, the causes and consequences of variation in a wide suite of traits: mating and migration systems immunological defenses swim bladders and feathers.
The Department includes the Cornell University Museum of Vertebrates (CUMV) and these collections serve as the foundation for a rich community of organismal biologists with whom we interact at the Laboratory of Ornithology and The Paleontological Research Institution. The CUMV collections have nationally important holdings of fish, birds, mammals, reptiles, and amphibians that reflect faculty research interests in vertebrate biology since the University's founding.
Studies of the genetic structure of natural populations of animals and plants focus on understanding patterns of dispersal, and the nature of barriers to gene exchange together with studies of ecology and behavior, such studies allow detailed analysis of how genotype, phenotype, and environment combine to determine evolutionary trajectories.
There is a huge array of sub-disciplines or branches of biology all up more than 60. Many have been around for hundreds of years, whilst others are far newer and are often developing very rapidly.
Fields of study such as evolution, ecology, and genetics are themselves very broad topics and contain many specializations within each field. For example, an ecologist, who looks at how organisms interact with each other and the environment, might specialize in marine ecology, population ecology, plant ecology or freshwater ecology.
As biology is such a broad field of study, the work from one biologist to another may be completely different. An agriculturalist for example, who is interested in the production of crops, will focus on very different content to that of an ethologist, who studies the behavior of animals. In order to be a well-rounded biologist, however, it is good to have an understanding of the basics of the broad fields within biology.
Last edited: 21 August 2018
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