Biology Essays

A transgene is a gene with desirable characteristics that is moved from a source organism implanted into a new organism in order to improve the desired characteristics of the recipient organism. This is an improvement from the traditional process of breeding wherein a plant or animal with a desired trait is mated with an existing plant or animal.

There is many types of learning, the most basic form of which is non-associative learning. Surprisingly noticed even in primitive life forms, such as the protozoan Stentor coeruleus, it represents a type of learning where the organism becomes aware that some events are unrelated and irrelevant.

The author discusses ethical and moral arguments of using embryonic stem cells. Arguments of groups or sectors opposing the use of embryonic stem cells revolve around the destruction of life because they consider the cell in the embryo as not just a simple cell but life itself or the beginning of a human being.

The combination of embryological and genetic zebrafish leads to the external development of the transparent embryo, which allows fundamental vertebrate development process from gastrulation to organogenesis to be visualized and studied. Also, the heart beats and the blood circulation of the embryo are readily observed.

There are three major sources of such variations, namely, the independent assortment of chromosomes during meiosis,reciprocal recombination of the linked genes on chromosomes by crossing over in prophase I of meiosis,and random fertilization of gametes, thereby raising possibility of innumerable combinations.

The author states that the males of the species bear plate-like membranes on the thorax; vibrations of these plates enable them to produce loud, shrill sound, while the females of the species are silent. This is their mating sound. The life cycle of the insect passes through different phases once the mating of the pairs is done.

In simple words, the parent cell gets separated into two daughter cells that are similar to the parent cell in the process of mitosis. However, the process of meiosis can be described as the cell division that occurs through sexual reproduction of eukaryotic cells.

The notion that biology has anything to do with destiny has existed since the formation of biology. This notion begets the question: when and where did biology begin? Did it begin with creation? Did it evolve? How is it linked with the present day and where is it headed? The answers are as complex as the questions. But they are interesting looking into.

The influenza virus genome has a segmented structure. This facilitates in the exchange of gene segments between two different strains of viruses which coincidentally happen to be infecting the same cell. Such an exchange can occur if dual infection occurs in a host with both the human and avian strains of the influenza virus.

Generally speaking, water is the most abundant component of living organisms. For most animal and plant cells, water accounts for the 70-90% of their compositions. The lowest cases are that of seeds which are 20% water while the most extreme is the jellyfish which is 99% water.

Because stress hormones activate catabolic processes the risk of obesity during chronic stress is increased significantly. There was proved that chronic activation of the hypothalamic-pituitary-adrenal axis could result in an increase of the adiposity, decrease muscle component of lean body weight and insulin resistance. 

Eukaryotic proliferation and succession requires mechanisms which efficiently build up the multicellular structure and care capable of maintaining and replicating it. These mechanisms are presented in the form of mitosis and meiosis. The wear and tear of the body results in the sloughing of millions of cells everyday.

Hepatitis is yet another group of viral infections spread through bodily fluid exchange. Some forms of hepatitis can be spread through fecal contamination as well as sexual contact, but for the purpose of this paper, we will only look at hepatitis spread through sexual contact. Patients suffering from hepatitis infections often suffer liver damage. 

The author states that in the USA, IDDM is responsible for only 5 percent or less for causing diabetes. IDDM causes more impact on life compared to non-insulin-dependent diabetes (NIDDM). IDDM is caused by a reaction caused in the body such that the immune system loses the capability of insulin-secreting cells in the pancreas.

The following articles analyze and demonstrate current research on the topic of ‘photosynthesis’. Each is concerned with scientific research and measurable analysis of the photosynthetic processes.  The test methods of certain scientific questions and studies offer unique theoretical insights and interpretations of scientific methodologies.

They have unique values, precedence and behavior. They take part in by dissimilar rules. Scientists have come to believe that a few basic differences between them are genetic. It turns out that men's and women's brainpower, for instance, are not only unmatched, but the way they make use of them fluctuates too.

Ten-month-old puppies will be subjected to simple intellectual tests to evaluate their early abilities to learn. Abilities to learn through identifying sounds and visual materials will be assessed for all the set-ups. The puppies will then be evaluated for learning abilities for simple commands such as sitting, standing and walking.

Cancer cells developed resistance to chemotherapeutic agent by various means like mutation and over expression of Drug target, enzymatic inactivation of drug. Efflux mediated elimination of drug from cells etc. this phenomenon is mainly observed in case of recurring tumors after initial chemotherap.

This research will begin with the statement that when it comes to the human body, energy is necessary for the body to function in the slightest. Without energy, the body cannot function. Furthermore, in order to remain healthy, the body needs a level of nutritional balance. The paper tells that the body needs to have a proper level of nutrients in order to function properly.

Every chemical element has got species of atoms which may be one or more than one with same atomic number i.e. having the same number of protons in the nucleus; the same position in the periodic table; similar chemical properties but different atomic masses and physical characteristics.

These help them to attract the female and spread the threat to others. In adult leopard limits in size is vary from 2inches to 5 inches in length, where as female usually bigger then male. They usually do active at night time.

The author states that the stacking of cisternae membranes is thought to reflect the mechanism which must be present for the production of enzymes and proteins. Other examinations conducted by scientists have also shown that GRASPs play an important role in the development of the Golgi Apparatus during the mitotic division.

The apomorphic aranaemorphs have a specialized web, in which piriform silk is added to stabilize the line. In addition, these spiders have female fertilization ducts. All of these characteristivs are synapomorphies,that make Aranaeomorphae monophyletic (Coddington, 2005).

The author states that there are several stages of Meiosis. The first one is prophase where homologous chromosomes start pairing and form synapses. The second stage is Metaphase where these pairs are situated on the Metaphase plate. There are equal chances of receiving the mother’s or father’s homolog for each chromosome.

He of course is not talking about the rights that shouldn't be discussed, and immediately dismisses those. But the rights that do matter, those are the one that he feels should not just be given to us, but all animals. If presented with the topic of animal experimentation, even if it was harmless, I believe that Singer would bounce the question back at the asker and ask if they would feel comfortable running the test on a human.

Medical researchers first study the disease or a health problem thoroughly before they develop different ways of treating it. There are some diseases and health problems which entail method that can be studied only in a living being. In the medical and psychological field, animals are frequently used for researches.

The author states that the immune system reacts to the situation and tries to destroy the pathogens containing these antigens. The antigens are generally in the form of proteins. Once the immune system comes across such substances, it also creates immunological memories, which help in preparing it for future attacks of this nature.

In the Proterozoic Era, 2.5 billion to 544 million years ago, the atmospheric level of oxygen increased to 15% due to oxygen producing cyanobacteria.  The levels of oxygen in the atmosphere produced a fatal environment in which anaerobic organisms needed to evolve methods of coping with the presence of oxygen.

The author states that the larynx is suspended from the hyoid bone; the only bone in the body that is not attached to any other bone. The larynx’s structure is comprised of the thyroid cartilage, cricoid cartilage, epiglottis, arytenoid, cuneiform, and corniculate cartilages. At the anterior part of the larynx is the thyroid cartilage.

According to the essay eugenic policies include compulsion through state legislation or persuasion through counseling, particularly for citizens with genetic defects. Laws are passed that limit the number of children a family can have, although in countries like China, it has something to do with controlling its population explosion.

This paper will begin with the statement that the mitochondria (singular form is mitochondrion) are the principal energy source of the cell. Aside from doing other specialized tasks, mitochondria convert nutrients into energy. They are normal structures responsible for energy production in cells. They are located in the cytoplasm outside the nucleus of the cell.

The author states that other members of the family were recently found to be expressed in normal cells, indicating that the family is larger and more disparate than initially expected. MAGE-like genes have also been identified in non-mammalian species, like the zebrafish or Drosophila melanogaster.

A key factor to this argument is that primates relied on sight over smell. They were able to develop a keen sense of depth perception, perhaps because of the constant leaping that was necessary to move about the trees.

In order to grow the plants, young spikelets were collected from immature tassels at 2–3 d intervals from the mid-portion of tassels from plants segregating 1:1 for male-sterile:male-fertile plants. After the growth of the plants, the necessary anthers were selected and fixed, and processed for microscopy.

Goodall mentioned several examples by which chimpanzees and humans were similar, one superior to the other, or where each was in a league of its own and, therefore, incomparable.Based on the observations recounted in her book, chimpanzees and humans were similar because, among other characteristics, they used and modified tools, hunted, and ate meat. 

Abbreviations: Inr= initiator sequence of the RNA polymerase II promoter; UCE= upstream control element of the RNA polymerase I promoter. A 29 kilo base (kb) linear DNA fragment is digested with ApeK I, Bst I and Cla I, individually and in combination, and the resulting DNA fragment sizes are determined by agarose gel electrophoresis.

The author states that after people started gathering information regarding causes’ of depression starting with Brain functioning, hormonal role, environmental influence, and finally genetic basis of depression. The genetic composition of an individual plays a very important role in the predisposition of depression.

The author states that the evolution of populations can take place in the form of macroevolution and microevolution. In the former, very large changes occur over long periods of time. On the contrary, in the latter, small changes in a population occur within the same area, resulting in interbreeding.

Much progress has been made toward understanding the molecular basis of infectious diseases. Koch's postulates, the standard test for determining if a bacterium causes disease, have limitations. A new set of postulates, the molecular Koch's postulates, has been proposed and focuses on the role of genes and gene products in disease.

Breast cancer is one of the known cancer diseases whose cure remains speculative. Though doctors and researchers have always been blamed for not doing much to ascertain the real treatment of breast cancer, the lack of basic information about the disease has increased its spread. It is well understood that not everybody is a scientist. 

It has been suggested that genes are important too, but not sufficient for, not only development but also the explanation of development. It is a fact that the key to the sex determination of the fetus lies in the male spermatogenesis and the genetic constitution of the sperms. Out of 23 pairs of somatic chromosomes in humans, 22 pairs are somatic and 1 pair is sex chromosomes.

Neurofibromatosis is an autosomal dominant neurogenetic disorder. It can present with spectrum of symptomatology, it affects bone, nervous system, soft tissue and the skin.There are two varieties of neurofibromatosis, NF-1, popularly known as peripheral neurofibromatosis and NF-2, also known as central neurofibromatosis

D antigen is present on the red blood cells, the blood is known as Rh positive, and absence of D antigen confers Rh negativity. The D antigen is a potent alloantigen, meaning this can result in production of antibodies quickly on exposure.

To consider sneaking behavior, the use of the theory of sexual selection encompassing sneaking behavior must be considered. Roche clarifies this as “Sexual selection is distinguished from natural selection by Charles Darwin” (2006). Further, sexual selection and evolutionary requirements are designated as variance in the number of mates.

Everybody living in the forest enjoyed a unique place in the food chain and nobody had any problem with this natural arrangement.One day an old donkey came into this forest. Actually, a peasant living in the neighboring village owned this donkey, who had abandoned the donkey in the forest as he had grown old and was no more of any use.

Every urine specimen is assigned a bar code, and the machine identifies the specimen by it. Then, 800 μL of uncentrifuged urine is aspirated by the machine automatically. This specimen has crystalline content like urates. This is diluted 4 times to dissolve this and other crystalline content. This uses a dilution buffer to do this.

There have been studies conducted on the sexual behaviors among insects and perhaps the most considered subjects for experiments are the Drosophila species. Drosophila or fruit flies are two-winged insects and are usually modeled when it comes to genetic studies. They exhibit ideal complicated behaviors as well as optical recording and electrical neuronal activity.

Vitamin B12 is normally absorbed in the walls of the ileum. The vitamin helps in maturation of red blood cells. According to Doctor Mellissa Conrad (Conrad, 1996), the large multinucleated cells known as megaloblasts circulate in the blood cells but do not act like blood cells.

The success of the sharks can be attributed to the diversity of their evolution, having a simple yet flexible skeleton, as well as being hardy creatures, even withstanding the wide-ranged extinctions of numerous species during the Permian-Triassic transition (Compagno, 1990). Sharks are mostly found in tropical to warm-temperate waters and can live in depths as deep as 2000 meters.

“Often in nature things are not what they seem. A rock on the seafloor may be a poisonous fish; a beautiful flower in a garden may be a carnivorous insect lying in wait for prey. This misleading appearance extends to certain components of cells, including chromosomes-the strings of linear DNA that contain the genes.