Natural Selection vs. Divine Creation
Essay - 3 pages - Biology
From the beginning of the ideas presented by Charles Darwin in The Origin of Species, and their gaining support from the scientific community, the theory of evolution was been met with opposition. A great deal of this opposition came from religious groups who believed in a creation from a divine...
Information System's Theory
Essay - 2 pages - Computer science
Karl E. Weick is one of the most influential people when it comes to organizational strategy and information systems. He was born on October 31, 1936 in Warsaw, Ind. and has served as a theorist and information specialist for many years, most recently at the University of Michigan (where he...
Effects of Road Salt on Germination and Growth
Tutorials/exercises - 11 pages - Biology
This report examined the effects of road salt in relation to growth and germination in the Brassica rapa, a common turnup flower. The initial questions considered if the salt would actually affect the growth. There were four groups of plants which were collected. The groups included a control...
Results and Figures of Salt on Germination and Growth
Essay - 3 pages - Biology
Finding the effects of salt on germination and growth of plants took twenty-two days of research. Each collection day the height, height of the leaf, color, height of the node, number of buds, and the number of the flowers were taken into account. Based on the original hypothesis stating that the...
Brassica Rapa in Comparison With Sodium Chloride
Essay - 4 pages - Biology
In this study the Brassica Rapa will be tested to see if salt water effects it's growth. Data will be taken from four different types of groups: distilled water; 0.25% of sodium chloride; 1.00% of sodium chloride; and 4.00% of sodium chloride. Data will be collected in a twenty-two day span,...
How Mad is Reefer?
Essay - 4 pages - Physics
From the age of twelve and older nearly 40% of our country, about 98 million Americans, has used Cannabis sativa for its psychological and physiological effects in much the same way as it has been throughout recorded history (AMA Council). This lengthy past has constructed a harsh stigma around...
Taking Candy from Strangers: Why Not?
Essay - 3 pages - Computer science
The word “stranger” carries negative connotations in society, especially when associated with the Internet. Parents are lectured by authorities to monitor their children's use of chat rooms. E-mail filters remove millions of unwanted and sometimes grotesque advertisements from strangers...
The Social History of LSD
Essay - 4 pages - Biology
When Albert Hofmann created LSD 25 during experimentation in his laboratory, he had no idea what was to become of it, or what kind of an impact it would have. "Dr. Humphry Osmond invented the term 'psychodelic', which was later amended to 'psychedelic to get rid of the nuthouse...
The CCR5-Delta 32 Genetic Mutation and Human Evolution - published: 27/11/2007
Essay - 2 pages - Biology
Genetic mutations are not uncommon. They can happen for a variety of reasons and have a variety of effects. Those with negative effects are weeded out by natural selection, and those with positive effects prevail and are accumulated due to natural selection. These mutations can be caused by a...
Venomous Lizards
Essay - 2 pages - Biology
The two venomous lizards of the world are impressive creatures about which much misinformation has been spread for centuries. They have been thought to possess supernatural features such as poisonous breath, a stinging tail and the ability to spit their venom. The Gila monster (Heloderma...
Venomous Snakes
Tutorials/exercises - 4 pages - Biology
The term pit viper comes from the presence of paired, highly sensitive, thermoreceptor organs (pits) present on the forward portion of these snakes' heads. These structures, also known as foveal organs, serve the snake in locating prey, aiming strikes, and adjusting venom dose. The foveal...
An Assessment of Historical and Contemporary Land Use at Hedgehog Mountain, Freeport, Maine, via Field Observation
Case study - 5 pages - Biology
The purpose of this investigation was to collect information that allowed the formulation of a hypothesis as to the land-use history of the Hedgehog Mountain preserve, and to correlate empirical observations with a limited literature review in an attempt to validate the hypothesis presented. The...
Genes and Chromosomes
Tutorials/exercises - 6 pages - Medical studies
As a first approximation, genes can be defined as stretches of DNA that encode a single protein or a single functional RNA, such as an rRNA or tRNA. There are exceptions to this rule because there are mechanisms, such as alternative splicing of the primary RNA transcript into different mRNAs,...
Pelvic Circulation
Tutorials/exercises - 2 pages - Medical studies
At the bifurcation of the aorta, the middle sacral artery arises posteriorly and travels on the pelvic surface of the sacrum to supply branches to the sacral foramina and the rectum. The common iliac arteries arise at the level of the fourth lumbar vertebra, run anterior and lateral to their...
Pelvic Innervations
Essay - 2 pages - Medical studies
Surgical Anatomy of the Retroperitoneum, Kidneys, and Ureters; only the pelvic courses of its nerves are reviewed here. The iliohypogastric nerve (L1) travels between, and supplies, the internal oblique and the transversus muscles and pierces the internal and external oblique muscles 3 cm above...
Anatomy of the Lower Urinary Tract and Male Genitalia
Tutorials/exercises - 4 pages - Medical studies
The pelvic bones are the sacrum (the termination of the axial skeleton) and the two innominate bones. The latter are formed by the fusion of the iliac, ischial, and pubic ossification centers at the acetabulum. The ischium and pubis also meet below, in the center of the inferior ramus, to form...
The Amnion
Tutorials/exercises - 3 pages - Medical studies
The amnion at term is a tough and tenacious but pliable membrane. It is the innermost fetal membrane and is contiguous with the aminonic fluid. This particular avascular structure occupies a role of incredible importance in human pregnancy. In many obstetrical populations, preterm premature...
Blood Circulation in the Mature Placenta
Tutorials/exercises - 2 pages - Medical studies
Because the placenta functionally represents a rather intimate association of the fetal capillary bed to maternal blood, its gross anatomy primarily concerns vascular relations. The fetal surface of the placenta is covered by the transparent amnion beneath which the fetal chorionic vessels...
Organization of Placenta
Tutorials/exercises - 2 pages - Medical studies
From the electron microscopic studies of Wislocki and Dempsey (1955), data were provided that permitted a functional interpretation of the fine structure of the placenta. There are prominent microvilli on the syncytial surface, corresponding to the "brush border" described by light microscopy....
Embryonic and Placental Development
Tutorials/exercises - 2 pages - Medical studies
In a description of the earliest stages of the human blastocyst, the wall of the primitive blastodermic vesicle was characterized as consisting of a single layer of ectoderm. As early as 72 hours after ovum fertilization, the 58-cell blastula had differentiated into 5 embryo-producing cells and...
Immunological Acceptance of the Conceptus
Tutorials/exercises - 3 pages - Medical studies
Over the last half century, many attempts to explain the survival of the semiallogenic fetal graft have been proposed. One of the earliest explanations was based on the theory of antigenic immaturity of the embryo-fetus. This was disproved by Billingham (1964) who showed that transplantation...
Fetal Tissues of the Fetal-Maternal Communication System
Tutorials/exercises - 5 pages - Medical studies
The extravillous and villous trophoblasts are the embryonic-fetal tissues of the anatomical interface of the placental arm; the avascular fetal membranes—the amnion and chorion laeve—are the fetal tissues of the anatomical interface of the paracrine arm of this system. The placental...
The Decidua
Tutorials/exercises - 4 pages - Medical studies
This tissue is the specialized, highly modified endometrium of pregnancy. The transformation of secretory endometrium to decidua is dependent upon the action of estrogen and progesterone and other stimuli provided by the implanting blastocyst (or maternal platelets) during trophoblast invasion of...
Prementrual Syndromes
Tutorials/exercises - 2 pages - Medical studies
A variety of maladies, sometimes disabling, beset many ovulatory women in a recurrent manner during the luteal phase of each ovarian cycle. Although the biological basis for this association is not defined, evidence points to a causal relationship between progesterone secretion and withdrawal and...
Clinical Aspects of Menstruation
Tutorials/exercises - 2 pages - Medical studies
Menstruation is the periodic discharge of blood, mucus, and cellular debris from the uterine mucosa. Menses occur at more or less regular, cyclical, and predictable intervals from menarche to menopause except during pregnancy, lactation, anovulation, or pharmacological intervention. It is...
Delirium
Tutorials/exercises - 3 pages - Medical studies
Delirium, a clinical syndrome characterized as an acute disorder of attention and cognitive function, is the most frequent complication of hospitalization for elders and a potentially devastating problem. Delirium often is unrecognized despite sensitive methods for its detection, and its...
Intraneuronal Signaling Pathways
Tutorials/exercises - 7 pages - Biology
Prior to delineating the organization of specific intraneuronal signaling pathways, it is important to consider, in general terms, their role in helping neurons interpret and respond to the barrage of afferent stimulation impinging on them continuously. From an evolutionary perspective, second...
Ion Channels
Tutorials/exercises - 6 pages - Biology
Structure and Function of Voltage-Gated Ion Channels Voltage-gated ion channels allow the flow of ions in response to changes in membrane voltage and are key elements in neuronal excitation and inhibition. Although ion channels can usually pass more than a single type of ion, voltage-gated...
Neurotransmitter and Ion Channels
Tutorials/exercises - 3 pages - Biology
Classes of Neurotransmitters Much of the information transfer between neurons in the CNS occurs via chemical synapses. These synapses use a variety of messengers (neurotransmitters) that are released in a Ca2+-dependent fashion from presynaptic terminals and act on specific protein receptors to...
Sybaptic Plasticity
Tutorials/exercises - 4 pages - Biology
In its simplest form, the postsynaptic response to neurotransmitter release can be mediated by a single protein complex. For example, nicotinic acetylcholine receptors are self-contained stimulus-response modules that both detect a stimulus, acetylcholine, and generate a response, passage of ion...
