According to researchers at the Center for Genomic Regulation, disruption of the circadian rhythm (the bodys natural biological clock) increases skin cells susceptibility to forming tumors and aging quicker due to the lack of cell regenera
Rob Ranson 4 November 2011 Circadian Rhythm and the Skin A recent study has revealed the importance of the body's circadian rhythm in the aging process and the regenerative capacity of skin stem cells. According to researchers at the Center for Genomic Regulation, disruption of the circadian rhythm (the body's natural biological clock) increases skin cells' susceptibility to forming tumors and aging quicker due to the lack of cell regeneration. The study, which was popularized by ScienceDaily, shines light on the importance of having a balanced sleep schedule -- something that, as a stressed college student, I seldom have the privilege to maintain. It also raises the question of just how important having a balanced circadian rhythm is, and how adverse the absence of one can be. Because stem cells regulate cell replacement in tissues, they constantly reproduce cells to replenish those that have deteriorated through daily use. Correctly functioning stem cells are essential for supporting healthy tissue, including dermal tissue, during the life of an organism. Every day, skin cells are exposed to various harmful agents such as ultraviolet rays and pathogens. The function of the skin is to protect from such dangers, while being an impermeable barrier that separates the inside of the body from the outside world. The study showed that when a circadian rhythm is interrupted,
The extinction of dinosaurs must have been related to a major event. Something enormous had to have happened in order to completely devastate these really massive animals.
Dinosaurs' Extinction: An Incredible Mystery by Shahznane Molou Introduction to Geoscience Dr. Peter Bolton 26 March 2009 Index Content......................................................................................................................................3 Bibliography...............................................................................................................................8 What were the dinosaurs? The first dinosaurs appeared 230 million years ago during the Mesozoic era which is also called "The Age of the Dinosaurs". They survived ice age until a big natural phenomenon hit the earth and extinct them (Buckley, 1997). There were basically two types of dinosaurs living in the earth. They were the Saurischia which were the dinosaurs of similar hips to reptiles of today; and the Ornithischia which were of bird hips. Scientists distinguished the reptilian hips due to the steepness of the hips themselves compared to the other bird-hipped dinosaurs (Power point on Dinosaurs from Dr. Bolton). A huge argument scientists have been through is whether dinosaurs were warm-blooded or cold blooded. The evidences that prove the first argument are the bone structures dinosaurs had which are very similar to us human beings. Their long legs show that dinosaurs were fast runners so there are chances they were warm blooded. However, other scientists
Components of Biological Membranes.
Components of Biological Membranes Introduction. Biological membranes surround all living cells, and may also be found surrounding many of an eukaryotes organelles. The membrane is essential to the survival of a cell due to its diverse range of functions. There are general functions common to all membranes such as control of permeability, and then there are specialised functions that depend upon the cell type, such as conveyance of an action potential in neurones. However, despite the diversity of function, the structure of membranes is remarkably similar. All membranes are composed of lipid, protein and carbohydrate, but it is the ratio of these components that varies. For example the protein component may be as high as 80% in Erythrocytes, and as low as 18% in myelinated neurones. Alternately, the lipid component may be as high as 80% in myelinated neurones, and as low as 15% in skeletal muscle fibres. The initial model for membrane structure was proposed by Danielli and Davson in the late 1930s. They suggested that the plasma membrane consisted of a lipid bilayer coated on both sides by protein. In 1960, Michael Robertson proposed the Unit Membrane Hypothesis which suggests that all biological membranes -regardless of location- have a similar basic structure. This has been confirmed by research techniques. In the 1970s, Singer and Nicholson announced a modified version
A comparison of marine organisms on shale & limestone coasts. Doolin, Ireland.
A COMPARISON OF MARINE ORGANISMS ON SHALE & LIMESTONE COASTS. DOOLIN, IRELAND. Introduction Doolin is situated in the Burren area of county Clare, Ireland. The area is famous for its limestone landscape and is highly acknowledged as an area of global importance for its flora, fauna and ecology. Doolin represents a unique limestone pavement and terrain which supports a diversity of rare marine habitats. In 1988, in recognition of its importance, the state Wildlife Service recommended the designation of the area as a Nature Reserve. Due to the extent of coastline in county Clare, the marine and coastal habitats are very important. The Atlantic Ocean off the west coast of Ireland is relatively clean compared to other oceans. This is illustrated by the amount of seaweed there. The Gulf Stream off the west coast of Ireland creates a warm, oceanic climate, which has a very significant influence on the species and habitats which occur in Doolin and increases the biodiversity. -Fig 01- Doolin Village The Doolin coast consists of both limestone and shale wave-cut platforms, both of which appear rich in diversity of flora and fauna. Doolin coast contains a wide range of invertebrates, some highly mobile, others fixed or sedatory, and shore fishes, are a characteristic feature. Brightly coloured lichens form distinct bands on the high shore, seaweeds are present in abundance,
Discuss how changes in control of the cell cycle contribute to cancer development Cancer is a multifarious disease, with a common feature that most tumours harbour one or more genetic mutations that allow them to advance outside their normal growth restr
Discuss how changes in control of the cell cycle contribute to cancer development Cancer is a multifarious disease, with a common feature that most tumours harbour one or more genetic mutations that allow them to advance outside their normal growth restraints. This proliferation is normally harnessed by the control of the cell division cycle, which in turn, is majorly regulated by the cyclin dependent kinases (Cdks) family of serine/threonine kinases and their regulatory partners, the cyclins (Errico, et al., 2009). In this essay, the roles of Cdks, cyclin complexes, regulatory proteins and other cell-cycle regulatory processes will be underlined, followed by an analysis of the genetic lesions in these regulators which may contribute to tumorigenesis. Fundamentally, cancer, or a neoplasm is a disease where cellular proliferation is no longer under normal growth control. The growth of this clone of cells exceeds, and is uncoordinated with that of normal surrounding tissues (NHS, 2009). Ultimately, this deregulation of growth and division of the cancer cells disrupts and interferes with the normal functioning of the body, either at its origin or through spreading to another location, eventually resulting in the potential death of the sufferer if left untreated. Other complex characteristics include the ability of the cancer cells to induce vascularisation of the tumour in
What are the roles of N- and O-glycans? Use examples to illustrate your answer.
Glycobiology tutorial II: oligosaccharide function Essay 2: What are the roles of N- and O-glycans? Use examples to illustrate your answer. Although the same glycosylation machinery is available to all proteins which enter the secretory pathway in a given cell, most glycoproteins emerge with characteristic glycosylation patterns and heterogeneous populations of glycans at each glycosylation site. What are the roles of these N- an O-linked glycans? Glycosylation and protein folding: The sugars play a role in protein folding and assembly. The proper folding and controlled assembly of many newly synthesized glycoproteins requires them to engage in a series of coordinated interactions with chaperones and enzymes through the attachment of a common oligosacchardide precursor, GlcNAc2Man9Glc3, to N-linked glycosylation sites. This sugar precursor is rapidly processed to GlcNAc2Man9Glc1 which can bind two lectins: the membrane bound calnexin (Clx) and its soluble homolog calreticulin (Clr). Lectins are oligosaccharide binding proteins. The interaction between Clx and/or Clr with nascent monoglycosylated glycoproteins provides access to a folding pathway. In their role as quality factors, Clx and Clr retain unfolded glycoproteins in the ER until they are correctly folded and assembled by chaperones, an event that is signalled by the permanent removal of the terminal glucose
Restoration Ecology
TABLE OF CONTENTS . INTRODUCTION ........................................................................... 2 2. WHAT IS RESTORATION ECOLOGY ................................................ 3 2.1 Overview .................................................................................... 3 2.2 Restoration ecology definition ............................................................. 4 2.3 Present state .................................................................................. 5 2.4 The need to create a conceptual framework .............................................7 3. RESTORATION ECOLOGY AND SUSTAINABLE DEVELOPMENT ........... 8 3.1 How can restoration ecology effectively contribute towards sustainable development? .................................................................. 8 3.2 Projections ................................................................................... 10 4. CASE STUDY: Converting a dairy farm back to a rainforest water catchment .......................... 12 5. RECOMMENDATIONS ................................................................... 15 6. CONCLUSIONS ............................................................................. 17 7. LIST OF REFERENCES ................................................................... 18 . INTRODUCTION The problem of ecosystem damage is global nowadays, and probably
What causes Anorexia
What causes Anorexia? For people with anorexia, it really is true that one can never be too thin. Despite being dangerously underweight, anorexics see a fat person when they look in the mirror. What they don't see is the tremendous physical and emotional damage that self-starvation inflicts, so they continue to diet, fast, purge, and over-exercise. While people with anorexia often deny having a problem, the truth is that anorexia is a serious and potentially deadly eating disorder. Fortunately, recovery is possible. With proper treatment and support, you or someone you care about can break anorexia's self-destructive pattern and regain your health and happiness. What exactly is anorexia nervosa? An example; (Maria's Story) Seventeen-year-old Maria has been on one diet or another since she was in junior high. She recently lost 10 pounds from an already slender frame after becoming a strict vegetarian. Her parents are concerned about the weight loss, but Maria insists that she's just under stress at school. Meanwhile, her vegetarian diet is becoming stricter by the day. Maria obsessively counts calories, measures food portions, and weighs herself at least twice a day. She refuses to eat at restaurants, in the school cafeteria, or anywhere else in public, and she lives on salad dressed with vinegar, rice cakes, and sugar-free Jell-O. Maria also has a large stash of
Discuss The Significance Of Normal And Abnormal Mitosis And Meiosis In The Lifecycle Of Humans
Discuss The Significance Of Normal And Abnormal Mitosis And Meiosis In The Lifecycle Of Humans. Introduction: Mitosis is a type of cell division. The nucleus divides once and produces two identical nuclei. The new daughter cells are genetically identical both to each other and the parent cells. The only source of genetic variation in the cells is via mutations. Mitosis is used for growth and repair. Some tissues must be repaired often for example, the lining of the gut, white blood cells, skin. The skin cell lifespan is only a few days. The same chromosome number is retained from generation to generation. The duplication of a chromosome is followed by a nuclear and cell division. Nuclear division its self is a continuous process, but for ease of description, four main stages are recognised. The four stages are known as Prophase, Metaphase, Anaphase and Telophase. When a cell is preparing to divide, it is said to be in Interphase. At this stage the cell forms new cell organelles to supply the daughter cells. The DNA replicates so the there is sufficient DNA for the two daughter cells. The cell then builds up its store of energy in preparation for the cell division. Mitosis starts with Prophase, where the chromosomes condense becoming more tightly coiled and folded and so appear more shorter and fatter as Prophase progresses. As soon as the chromosomes begin to condense,
Photo Identification methods
CONTENTS CONTENTS 1 USES OF PHOTO ID 2 TAKE PICTURES 2 WORKING CONDITIONS 2 UTIFITY 3 CRITERIA SELECTION PHOTO 5 SAMPLING 5 ERRORS 8 DISADVANTAGE 8 DATA COLLECTION 8 DATA ANALYSIS 8 OUR OBSERVATION - EXAMPLE PHOTO - ID 9 HUMPBACK WHALE 9 MINKE WHALE 11 WHITE - BEAKED DOLPHINS 12 DEDUCTION 14 REFERENCES 15 SUPPLEMENT 16 CHECKLIST USED PICTURE 16 OTHER INTERESTING PICTURE TAKE DURING USE PHOTO - ID 16 USES OF PHOTO ID Photo identification it use for watching and determining animals behavior, population biology and ecology. For example animals behavior can be group composition, social interactions and focal animals behavioral observations. For example population biology can be life span, birth rate, mortality rate and abundance estimates. Population must be definable because at least two and preferably more animals. Should be made to try to ensure that all animals have an equal probability of being captured during any one sampling. Should be made to try to ensure that all animals have an equal probability of being captured during any one sampling occasion. Better chance to capture the animals with a high probability of bias caprure number of recaptures up and leads to underestimation of population size. Identify an invidual animals is possibly, because we photographing sample of animals at deferent places - > enable movement and migration. It can also
