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How Cells Divide

How Cells Divide
share By Rick Groleau Posted 10.09.01 NOVA Most of the time, when a cell in our bodies divides, each new cell carries a complete set of chromosomes. The cells involved with human reproduction, however, carry only half after division occurs. In this step-by-step explanation, learn about mitosis and meiosis, the two types of cell division. This feature originally appeared on the site for the NOVA program 18 Ways to Make a Baby. Background on Meiosis and Mitosis As viewed from a human perspective, nature seems to have done ingenious engineering to overcome obstacles. Asexual reproduction relies on a process called mitosis, in which the nucleus of a cell divides to create two new nuclei, each containing an identical copy of DNA. Meiosis, on the other hand, is the process by which certain sex cells are created. How exactly does meiosis halve and mix chromosomes?

Howard School: Employment Opportunities for professional and career development are outstanding at The Howard School.Lead teachers (including arts and physical education) should bring a strong background in teaching usingan integrated curriculum and personalized instruction. Candidates should be particularly interested in working in a highly collaborative environment. Preference is given to those with three to five years of experience and an advanced degree in education or a related field, as well as to those with expertise in particular disciplines. Most lead teachers are certified by the state of Georgia in their primary field of teaching responsibility. Support teachers work in the classrooms with lead teachers, expanding opportunities for more individualized instruction and collaborative teaching. Support teachers are required to have a bachelor’s degree and experience in working with children in a learning environment. To apply for these positions, please fax, mail, or email a cover letter and resume to:

Exercising restores sensitivity of neurons that make one feel full There is now another good reason to exercise. Besides burning calories, exercise restores the sensitivity of neurons involved in the control of satiety (feeling full), which in turn contributes to reduced food intake and consequently weight loss. This is the conclusion of a study led by Brazilian researchers at the University of Campinas, and the findings will be published next week in the online, open access journal PLoS Biology. This disclosure may bring hope to over 40% of the population that suffers from weight problems and obesity around the world. The increase in obesity has become one of the most important clinical-epidemiological phenomena. The group led by José Barreto C. Physical activity has always been considered a cornerstone in the treatment of obesity, however, only now have the effects of exercise on the control of body weight been understood.

Lemon Berry Napoleon Remember these Grilled Chicken and Avocado Napoleons, and these Raspberry Lemon Bars? Well, every Monday night we have family night. We play games, have a little lesson, sometimes a family council meeting to talk about the upcoming week, etc. It’s a great way to stay connected as a family. Do the Men in Your Life Prefer Chocolate or Fruit Desserts? I adore lemon curd. I think the cooking class instructor that told me that is wrong. These napoleons are the perfect summertime dessert with the perfect flavor combo-raspberries and lemon. Buttery, flaky puff pastry filled with creamy lemon curd, fresh whipped cream and juicy raspberries. Ingredients 1 Package Pepperidge Farm Puff Pastry, rolled out and cut into 6 rectangles 1 Pint Fresh Raspberries Whipped Cream 1 1/2 Cup Heavy Cream 2/3 Cup Powdered Sugar, plus extra for garnish Lemon Curd Cream 1 Cup Lemon Curd1/3 Cup Fresh Whipped Cream Instructions Heat the oven to 400 degrees. For the Heavy Cream To Assemble Notes Lemon Curd Berry Pie

Misfolded neural proteins linked to autism disorders An international team of scientists, led by researchers at the University of California, San Diego, has identified misfolding and other molecular anomalies in a key brain protein associated with autism spectrum disorders. Palmer Taylor, associate vice chancellor for Health Sciences at UC San Diego and dean of the Skaggs School of Pharmacy and Pharmaceutical Sciences, and colleagues report in the Sept. 10 issue of the Journal of Biological Chemistry that misfolding of a protein called neuroligin-3, due to gene mutations, results in trafficking deficiencies that may lead to abnormal communications between neurons. Genetic misfolding of neuroligins is thought to prevent normal formation and function of neuronal synapses. The gene mutation has been documented in patients with autism. "It makes sense that there's a connection," said Taylor. Neuroligins are post-synaptic proteins that help glue together neurons at synapses by connecting with pre-synaptic protein partners called neurexins.

Scholarships for Teachers | Certification Map Being a teacher is tough enough, without the financial worry related to ongoing educational expenses. Those seeking either undergraduate or graduate educational degrees — such as a Master of Education or a Master of Arts in Teaching — may find it difficult to obtain the needed funds to do it. Fortunately, many organizations recognize this challenge by offering scholarships for teachers. We’ve also added state specific scholarships for teachers to each of our state pages. ACS – Hach Second Career Teacher Scholarship Organization: American Chemical Society (ACS) Availability: Scholarship applicants must hold a Bachelor’s degree (or higher) in Chemistry or related discipline, along with work experience in a chemistry-related profession. AFCEA STEM Scholarship Organization: AFCEA / The National Science Teacher Association Availability: Students must be U.S. citizens with a minimum overall GPA of 3.0 (or equivalent). AKAEAF Graduate Scholarships Agnes Jones Jackson Scholarship Hubertus W.V.

Google Reader (10) 4 Do’s & Don’ts for getting better sleep | Bneato Bar It’s a commonly known fact that adults between 19-55 years old need about 8 hours of sleep every night. It’s less known that sleep deprivation causes 20% of all car accidents, increases chance of depression ten-fold, and is even correlated to weight gain (source). But regardless of all the facts and figures, we know deep down that a good night’s sleep is just plain good. There are a lot of ways to improve your sleep between managing your schedule, changing your sleep position or adjusting to disturbances from your partner – but here are a few quick Do’s and Don’ts regarding the space around your bed and how you can improve your sleep and start your day off a little bit better. DON’T: Keep anything near your bed that gives off light. According to the National Sleep Foundation, ‘exposure to light stimulates a nerve pathway from the eye to parts of the brain that control hormones, body temperature and other functions that play a role in making us feel sleepy or wide-awake.’

Climate change remains a real threat to corals Hopes that coral reefs might be able to survive, and recover from, bleaching caused by climate change may have grown dimmer for certain coral species, according to new research by University at Buffalo marine biologists published this week in PLoS One. The research shows, for the first time, that while hard corals can take up from the environment new stress-tolerant algae that provide critical nutrients, the coral may not be able to sustain the relationship with these algae over a long period, a process known as symbiosis. The findings may mean that certain types of coral will not be able to adapt rapidly enough to survive global warming, says the study's lead author, Mary Alice Coffroth, PhD, UB professor of geological sciences in the College of Arts and Sciences. The demise of coral reefs deprives fish of food and shelter, which reduces reef fish populations and marine diversity. Co-authors on the paper include Eleni L.