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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:

Transport Videos Page Topics Brownian movement, Osmosis, Elodea Osmosis, Elodea Hypertonic, Elodea Hypotonic, Blood Isotonic, Blood Hypertonic, Blood Hypotonic, Osmosis in Red Onion, Paramecium Contractile Vacuole, Bulk Transport, Paramecium Endocytosis, Paramecium Exocytosis, Links to Transport Videos and Animations. Brownian Movement Brownian movement (motion) is the random movement of suspended particles in a gas or liquid that is caused by the molecular motion (collisions) of surrounding molecules (and particles) of the medium. In biological systems osmosis is defined as the diffusion of water (from an area of high concentration to an area of low concentration) across a selectively permeable membrane. Elodea - Osmosis Elodea is a common freshwater plant that is frequently used to decorate aquariums. Elodea - Hypertonic Solution A hypertonic solution is a solution that contains more (hyper) solutes than the cytoplasm of the cell. Elodea - Hypertonic Cells in a Hypotonic Solution Blood - Isotonic Solution

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

A Closer Look at Evolutionary Faces To recreate the faces of our early ancestors, some of whom have been extinct for millions of years, sculptor John Gurche dissected the heads of modern humans and apes, mapping patterns of soft tissue and bone. He used this information to fill out the features of the fossils. Each sculpture starts with the cast of a fossilized skull; Gurche then adds layers of clay muscle, fat and skin. Gurche, a “paleo-artist,” even molds the hominids’ eyes out of acrylic plastic, eschewing pre-fabricated versions. The sculpture above is of Lucy’s species, Australopithecus afarensis, which walked the earth roughly three million years ago.

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.

Photosynthesis and Respiration 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.’

Creative and Healthy Snack Ideas Creative and healthy snack ideas kids love! It is a good way to incorporate more fruits and vegetables too! Remember kids need 3-5 servings of fruits and vegetables a day for their optimal development! 1.- Pepper Monsters. 2.- Fruit Kabobs and Yogurt Dip. made of stainless steal and great to serve kids veggies in a creative and super fun way! Please see my other post for more fruit pop ideas: fruit pop ideas 3.- Go Fishing. and goldfish crackers. You can make your own goldfish with a simple recipe with only 4 ingredients. , they have several sizes for you to choose from. What a fun idea! 4. 5. or the MSC 3pc Flower Power Cutter Set to make wonderful fruit art! Recommended Products: Related 5 Back To School Healthy Lunchbox Ideas Yes, it is time to go back to school again and we need at least 5 Back To School Healthy Lunchbox Ideas! August 20, 2015 In "Favorite Products" 10 Disney Frozen Fun Food Party Ideas May 19, 2014 In "Fun Food Ideas" Fun Fruit Pop Ideas May 10, 2015 In "Finger Foods"