Category: stem

Biology 101: Gel Electrophoresis

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In this educational lesson, we learn about the purpose of gel electrophoresis and how gel electrophoresis works. Gel electrophoresis in a method of separating DNA. It can be used to separate the size of DNA, RNA, and protein. You first start with a variety of different fragments of DNA all mixed together. The gel is a porous matrix like a sponge and separates the DNA based on two main things: 1) size and 2) charge. The charge on DNA is what makes it move through the gel. DNA is a negatively charged molecule, so it will move towards a positive charge.

Chemistry 101: At Home Awesome Chemistry Experiments

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Chemical reactions happen around us all the time. These reactions occur when we cook or bake and even in our bodies, like when we breathe. Everyday objects are able to react and cause incredible reactions. Here are some easy science experiments you can create using things you can find around the house. Make sure you act safely during the experiment and have fun!

Calculus: Two Important Theorems – The Squeeze Theorem and Intermediate Value Theorem

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Learn about two very cool theorems in calculus using limits and graphing! The squeeze theorem is a useful tool for analyzing the limit of a function at a certain point, often when other methods (such as factoring or multiplying by the conjugate) do not work. This theorem also has other names like the Sandwich Theorem or the Pinch Theorem, but it is most commonly called the Squeeze Theorem. The Intermediate Value Theorem, often abbreviated as IVT, deals with a single function unlike the Squeeze Theorem.

Digoxin: How does Digoxin treat heart failure? Mechanism of Action and Side Effects [USMLE, Biology, MCAT, Medicine]

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Digoxin is a drug that treats heart arrhythmias, left ventricular systolic dysfunction, and heart failure. In this succinct educational lesson, we learn about how digoxin works in treating heart arrhythmias and heart failure, digoxin toxicity and common side effects, and treatment for digoxin toxicity. We also have a mini quiz at the end, so you can test your knowledge on the pharmacology of digoxin.

Working out …for your brain? – The Neuroscience and Benefits of Playing An Instrument

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Whether it’s a violin or a harmonica, learning to play an instrument takes time and effort to “perfect.” Musicians put hours and hours of hard work to perform in concerts, participate in competitions, or even just practice for fun at home. It can be frustrating to play the same piece hundreds and hundreds of times, especially if you still can’t get one section down. However, all of these hours of practicing actually do more than just putting on a perfect performance or impressing your family; playing an instrument can help your physical and mental state. 

Immunology: Treatments for Rheumatoid Arthritis – NSAIDs vs DMARDs vs Glucocorticoids [Biology, Medicine, MCAT, USMLE]

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Rheumatoid arthritis is an autoimmune disease characterized by chronic inflammation in the joints of hands, feet, knees, etc. In this quick and easy lesson, we explain the standard medical treatment for patients with rheumatoid arthritis at the USMLE immunology level, including DMARDS (synthetics and biologics), NSAIDS, and glucocorticoids.

Central Chemoreceptor vs Peripheral Chemoreceptor in Respiration [Biology, MCAT, USMLE]

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There are two types of chemoreceptors that help control and regulate our respiratory rate: 1) central chemoreceptors and 2) peripheral chemoreceptors. Both central chemoreceptors and peripheral chemoreceptors send signals to the main respiratory center in the brain that unconsciously tells our bodies to increase or reduce pulmonary ventilation. In this lesson, we describe the differences and similarities of central chemoreceptors and peripheral chemoreceptors for the pulmonary system.

Say… Cheese! A Look Into Fermentation – History and Making of Cheese

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From sour, sweet, and savory, cheese is a delicacy that connects people of all ages. It’s in hamburgers, pizza, salads, spaghetti, and desserts. Many of the world’s most popular dishes contain cheese, a food item that has been around humans for a long time. In this article, you will learn the incredible science that makes cheese possible.  Although the exact origins of cheese are unknown, it is thought that cheese originated when humans first began domesticating milk-producing animals like cows and goats. In fact, there is a legend that the first person to discover cheese was a merchant who found his milk curdled inside his container made of a sheep’s stomach. To his surprise, the curdled milk had a unique flavor that quenched his hunger. Cheesemaking is also shown in the artwork of a number of ancient civilizations including the Roman Empire and Ancient Egypt. However, the cheeses that are popular today were not made until cheesemaking became widespread across European countries around 500 years ago and then came to America when Pilgrims brought cheesemaking techniques with them. Since then, the cheese industry boomed in America and as of 2017, Americans consumed an average of 37 pounds of cheese every year per person! 

Biology Unit 5 Study Guide: Evolution

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Biology Unit 5 Study Guide: Evolution. After his visit to the Galapagos Islands, Darwin came up with the theory of evolution.  This theory stated that organisms change over time.  The way that organisms change is through the process of natural selection. With examples, practice questions, and answers to help make evolution respiration easy to learn!

Pushing Life’s Boundaries: Extremophiles Archaea

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Moderate and extreme are relative terms. What many assume to be the normal conditions for life do not apply equally across all species. Habitability can be thought of in terms of the Goldilocks principle. For example, to survive people need an environment that is not too cold and not too hot. Ranges like this exist for other factors as well, such as pressure. However, what is just right for us and most other creatures can be too much or too little for some. Animals that live on the sea floor provide an illustrative example in this regard. Where people need submersibles to maintain their equilibria, creatures that natural selection has adapted to thrive in the ocean’s depths are right at home. Cold, highly pressurized environments are the norm for them. When deep sea creatures are brought to the surface through accident or scientific curiosity they often either melt, as with glacial ice worms, or fatally decompress, like with blobfish. In this way the term extremophile is a relative one and is used to describe organisms that live in environments that are extreme to us. Beyond their novelty, extremophiles are important objects of study as they challenge and expand our notions of life and its necessities.

Biology Study Guide Book Just Published and on Sale! [Free Chapters]

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Hi Everyone! My friend just published a biology study guide book and it’s currently on sale! This book on biology study guides contains practice review questions and answers. Study Guides: Biology Unit Review Practice Questions and Answers . This interactive study guide of worksheets contains questions and answers to help you understand biology. Each unit contains information on key topics to review to further your understanding of biology. The units covered in this book include: ecology, biomolecules and cell biology, energy, photosynthesis, cellular respiration, cell division, mitosis, meiosis, protein synthesis, genetics, and evolution. Award-winning author and teacher Dr. Sam J. Alex created this study guide while inspired by students and teachers. All proceeds donated! Hope you find this book helpful on your journey into the wonderful world of biology and beyond!

Top 20 Best U.S. Colleges and Universities, Tips for Choosing the Right College, and the 8 Ivy League Colleges

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Application season! Every year, millions of students apply to colleges and universities with the hope of being accepted to their top choices. From coast to coast, the U.S. News ranks the top colleges and universities annually. Check out these top 20 best colleges and universities in the United States, tips for choosing the right college, and the 8 Ivy League Colleges.

What is Maladaptive Daydreaming Disorder?

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Daydreaming is a common human phenomenon, one that we all experience in our daily lives. Studies show that we actually spend around 47% of our waking time in the dream world. We utilize this important tool to think-out different scenarios, re-visit special times in our lives, imagine new ones, or even just to pass time. Daydreaming is vital to the human experience. But one may wonder, what happens when one daydreams a little too much?

Sleep 101: Brain Activity and Sleep Disorders, Sleep Apnea, Circadium Rhythms, and How to Sleep Better at Night

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Sleep and Brain Activity Sleep disorders affect up to 70 million people and cost around $15.9 billion annually. EEG stands for electroencephalography, which was used to examine human brain waves in the 1950s. Sleep Disorders: Insomnia, OSA, Apnea, Narcolepsy. Regulation of Sleep. Sleep-Wakefulness Cycle: Circadium Rhythm and Homeostatic System. Tips to sleep better at night.

Primary Essential Hypertension vs Secondary Hypertension: Causes and Health Effects of High Blood Pressure [Biology, MCAT, USMLE]

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In this quick, easy-to-understand lesson, we learn about secondary hypertension for USMLE and medicine. Secondary hypertension is defined as high blood pressure (>140/90 or >130/80) caused by an underlying disease, medical condition, or drugs. While primary essential hypertension comprises of the majority of hypertension cases (90%), only 10% of patient cases is secondary hypertension.

Direct Hernia vs Indirect Hernia

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Direct vs Indirect Hernia: What is the difference between direct and indirect inguinal hernias? In this easy-to-understand lesson, we explore the differences between direct inguinal hernias and indirect inguinal hernias. Overall, an inguinal hernia is a medical condition, where protrusion or bulge of abdominal contents into the groin area and/or inguinal canal. There are two types of inguinal hernias: 1) direct inguinal hernia and 2) indirect inguinal hernia.

Embryogenesis: Definition, Stages, and Development [MCAT]

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Sonic Hedgehog Gene. CNS development and Limb development. In embryology and developmental biology, embryogenesis is the development of an animal or plant embryo, starting with fertilization of an egg cell by a sperm cell. After fertilization, the ovum becomes a diploid zygote. orms forebrain, separates right and left brain, and establishes midline. f there’s a mutation, then we have a whole brain with no separation of right and left, which is bad. This is called holoprosencephaly. Left and right hemispheres fail to separate. There are also facial abnormalities, cleft lip/palate and even severe cyclopia (single eye like a cyclops).

The Rise of Tech: Tech Trends of the COVID-19 Pandemic

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The recent COVID-19 pandemic has turned our world upside down. From the way we greet each other to the schedule of our daily routines, it’s safe to say that everything that was considered the norm at the beginning of 2020 has completely changed. While most people’s eyes are on health officials, tech giants and start-up companies have been using this time to create new inventions to propel society further – or so they say. Here we will analyze the new products and tech trends that have arisen in the wake of this pandemic, what they do, and if they actually serve to help society.

Vaccines 101: Vaccination, Immune System, and the COVID-19 Vaccine – Benefits and Side Effects

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The question of how a vaccination would work to combat the current COVID-19 pandemic is a major concern right now. Everybody has their own perspective on the situation, and in some people’s minds, vaccines do not fit into the equation. Therefore, it’s extremely important to understand what a vaccine’s purpose is, how it is supposed to achieve that purpose, how a vaccine is developed, and its benefits versus side effects before coming to a final conclusion on the subject as it relates to the pandemic. To understand a vaccination’s purpose it is necessary to first understand how a pathogen works. A pathogen is essentially any foreign material (foreign in the sense that it is not a part of the human body), that can cause disease or a malfunction of the body. They spread from surface to surface and person to person.

Biology 101: Microfilaments vs Microtubules in Cell Biology

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Microfilaments and microtubules are both important elements of the cytoskeleton, maintaining the structure and integrity of the cell, but there are several differences between microfilaments and microtubules. In this article, we share this information on microfilaments versus microtubules.

Microfilament and Microtubulues are made from different individual subunits. Microfilaments are made from ACTIN, while microtubules are made from TUBULIN.

Cardiology 101 – Atrial Fibrillation (USMLE) : Causes, Symptoms, Diagnosis, and Treatments

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In this quick easy-to-understand lesson, we learn about atrial fibrillation, causes, symptoms, diagnoses, and treatments for USMLE medicine. Atrial fibrillation is the most common type of cardiac arrhythmia. This means the heart beat has an irregularly irregular rhythm. Symptoms can include fatigue, dyspnea (difficulty breathing), and heart palpitations in the chest. You diagnose atrial fibrillation via EKG. It can be treated with medications or surgically.

Immunology 101: Innate Immunity vs. Adaptive Immunity

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Innate vs Adaptive Immunity: What are the differences between innate and adaptive immunity? The human body has two protective immunological systems against pathogens: the innate immunity and the adaptive immunity. In this quick and easy lesson, we will explain the differences between the innate and adaptive immunity. The innate immunity and adaptive immunity differ based on the type of components that are used to protect the human body. For example, the innate immunity consists of neutrophils, dendritic cells, natural killer cells, macrophages, complements, physical barriers. On the other hand, the adaptive immunity contains components such as T cells, B cells, and antibodies to protect us from viruses, bacteria, and other pathogens.