Someone’s hand moving to scroll through this blog post is possible because of a mineral that both gives bones their strength and allows muscles to move: calcium. As the most abundant mineral in our bodies, it’s essential for lots of important functions. It’s found in many foods, medicines, and dietary supplements.
Calcium keeps your bones strong, allows your muscles to move, and is important for many other bodily functions. The element is found in foods, medicines, and the world around us. Credit: Compound Interest CC BY-NC-ND 4.0. Click to enlarge.
You may know that antioxidants can help protect your cells from oxidative damage, but do you know about selenium—an element often found in special proteins called antioxidant enzymes? Selenium is essential to your body, which means you must get it from the food you eat. But it’s a trace element so you only need a small amount to benefit from its effects. In addition to its antioxidant properties, it’s also important for reproduction, DNA synthesis, and hormonemetabolism.
ATP (yellow) powering a protein (blue) that moves material within cells and helps them divide. Credit: Charles Sindelar, Yale University.
Just as electricity powers almost every modern gadget, the tiny moleculeadenosine triphosphate (ATP) is the major source of energy for organisms’ biochemical reactions. ATP stores energy in the chemical bonds that hold its three phosphate groups together—the triphosphate part of its name. In the human body, ATP powers processes such as cell signaling, muscle contraction, nerve firing, and DNA and RNA synthesis. Because our cells are constantly using and producing ATP, each of us turns over roughly our body weight in the molecule every day!
Our bodies can produce ATP in several ways, but the most common is cellular respiration—a multistep process in which glucose molecules from our diet and oxygen react to form water and carbon dioxide. The breakdown of a single molecule of glucose in this way releases energy, which the body captures and stores in around 32 ATP molecules. Along with oxygen, mitochondria are crucial for producing ATP through cellular respiration, which is why they’re sometimes called the powerhouses of cells.
Spheres of lipids (yellow) inside a cell. The nucleus is shown in blue. Credit: James Olzmann, University of California, Berkeley.
Have you ever wondered why your cells don’t spill into each other or what keeps your skin separate from your blood? The answer to both is lipids—a diverse group of organic compounds that don’t dissolve in water. They’re one of the four major building blocks of our bodies, along with proteins, carbohydrates, and nucleic acids. Types of lipids include:
Fats, necessary for our bodies’ long-term energy storage and insulation. Some essential vitamins are fat soluble, meaning they must be associated with fat molecules to be effectively absorbed.
When you encounter the word expression, you may think of a smile, a grimace, or another look on someone’s face. But when biologists talk about expression, they typically mean the process of gene expression—when the information in a gene directs protein synthesis. Proteins are essential for virtually every process in the human body.
RNA, though less well known than its cousin DNA, is equally integral to our bodies. RNA molecules are long, usually single-stranded chains of nucleotides. (DNA molecules are also made up of nucleotides but are typically double-stranded.) There are three major types of RNA, which are all involved in protein synthesis:
Messenger RNA (mRNA) is complementary to one of the DNA strands of a gene and carries genetic information for protein synthesis to the ribosome—the molecular complex in which proteins are made.
Transfer RNA (tRNA) works with mRNA to make sure the right amino acids are inserted into the forming protein.
Ribosomal RNA (rRNA), together with proteins, makes up ribosomes and functions to recognize the mRNA and tRNA that are presented to the ribosomal complex.
The intricate process of
mitosis—a cell splitting into two identical daughter cells—plays a pivotal role in sustaining life. Many scientists study this process to understand what’s needed for it to progress normally and why it sometimes goes awry, such as in cancer. During their research, the scientists often create eye-catching images and videos, and we showcase some of those visuals here.
Nerve cells, also known as neurons, carry information through our bodies using electrical impulses and chemical messengers called neurotransmitters. A nerve cell’s size and shape depend on its role and location, but nearly all nerve cells have three main parts:
Dendrites that extend like branches and receive signals
A cell body containing the nucleus that holds the genetic material of the cell and controls its actions
Dr. Melike Lakadamyali with a microscope. Credit: Courtesy of Dr. Lakadamyali.
“It would be a dream come true if I could look at a cell within a tissue and have a Google Maps view to zoom in until I saw individual molecules,” says Melike Lakadamyali, Ph.D., an associate professor of physiology at the University of Pennsylvania’s Perelman School of Medicine in Philadelphia. Her lab is helping make part of that dream a reality by developing super-resolution microscopy tools that visualize cells at a near-molecular level.
Blending Physics and Biology
Science and math fascinated Dr. Lakadamyali since childhood, and she felt especially drawn to physics because she enjoyed using logic to solve problems. After graduating high school in her native country of Cyprus, she chose to study physics at the University of Texas, Austin. She never gave much thought to applying physics methods to biological questions—a field known as biophysics—until her third year as an undergraduate, when she gained her first research experience in the lab of Josef Käs, Ph.D.
Dr. Lauren Parker Jackson. Credit: Vanderbilt University.
“A confusing experimental result almost always means you’ve stumbled upon something interesting and maybe even exciting. I think that’s what makes science fun,” says Lauren Parker Jackson, Ph.D., an assistant professor of biological sciences at Vanderbilt University, Nashville, Tennessee. Check out the highlights of our interview with Dr. Jackson to learn how she became a biologist and what she studies in her lab.
Q: What sparked your interest in science?
A: I credit my high school chemistry, physics, and biology teachers with getting me interested in science. They were quirky, they were talented, they were energetic, and they weren’t afraid to push us. As a teenager, I did a lot of science fairs and quiz bowls, where two teams compete to answer academic questions. As a high school junior, I took part in the Governor’s School for the Sciences and Engineering, where I spent a month at the University of Tennessee, Knoxville, studying chemistry in a lab. That exposed me to research for the first time.
Calcium keeps your bones strong, allows your muscles to move, and is important for many other bodily functions. The element is found in foods, medicines, and the world around us. Credit: Compound Interest CC BY-NC-ND 4.0. Click to enlarge.
