Anne Helmenstine

About Anne Helmenstine

Anne Helmenstine is a science writer and scientist with multidisciplinary training. She holds bachelor of arts degrees in physics and mathematics from Hastings College (Hastings, Nebraska) and a doctorate of philosophy in biomedical sciences from the University of Tennessee (Knoxville, TN). Dr. Helmenstine is the owner of the Science Notes website, started in 2013. She has written articles for many websites on science topics. Dr. Helmenstine has been a college professor and scientist. She is also a musician and jewelry design artist. Interests include travel, water sports, and amateur astronomy. She is presently a full-time freelance science writer, illustrator, and photojournalist, working out of Myrtle Beach, South Carolina.

Dark Energy Definition — Get the dark energy definition and explanation. See how dark energy accounts for the accelerating expansion of the universe.

Dark Energy

This entry was posted on September 17, 2023 by Anne Helmenstine (updated on September 22, 2023)

Purines and Pyrimidines — Learn about purines and pyrimidines in biochemistry, including their structures, properties, functions, and sources.

Purines and Pyrimidines

This entry was posted on September 16, 2023 by Anne Helmenstine (updated on September 22, 2023)

Alkaline vs Acidic — Compare alkaline vs acidic in chemistry and everyday life with the definitions of the terms and examples. See how they relate to pH.

Alkaline vs Acidic

This entry was posted on September 13, 2023 by Anne Helmenstine (updated on September 22, 2023)

Mitosis vs Meiosis — Learn about mitosis vs meiosis. Compare and contrast the two forms of cell division, focusing on the difference between them.

Mitosis vs Meiosis Recently updated !

This entry was posted on September 12, 2023 by Anne Helmenstine (updated on September 25, 2023)

Commutative Property — Learn about the commutative property in math. Get the definition and examples of the property and compare it to the associative property.

Commutative Property in Math – Definition and Examples

This entry was posted on September 10, 2023 by Anne Helmenstine (updated on September 22, 2023)

Concave vs Convex — Learn the difference between concave vs convex for lenses, mirrors, polygons, and mathematical functions. See how to remember the difference.

Concave vs Convex

This entry was posted on September 9, 2023 by Anne Helmenstine (updated on September 16, 2023)

Are Two Atoms of the Same Element Identical — Learn whether two atoms of the same element are identical and see how they can vary. Discover how to identify an atom.

Are Two Atoms of the Same Element Identical?

This entry was posted on September 6, 2023 by Anne Helmenstine (updated on September 16, 2023)

How Many Bones Are in the Human Body — Learn how many bones are in the human body. Get the number for both adults and infants and learn why the number varies between people.

How Many Bones Are in the Human Body?

This entry was posted on September 5, 2023 by Anne Helmenstine (updated on September 16, 2023)

Planck’s Constant Definition — Learn what Planck's constant is and why it is important in quantum mechanics. Get the definition and value of h.

Planck’s Constant Definition and Value

This entry was posted on September 3, 2023 by Anne Helmenstine (updated on September 10, 2023)