Embryo Tales

Learning About Embryology

Embryology starts with the study of embryos and their development. It also includes all aspects of reproduction and related health as well. Scientists are still learning new things about reproduction and development every day. Embryo Tales are stories about this broad area of science.

Embryo Tales are based on articles that are a part of the Embryo Project, which is an encyclopedia on all things embryology and reproduction. In these Embryo Tales, you may find stories on tissue development, menstruation, sex chromosomes, what it means to be intersex, the history of reproductive biology, and much, much more.

If you want to take a step further and learn more about any of these subjects, look on each story page for the links to the Embryo Project articles on which they were based.

Special thanks to Arizona State University's Center for Biology and Society and to the editors who have helped create these stories: Dina Ziganshina, Risa Schnebly, Emily Santora, and Dr. Biology.

"Autism" written in chalk on a blackboard

All About Autism

Written by: Nathaniel Ross

You may have heard of autism before, but do you know what it really is? Learn about what it’s like to live with autism.

A scientist wearing thick blue gloves uses tongs to dip test tubes into a bath of liquid nitrogen. Steam rises from the cold-looking liquid.

Cells, Frozen in Time

Written by: Risa Aria Schnebly

If a living organism freezes, it can die. But by freezing living cells at just the right temperature, scientists can preserve living cells instead of killing them.

Confronting Human Chimerism

Written by: Tazeen Ulhaque

Most people have just one set of DNA throughout their body. But what happens to humans who are born with two sets?

Three mice on a blue blanket. The mouse on the right has one red eye and one black eye, showing that it is a chimera.

Creating Chimeras

Written by: Tazeen Ulhaque

Most organisms have just one set of DNA. So why would some scientists want to work with or create organisms that have two sets of DNA?

An illustration of a female reproductive system with a ruptured fallopian tube with red blood drops coming out of it

Ectopic Pregnancy: An Unexpected Path

Written by: Logan Hunt

Pregnancy isn’t perfect, and many things can go wrong. What happens when a growing embryo is in the wrong part of the pregnant person's body?

crossed out silhouette of a pregnant woman reading "no alcohol"

Fetal Alcohol Syndrome and Pregnancy

Written by: Logan Hunt

Have you ever noticed that most people do not drink alcohol while pregnant? Let’s learn about why doing that is so important.

Focusing on Female Infertility

Written by: Emily Santora

What happens when a person wants to have a baby, but after years of trying, it just doesn’t happen? A lot of people want to become pregnant, but let’s learn about what may prevent pregnancy.

Four colorful striped flags representing the gender fluid, agender, non-binary, and trans people.

Gender Identities and Expression

Written by: Risa Aria Schnebly

There are more genders than just “man” or “woman” that a person can identify as. Let’s explore a variety of gender identities and learn about their history.

An illustration of rainbow figures with symbols typically associated with being male or female mixed up to indicate a diversity of sexes and genders.

Gender Versus Biological Sex: What’s the Difference?

Written by: Risa Aria Schnebly

You might have heard of both gender and sex before, but what’s the difference? Sex is based in the biology of body parts, but gender is socially constructed and based on much more.

Getting to Know the Germ Layers

Written by: Claudia Nunez-Eddy , Risa Aria Schnebly

Almost all life forms start out as small cells, but how do they grow into entire animals? Read about the first step here: when cells in an embryo form germ layers that give rise to every organ and tissue in the body.

Someone raising their arm to show off armpit hair

Helpful Sex Hormones

Written by: Risa Aria Schnebly

Our biological sex is mainly controlled by our sex chromosomes. But sex hormones also influence what body parts and characteristics we have.

An ultrasound showing a blurry image of a fetus.

How Fast Do Embryos Grow?

Written by: Megha Pillai, Logan Hunt

We start off as a single tiny cell, and yet somehow we are born as whole humans. Get to know the stages of that process and how quickly we develop.

An intersex pride flag, showing a purple circle on a yellow background

Intersex: More than Male and Female

Written by: Risa Schnebly, Riley McInnis

You might think that people can be born only as either males or females. In fact, lots of people are born with a blend of male and female traits. We call this being “intersex,” and it happens more often than you may think.

A small T shaped piece of plastic resting in an open palm

Introducing the IUD

Written by: Molly Jacobson

Doctors place Intrauterine Devices (IUD) in the bodies of some females to help prevent pregnancy. Learn about how these devices work and how long they’ve been around.

Menstruation Matters

Written by: Emily Santora

Periods are a natural, normal part of life, and many people around the world experience them. So let’s talk about why and how they happen.

A woman clutching her abdomen, experiencing period cramps.

Periods: What Should You Expect?

Written by: Emily Santora

Sometimes things don’t work as you expect them to, including periods. Learn more about what causes some girls to have irregular or painful periods.

Plan B One-Step Emergency Contraception packaging

Preventing Pregnancy with Plan B

Written by: Molly Jacobson

Is there any way to prevent pregnancy after sexual intercourse? Learn about Plan B, an emergency contraceptive.

Shedding Light on Endometriosis

Written by: Emily Santora

A lot of illnesses, like colds, have very visible symptoms, but other conditions are not so obvious. Learn about how people spot and treat a condition called endometriosis.

A side view illustration of the internal female reproductive system

Summarizing Sex Traits

Written by: Risa Aria Schnebly

Our biological sex affects the way we look in some obvious ways, like deciding what body parts we are born with. But, it also has effects on a range of other sexual traits that you might not expect.

An image of ovaries in a person with PCOS. The image features an external look at a bumpy ovary attached to the rest of the female reproductive system, as well as a close-up, detailed look at the cysts within the ovary.

The Mysterious Case of the Missing Periods

Written by: Emily Santora

Estrogen and testosterone are two hormones that cause puberty. But what happens when the body doesn’t produce the amounts of hormones that it usually does?

Embryo Tales are created from encyclopedia articles that are a part of the Embryo Project.

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Embryo Tales

Learning About Embryology

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