Introduction About what is Embryology

Embryology refers to the branch of biology which deals with the principles of the embryos from the stage of ovum fertilization till their development. It is the developmental process of a single cell, embryo to a baby within an average of 266 days or 9 months. However, it is the parental development of an embryo and fetus. Karl Ernst Von Baer is known as the Father of Embryology. He was an Estonian professor studying embryos and development. when he made the discovery that leads the foundation of modern comparative embryology. Embryology helps to understand the relation between the organ system such as the nervous system and muscle.


The process by which the embryo is formed and developed into a fetus is called Embryogenesis. The pre-embryogenesis begins with the fertilization of the ovum by sperm. The fertilized ovum is referred to as a zygote that undergoes active mitotic cell division without significant growth and cellular differentiation, leading to the development of an embryo. In mammals, this term refers to the early stages of prenatal development of the fetus.

Human Development 

It is a complex process by which a single cell gives rise to a highly developed multicellular human being. The process begins when an oocyte (ovum) is fertilized by a sperm to form a zygote, which differentiates into a definite organ system and then into early transformations through the help of various different processes such as cell migration, growth cell differentiation, apoptosis, cell rearrangement.

Essential Healthcare-strategies 

  • Prenatal diagnosis and surgical treatment.

  • Therapeutic procedures for infertility.

  • Mechanisms to prevent birth defects.

Duration And Stages Of Pregnancy

Gestation in humans lasts for an average of 266 days (38 weeks, 9 months). 

It is divided into three-month intervals called trimesters.

First Trimester (First Three Months, Weeks 1 to 12 Weeks)  

The most threatening symptoms during this stage are embryonic development stress and nutritional deficiencies. Morning sickness is also co-related with this critical period and has the infertility advantage of making mom less likely to ingest potentially dangerous materials including Cabbage, Brussel sprouts, Potatoes, Overcooked meat, etc. All of these contain poisons which can be harmful to the embryo.

For Example Coffee contains over 1000 different toxins.

Second Trimester (Second Three Months, Week 13 to 24)

During this period, fetal development begins, organs complete most of their development.

Third Trimester ( Third Three Months, Week 25-Birth)

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Baby continues to grow and mature throughout this stage. Baby can stretch itself, kick at this stage followed by other movements. There is huge development during thirty weeks in the baby's sense organs, fingers, nails are visible, bones get hardened, the formation of red blood cells ( RBC’s) is seen in the bone marrow. 


Different Types Of Embryology

  • Descriptive Embryology 

The Descriptive Embryology can be defined as the study concerned with the direct observation and description of embryological development.

  • Comparative Embryology

Comparative embryology can be defined as the embryological development of different species. This paves way for understanding evolution and phylogenetic significance in a much more relevant manner.

  •  Experimental Embryology

This branch of embryology is also called as Casual embryology or Analytical Embryology.

In the Experimental Embryology, the embryos are experimented for studying the various developmental stages. It also helps to understand the fundamental mechanisms of the organisms. The embryos are dissected and the various parts of the embryo are removed, transplanted and even the environmental conditions are altered. 

  • Chemical Embryology

Chemical Embryology can be explained as Embryology which deals with biophysical, biochemical, and biological techniques. It is also called as Physiological or Biochemical Embryology.

  • Tetralogy

It is a branch of Embryology which deals with the malfunctions of the embryo.

FAQ (Frequently Asked Questions)

1. How Does Embryology Provide Evidence For Evolution?

Evolution is the study of how different types of living organisms numerous change over time. Evolution Evidence and Embryology work in tandem to support the theory that all forms of life are evolved from a common ancestor, it is like answering a question of why you had a tail before you were born.

Charles Darwin and Alfred  Wallace in the mid of 1800s, independently concluded that inherited variations in traits, such as bird’s beak shape may provide better odds of survival in a given niche. Without the advantageous variation, organisms are less likely to survive and pass on their genes. Different scientific evidence has been emerged supporting the theory of evolution, which includes embryology. 

2. What Is The Difference Between Developmental Biology And Embryology?


Embryology is a subset of developmental biology. It is only concerned with the development of Embryo. Embryology focuses on the development from one uninitiated cell to a complete organism. The development of the embryo takes place during the early stages of pregnancy. The gestation period is about nine months or 40 weeks. 

Development Biology

Developmental biology is a part of science. Developmental biology deals with the study of various actions involved in the development of living organisms. Developmental biology especially include examples like tail loss and other changes in the tadpole of frog and the biology of the imaginal discs, which generate the adult body parts of the fly Drosophila.