Neuroderm is a specialized region of the ectoderm that gives rise to the nervous system, while ectoderm, endoderm, and mesoderm are the primary germ layers.

Gene expression, particularly the activation and repression of specific genes, plays a crucial role in determining the fate and differentiation of cells during development.

Shh signaling, particularly the gradient of Sonic hedgehog protein, is critical for establishing the dorsal-ventral axis and patterning the neural tube during vertebrate development.

Apoptosis is a tightly regulated process that eliminates defective or unwanted cells during development, ensuring the proper formation and function of tissues and organs.

Down syndrome, maternal rubella infection, and fetal alcohol syndrome are all known causes of congenital heart defects, highlighting the impact of genetic and environmental factors on developmental abnormalities.

Teratology is the branch of science that focuses on the study of birth defects, their causes, and the mechanisms underlying their development.

Thalidomide, a drug once prescribed for morning sickness, is a well-known teratogen that caused severe birth defects, particularly phocomelia, in the 1950s and 1960s.

The organogenesis stage, which occurs during the third to eighth weeks of human gestation, is the most critical period for teratogen exposure, as this is when major organs and structures are formed.

Autism spectrum disorder is a neurodevelopmental condition that is not typically considered a developmental abnormality in the same way as physical birth defects like cleft lip and palate or spina bifida.

Tissue regeneration involves the activation of stem cells, migration of cells to the site of injury, and cell division to replace damaged tissue.

Premature birth, genetic disorders, and environmental toxins can all contribute to developmental delay in children, highlighting the complex interplay of factors that can affect development.

Molecular embryology focuses on understanding the molecular mechanisms that regulate embryonic development, including gene expression, signaling pathways, and cellular interactions.

Folic acid deficiency, maternal diabetes, and alcohol consumption are all known risk factors for neural tube defects, emphasizing the importance of prenatal care and healthy lifestyle choices.

Cellular differentiation involves the acquisition of specialized functions and structures, allowing cells to perform specific roles within tissues and organs.

Autism spectrum disorder is a neurodevelopmental condition that is not typically considered a congenital anomaly in the same way as physical birth defects like cleft lip and palate or clubfoot.