embrión

Embrión is the term used to describe the early stage of development of a multicellular organism. In humans and other mammals, this stage begins after fertilization, when the sperm fuses with the egg to form a zygote. The zygote then undergoes rapid cell division and differentiation, forming a blastocyst and subsequently an embryo. This period is characterized by the formation of the major organs and body structures.

The embryonic period is a critical time for development, as it is during this phase that the foundations for all subsequent growth are laid. The developing embryo is highly sensitive to external factors during this stage, and disruptions can lead to congenital abnormalities. The duration of the embryonic period varies across species, but in humans, it typically lasts for the first eight weeks of gestation, after which the developing organism is referred to as a fetus.

During embryogenesis, cells specialize to form tissues and organs. This complex process involves intricate signaling pathways and genetic regulation. The development of the nervous system, heart, limbs, and other vital structures occurs during this period. Understanding embryonic development is crucial in fields such as medicine, biology, and developmental psychology.