Few people think that each stage of life has its own name. So, science knows embryonic and postembryonic development. These periods are very different from each other and have different characteristics. The article will discuss what kind of development is called postembryonic. You will learn the types of the period and features.
What development is called postembryonic?
The moment when the embryo leaves the membranes is a transition from the embryonic period to the postembryonic one. In the people this time is called birth. It is worth noting that in different living organisms this process is very different.
Types of development of a living organism
The postembryonic period can be characterized by two types of development. Science knows the direct and indirect transformation of a living organism.
Direct development
This type of transformation includes an organism that is very similar to an adult. So, postembryonic human development has a direct view. This also includes the development of animals and some reptiles.
After birth, the embryo is very much like an adult organism. However, it differs in size and lack of skills.
Indirect development, or metamorphosis
The postembryonic period may have an indirect appearance (metamorphosis). In this case, an organism appears from the membranes, which is very different from an adult. This includes some invertebrates, mollusks and reptiles. As an example, you can take an ordinary butterfly. The postembryonic development of the body in this case is characterized by being in the form of a larva. Only after that does the butterfly become like an adult.
Characterization of the postembryonic period (direct development)
As mentioned above, immediately after a new organism leaves the membranes, a new stage in development begins. Post-embryonic human development is divided into several stages. The final stage is puberty. Consider the main stages of the postembryonic period.
The first stage of development: from birth to six months
At this stage, the baby adapts to the new environment. He learns to hear and focus his eyes on certain things. Nutrition at this stage of development is exclusively liquid. The baby cannot yet eat adult food on his own and is completely dependent on his mother. Some children are faster in development than others. They move to the next degree of the postembryonic period faster. So, some babies in half a year can already stand, sit and crawl. However, these are only physical skills. Science does not yet know the case when a child at this stage began to express himself in an understandable adult language.
It is worth noting that many animals and reptiles that pass the direct path of postembryonic development live about the same. However, in them this period can pass much faster than in humans.
The second stage of development: up to one year
At this stage, the little man learns to sit crawling and walking. This level is characterized by the acquisition of physical skills. Also, the young body begins to gradually get used to new food. Many children at this stage begin to make new sounds. So they learn to speak in a language understood by an adult. If the child is developing faster, then at this stage he may already speak some words or even simple sentences.
Reptiles and animals in this period are already fully prepared for adulthood. They themselves can get their own food and are no longer dependent on adults.
Third Period: Growth and Learning
The human body is characterized by the longest postembryonic development. At this stage, the child can already take care of himself, but living with his parents is still very difficult. In ordinary life, children at this stage attend preschool, and then school facilities. They grow, develop and learn everything that is useful to them in adulthood.
Mammals and animals at this stage have completely passed the postembryonic period and are considered adults.
Fourth period: puberty
So, what kind of development is called postembryonic, you already know. In humans, it ends at about 16-20 years old. At this stage, important parts of the body begin to work. The pituitary gland and adrenal glands produce certain hormones. In women, the ovaries begin to function and menstruation appears. Men acquire puberty and are able to continue their race.
The post-embryonic period ends with the transition to adulthood. A person is already able to live independently and create his own family.
Indirect postembryonic development characteristic
As in the previous case, this development is divided into several main stages. Let's consider them in detail.
The first stage: after birth
Immediately after the body leaves the membranes, its further transformation begins. At this stage, the new individual is completely unlike an adult. She is very different in appearance and internal development.
Second stage: transformation
At this stage, there is a strong transformation of the new organism. Each type of living creature, it occurs in different ways. The individual becomes similar to an adult animal or mammal. However, many organisms at this stage still need care and protection. They cannot yet provide for themselves.
Stage Three: Skill Acquisition
Indirect postembryonic development has a final stage, which is characterized by the acquisition of certain skills. They will help the future organism to live independently and not depend on extraneous individuals.
Summary and conclusion
Now you know what development is called postembryonic. It is worth noting that indirect conversion occurs much faster than the direct postembryonic period.
Man undergoes the longest course of this stage. However, human skills can survive even in the most difficult conditions. This cannot be said of reptiles or animals. The development of man in the postembryonic period is monitored by some doctors: pediatrician, neurologist and others. The parents of the baby are also especially careful.
Everyone should know what a postembryonic period is. The initial data on this time are known even from biology lessons. It is such information that helps to develop your own world.