To understand an organism, it is essential to understand its levels of organization. The first level is the cell, in which we analyze the cell, that is, the functional and structural unit of living beings. The next level is fabric; then the organs; then the systems and finally the organism as a whole. THE Histology it is the part of biology that studies tissues and how they assemble to form organs and systems.
→ What are fabrics?
Tissues are structures formed by a set of similar cells, which act to perform the same function, and by the extracellular matrix. They are not found in isolation in our body, but are always associated with each other, forming organs and systems.
Mind Map: Tissues
* To download the mind map in PDF, Click here!
→ What are the fundamental human tissue types?
In humans, it is possible to find four types of tissue:
- Epithelial Tissue: Tissue formed by juxtaposed cells and a small amount of extracellular matrix. One of its functions is to coat the surface of the body and some cavities. This tissue is also responsible for the formation of the various glands present in our body.
-
Connective tissue: Unlike epithelial tissue, connective tissue has different cell types that are not juxtaposed, that is, the cells are not very close to each other. In this tissue, there is still a lot of extracellular matrix.
There are different types of connective tissue, the main ones being: the connective tissue itself, adipose tissue, hematopoietic tissue, cartilage tissue, bone tissue and blood tissue.
-
Muscle tissue: This tissue has elongated cells with an incredible capacity for contraction. This type of tissue is linked to our locomotion and nutrition, in addition to ensuring that the body's cells receive nutrients and oxygen.
There are three basic types of muscle tissue: cardiac striated muscle tissue, skeletal striated muscle tissue, and smooth muscle tissue.
Nervous Tissue: it is formed by cells whose main role is the transmission of nerve impulses. As the main cell of this tissue, we can mention the neurons.
→ Only animals have tissue?
In addition to animals, plants also have real tissues. These tissues also act to form organs in the plant, such as leaves and stems. The main plant tissues are: epidermis, parenchyma, collenchyma, sclerenchyma, xylem and phloem.
The epidermis is a lining tissue that protects the plant's body. The parenchyma, colenchyma and sclerenchyma are part of the fundamental system and act, for example, by supporting the plant and filling spaces in the organs. Xylem and phloem, on the other hand, are tissues that act in the transport of substances from the plant.
ATTENTION:Fungi, bacteria and organisms classified as protists do not have real tissue.
By Ma. Vanessa dos Santos
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/biologia/o-que-e-tecido.htm
