Summary of Histología del tejido Muscular CAPÍTULO 7

00:00:00 - 00:30:00

This video discusses the histology of the muscular tissue, focusing on the differences between the muscle cells in striated and cardiac muscle. The striated muscle cells are composed of many small cells, while cardiac muscle cells have fewer, but larger cells. The histology of the cardiac muscle cell is illustrated with a pair of pants. The transversal and longitudinal cuts are then shown, illustrating how the different levels of the cell are revealed. Finally, the muscle cell types, striated and cardiac, are summarized.

• 00:00:00 This video discusses the histology of the muscular tissue, starting with the muscular cell. The muscle cell is surrounded by connective tissue and contains muscle fibers. The muscle fibers are surrounded by a sheath of connective tissue called the perimission. The perimission divides the muscle fiber into small fascicles, each containing muscle fibers and a small amount of connective tissue. The myofibrils are a group of filaments that are organized into bands and are embedded within the perimission. The myofibrils are surrounded by a sheath of connective tissue called the reticulum endoplasmic lasso. The reticulum endoplasmic lasso is responsible for storage of calcium. The myofibrils are also surrounded by a sheath of connective tissue called the sarcoplasm. The sarcoplasm is responsible for the contractile properties of the muscle fiber. The myofibrils are also surrounded by a sheath of connective tissue called the myofibril sheath. The myofibril sheath contains several different types of fibers, including thick and thin filaments. The myofibrils are also surrounded by a sheath of connective tissue called the sarcolemma. The sar
• 00:05:00 In this video, histology of muscular tissue is discussed. Fibrils are described as being made of myosine and actin, and they form an ordered structure that is going to be divided into various areas based on their thicknesses. We call this structure bands, and the band with the thinnest and widest fibrils is going to be called banda. The muscle with a star-like appearance is due to the presence of multiple, multinucleated cells called fibers. We will now look at striated muscle, which has a different arrangement of cells. Striated muscle has numerous, planar nuclei and periferal distribution. In this image, we can see that the nucleus is typically flat and has periferal distribution. We will now look at striated muscle under EM. We see that the nucleus is typically flat and has periferal distribution. We also see that there are some cells that are clearly outside of the membrane. These cells are called myofibrils. There are many myofibrils arranged in this way so that we can see them as a single unit if we emphasize this part that we mentioned earlier- that fiber is basically a cell and these cells have a particular arrangement. Striated muscle also has
• 00:10:00 This video discusses the histology of muscle tissue, specifically discussing the Satellite Cells that reside within it. Satellite Cells are responsible for the regeneration of muscle tissue, and in this particular example, the Satellite Cells are located within the muscle fibers. When we look at different muscle types, we'll discuss the regeneration process in more detail later. However, for now, let's say that a fiber or cell is the same in both Satellite Cell and Myoblasts phases. However, what happens is that some cells can differentiate and generate new fibers, which in turn can hypertrophy (grow larger). This process is called hypertrophy. At the same time, the cell can divide, but not itself by mitosis (cell division). This is called hyperplasia, and it does not involve hyperplasia, but rather there are cells called Satellite Cells that are responsible for the regeneration. We then grab this fiber and give it more growth, and we can see the bands as well as the electron microscope (EM). We then see the distribution of well-defined and poorly-defined cells, and we call this the Myofibril Arbor. Next, we use the electron microscope (EM) to see the triads (three components), which we will call the T
• 00:15:00 This video covers histology of the muscular tissue, specifically focusing on the darker parts of the tissue that are visible in the lighter parts. It discusses the periferal cells and their characteristic oval shape, as well as the central distribution of cells in cardiac muscle. The muscle is also distinguished by its striated appearance- which is due to the arrangement of cells in bundles. Finally, the video covers some of the capillaries in the muscle.
• 00:20:00 This video discusses the histology of the muscular tissue, focusing on the differences between the muscle cells in striated and cardiac muscle. The striated muscle cells are composed of many small cells, while cardiac muscle cells have fewer, but larger cells. The histology of the cardiac muscle cell is illustrated with a pair of pants. The transversal and longitudinal cuts are then shown, illustrating how the different levels of the cell are revealed. Finally, the muscle cell types, striated and cardiac, are summarized.
• 00:25:00 This video shows a cross-section of muscle tissue and illustrates the difference between the muscle fibers, which are fusiform in shape and long, and the plasma cells, which are sparse and located close to the nucleus. The video also discusses the muscle's involuntary nature and its functional units.
• 00:30:00 In this video, Leo discusses the different types of muscular tissue and their features. He then goes on to answer a question about which musclegroup has lost its extracellular matrix during contraction--and the answer is the smooth muscle, which corresponds to the central image in the slide show. Finally, Leo discusses the different types of nuclear features that can be found in muscle tissue, and offers a summary of what was discussed. He invites viewers to subscribe to his channel and leave feedback on the videos, and also recommends subscribing to the Mexican Society of Histology's channel for histology-related content.