Поиск
Озвучить текст Озвучить книгу
Изменить режим чтения
Изменить размер шрифта
Оглавление
Для озвучивания и цитирования книги перейдите в режим постраничного просмотра.

STRUCTURAL ORGANIZATION OF THE HUMAN BODY

The human body is composed of cells and non-cellular structures which consistently united in tissues, organs, organs' systems and the human body as a whole during the process of philoand ontogenesis. A cell (cellula) is an elementary genetic, structural and functional unit, the main structural element of all living organisms (Fig. 5). A surface apparatus, cytoplasm and nucleus are the components of a human body cell.

The surface apparatus of a cell includes the cell membrane, surface specializations (specialisationes superficiales) or the supramembrane complex and submembrane structures. The cell membrane, plas-malemma (membrana cellularis, plasmalemma) is composed of the biphospholipid layer and protein molecules which are either on its surface or penetrate it (Fig. 6). Intracellular membranes have a similar structure. A supramembrane layer is termed the glycocalyx (glycocalyx) consisting of carbohydrate molecules (residue) associated with the proteins. This is a receptor unit of a cell. A sub-membrane complex is formed by an ectocytoplasm, cortical cytoplasm (ectocytoplasma) which contains microtubules and microfilaments composed of protein structures that act as the cytoskeleton. The surface apparatus of a cell provides the transmem-brane transport of substances into and out of the cell.

The cytoplasm (cytoplasma) contains the cytosol (cytosol, matrix cytoplasmatica), organelles and cyto-plasmic inclusions (organella et inclusiones cytoplas-micae). The cytosol is a colloidal solution, the internal environment of the cell where all metabolic reactions occur. The organelles are permanent structures of a cell; they have a specific structure and perform certain functions. They include the ribo-somes, endoplasmic reticulum, Golgi complex, lysosomes, per-oxysomes, mitochondria, cyto-centre (centrosome).

Fig. 5. Structural organization and some principal organelles of a typical cell: 1 - cell membrane (plasmalemma); 2 - pinocytotic vesicles; 3 - centrosome (cytocentre); 4 - cytoplasm; 5 - endoplasmic reticulum: a - membrane of a rough endoplasmic reticulum, b - ribosomes; 6 - connection of the perinuclear space with endoplasmic cavities; 7 - nucleus; 8 - nuclear pores; 9 - nucleolus; 10 - Golgi apparatus (complex); 11 - secretory vacuoles; 12 - mitochondrion; 13 - lysosomes; 14 - stages of phagocytosis

Для продолжения работы требуется Registration
На предыдущую страницу

Предыдущая страница

Следующая страница

На следующую страницу
STRUCTURAL ORGANIZATION OF THE HUMAN BODY
На предыдущую главу Предыдущая глава
оглавление
Следующая глава На следующую главу