Compounds called proteins and phospholipids make up most of the cell membrane. The phospholipids make the basic bag. The proteins are found around the holes and help move molecules in and out of the cell. Cell Membrane A cell membrane of the cell. It gives the cell its shape, it is the outer covering of the cell made up from phospho-lipid-protein bi-layer, which allows the materials to enter and to exit.
5. A) provide support for the overlying epithelial tissue B)The basal lamina secrete glycoproteins and the fibroblasts of the reticular lamina contains collagen proteins 6. The covering and lining epithelia may be layered as single, pseudostratified, or stratified. The three basic cell shapes of the covering and lining epithelia are squamous, cuboidal, and columnar. 7.
Several molecules make matter - organelles. Organelles metabolized and work together to make cells. Cells make tissues and a minimum of 2 tissues, usually four types make an organ. The organs work together in certain organ systems. Multiple organ systems make the organism.
Cells are also capable of communication (hormones from endocrine gland cells & neurotransmitters from nerve cells binding to receptors) & defence (proteins – antibodies, bind to harmful substances – antigens & carry out actions to make them harmless. 2. Describe what Protoplasm is. Protoplasm is the living centre of a cell surrounded by plasma membrane. It is the entire substance of the cell.
Epithelial cells that produce secretions are called gland cells. Individual gland cells are scattered with other cells in an epithelium. In a glandular epithelium, most or all of the cells produce secretions and they are discharged as “exocrine”. Exocrine is discharged onto the surface of the epithelium. “Endocrine” secretions are released into the surround tissue fluid and blood.
P2 There are two different types of epithelial tissue these are simple and compound. Simple Epithelium- this type of epithelium tissue is from an animal consisting of one of more layers of closely packed cells. The cells can vary in structure depending on their function which may be protective, secretory or absorptive. This epithelium tissue covers external and internal surfaces of the body. Compound Epithelium – this type of epithelial tissue is made to withstand wear and tear.
These cells, too small to be seen with the unaided eye, are organized into tissues. A tissue is a series of cells that accomplish a shared function. Tissues, in turn, form organs, such as the stomach and kidney. A number of organs working together compose an organ system. An organism is a complex series of various organ systems.
There are a number of cell junctions used by the various tissue types for contact with surrounding cells and the basement membrane, communication and for structural integrity. The contrast of the functions of each tissue is that some are striated and some are unstraited. Ref: http://www.ivy-rose.co.uk/HumanBody/Tissue/Tissue_Muscular-Tissue.php 2.Our body contains four different membranes (physical barriers), each with a specific function. Understanding their different roles and functions, please describe what you think would happen to the body if each was damaged? If each membrane is damaged, the epithelium would not be able to be held up because the lamina propia is what supports the epithelium.
Epithelial tissues line the cavities and surfaces of structures throughout the body, and also form many glands. Functions of epithelial cells include secretion, selective absorption, protection, cellular transport and detection of sensation. Epithelial layers are avascular, meaning they contain no blood vessels and rely on underlying vascular tissues to absorb nutrients from. Epithelia can also be organized into clusters of cells that function as exocrine and endocrine glands. Exocrine and endocrine epithelial cells are highly vascular.
They are bean-shaped, approximately 1 – 25 mm long, and act as a lymph filter. They are positioned in groups in specific regions of the body and named after that region, eg. inguinal (groin) and axillary nodes (arm) (Rhoades et al 2003). The node’s outermost layer is the capsule, dense connective tissue covering the node, which extends into it in extensions called trabeculae that section the node into compartments, providing structural support and a route for blood vessels to enter the node, via which B and T cells can also enter (Milling n. d.). Deep to the capsule is a network of reticular fibres and fibroblasts which, with the capsule and trabeculae, make up the stroma.