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.
Pseudo Stratified epithelia consist of a single layer of cells where all cells are in contact with the basement membrane but do not necessarily have an apical surface. 7. How do the prefixes exo- and endo- give you a clue to the function of exocrine and endocrine glands? exo- means “outside” which refers to these glands secreting their products into ducts that empty onto the surface of a covering and lining epithelium; endo- means “inside” which refers to these glands secreting their products into
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.
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.
The lymph vessels collect fluid, called lymph from the body tissues and return it to the blood, maintaining the fluid balance within the body. Lymph filters through the lymph nodes, which are packed with white blood cells known as lymphocytes. These are produced in the bone marrow, spleen and thymus, and they help to protect the body against infections. Spleen: This is the largest lymphatic organ. It is located on the left side of the body just above the kidney.
P2 Outline the Main Tissues Of The Body Epithelial Epithelial tissue is basically the linings of both the internal and external surfaces of the body and can be divided into two groups. The groups depend upon the number of layers of which it is composed. These two groups are simple epithelial and compound. Simple squamous are thin, flat plates and their main function is osmosis (which is the passage of water molecules from a region of low concentration to one of high concentration through a semi-permeable membrane) and diffusion (which is the passage of molecules from a high concentration to a low concentration). They form the lining of cavities such as the mouth, blood capillaries, heart and lung alveoli and make up the outer layers of the skin.
Single membrane compartment organelles include the endoplasmic reticulum and Golgi apparatus. Ribosomes don’t have a membrane. The breakdown of the membranes of these structures affect the function of the heart because lysosomal enzymes are normally bound safely inside vesicles that will digest the plasma membranes and the membranes of the organelles. Question D: Two important pieces of information- The instructions Joseph’s body needs to repair itself and his predisposition for vascular disease-are both contained within the cell on which structures? (A) Joseph’s predisposition means that he inherited vascular disease which is held in the
A drug administered systemically relies on the circulatory system to take it to the site of action and to other tissues in the body. After absorption into blood, most drugs must leave the bloodstream and enter the site of action to exert their effect. For a drug administered topically (nonsystemically), entry into or exit from the blood is not necessary. Topical drugs merely need to travel a short distance from the site of administration (i.e., the skin surface for dermal administration) to the site of action (i.e., dermis). However, it is possible for topical drugs to enter the systemic circulation and cause side effects.
These properties come from the way charges are distributed across the molecule. Thus, the role of the phospholipids is to make sure that water-soluble substances do not enter or leave the cell, and they allow lipid-soluble substances to enter or leave the cell. However, a simple phospholipid bilayer cannot perform all of the cell’s functions by itself; it is too fragile to function as a barrier within/around the cell, and other components are needed to help its function. The term ‘fluid mosaic’ is used to describe the arrangements in the membrane, and the main features are (aside from the bilayer of phospholipid molecules): * Protein molecules floating in the bilayer, either freely, or bound to other structures * Extrinsic proteins partially embedded in the bilayer on the inside or outside; other intrinsic proteins completely spanning the bilayer In addition, the cell surface membrane is impermeable to
Hormones regulate various human functions, including metabolism, growth and development, tissue function, sleep, and mood. The field of study dealing with the endocrine system and its disorders is endocrinology, a branch of internal medicine. Features of endocrine glands are, in general, their ductless nature, their vascularity, and usually the presence of intracellular vacuoles or granules storing their hormones. In contrast, exocrine glands, such as salivary glands, sweat glands, and glands within the gastrointestinal tract, tend to