Best Answer: Using single quotation marks around a word or phrase instead of double quotation marks is the standard way of indicating a quotation in British English. In normal, modern British English one uses single quotation marks, with double quotation marks reserved for a quotation within a quotation.
tubular secretion. the passage of substances from the blood in the peritubular capillaries to the tubular filtrate. Functions of tubular secretion. elimation of waste products not filtered by the glomerulus and regulation of the acid-base balance in the body through the secretion of hydrogen ions. what happens to the protein bound substances entering the peritubilar capillaries.
Exocrine glands are classified according to whether the duct system is unbranched (simple) or branched (compound), and according to the distribution of secretory versus ductile epithelium. If the duct and secretory portions are of uniform diameter, the gland is tubular.If the secretory cells form a dilated sac at the end of the duct, it is acinar, and if the secretory cells extend uniformly from the duct then form a sac, it is called tubuloacinar.f the duct and secretory portions are of uniform diameter, the gland is tubular. If the secretory cells form a dilated sac at the end of the duct, it is acinar, and if the secretory cells extend uniformly from the duct then form a sac, it is called tubuloacinar.