tubules in Biological Definition

Kidney

... the water in the filtrate enters the convoluted tubules and collecting ducts by osmosis. Fluid flows ... Fluids become more concentrated along the tubules and ducts to form urine , which is then drained ... medulla. They contain the secreting apparatus and tubules and are also called malpighian pyramids . ...

Excretion

... salt through the tear ducts associated with the eyes. Such birds can drink sea water without harm. In insects , a system involving Malpighian tubules is utilized to excrete metabolic waste. Metabolic waste diffuses or is actively transported into the tubule, which transports the wastes to the ...

Marcello Malpighi

... him, including a skin layer (Malpighi layer ) and two different Malpighian corpuscles in the kidneys and the spleen , as well as the Malpighian tubules in the excretory system of insects. He also studied chick embryo development with detailed drawings and discovered taste buds of human ....

Sperm

... cell is characterized by a minimum of cytoplasm. Sperm production Main article: Spermatogenesis Sperm are produced in the seminiferous tubules of the testes in a process called spermatogenesis. Round cells called spermatogonia divide and differentiate eventually to become sperm. During ...

Spermatogenesis

... and capacitation (initiation of the acrosome reaction) of the sperm cells so viability is maintained. Spermatozoa are produced in seminiferous tubules in the testes . They start off as spermatogonia , undergoing mitosis becoming a type A spermatogonium or a type B spermatogonium. Type B ...

Tumor

... cell carcinoma basal cell (only in skin): basal cell carcinoma glandular epithelium: adenoma , cystadenoma , adenocarcinoma tubules epithelium (kidney): renal tubular adenoma , renal cell carcinoma (Grawitz tumor ) hepatocytes: hepatocellular adenoma , hepatocellular ...