Sir Alexander Fleming
(August 6 , 1881 – March 11, 1955) Early life and Education Sir Alexander Fleming was a Scottish physician, microbiologist, and pharmacologist, who was born on August 6, 1881 at Lochfield farm near Darvel, in Ayrshire, Scotland. Alexander was the third of four children of farmer Hugh Fleming (1816–1888) from his second marriage to Grace Stirling Morton (1848–1928). In December 1915, Fleming married a trained nurse, Sarah Marion McElroy of Killala, County Mayo, Ireland. Their only child, Robert Fleming (1924–2015), became a general medical practitioner. After his first wife’s death in 1949, Fleming married Dr. Amalia Koutsouri-Vourekas, a Greek colleague at St. Mary’s, on 9th April 1953; she died in…
True Or False On Carbohydrates
Movement of Substances Quiz
Diffusion – Movement of Substances
Table of Contents Diffusion Defination Diffusion is the net movement of molecules and ions from a region of their higher concentration to a region of their lower concentration down a concentration gradient, as a result of their random movement. What is Diffusion The molecules of a gas such as oxygen are moving about all the time. So are the molecules of a liquid or a substance such as sugar dissolved in water. As a result of this movement, the molecules spread themselves out evenly to fill all the available space (Figure). Diffusion This process is called diffusion. How are substances transported by diffusion? One effect of diffusion is that the…
Blood vessels and their functions
Arteries are blood vessels which carry blood away from the heart. They have thick, muscular and elastic walls that can withstand the surge of the high-pressure blood pumped out of the heart.