By: Crash Course Biology
Hank takes us on the fascinating journey through our excretory system to learn how our kidneys make pee.
By: Bozeman Science
Paul Andersen explains how organisms regulate their internal osmolarity or not. He starts with a brief description of osmosis and why it is important for animal cell to be surrounded by an isotonic solution. He then explains how freshwater and saltwater fish osmoregulate. He finally discussed the nephron within the kidney as an osmoregulatory organ. He explains how the loop of Henle sets up a gradient which is used to reclaim or remove water with the use of the antidiuretic hormone (or ADH).
By: Bozeman Science
Paul Andersen explains how organs work together to form organ systems and how organ systems work together to form organisms. The kidney and bladder work together to filter blood in the excretory system. The circulatory and respiratory system work together to bring oxygen and nutrients to the cells. A quick survey of the major organ systems is also included.
By: Bozeman Science
Paul Andersen explains how hugs between tissues can help maintain homeostasis. Countercurrent heat exchange allows heat to stay within the core of the body. Close contacts between the capillaries and alveoli allow our body to maintain the correct concentration of oxygen. Capillaries also hug the tubules in the nephron to maintain osmolarity and filter the blood. Hugs in the gills of a fish allow them to maintain an adequate amount of oxygen in an oxygen-poor environment.
(feel free to ask questions about them in class)