Fish remove oxygen from water using gills, specialized organs that aid in breathing. As water flows over the gills, they extract oxygen efficiently. This breathing mechanism allows fish to thrive in aquatic environments. Their efficient respiratory system enables them to take in maximum oxygen for survival. As water passes over the gills, oxygen from the … Read more

Fish remove sodium (Na) and chloride (Cl) using specialized cells in their gills. These cells actively excrete excess ions into the water. Fish also regulate these ions through kidney function and intestinal absorption. This process helps maintain body water balance and supports osmoregulation in different aquatic habitats. In contrast, seawater fish, such as tuna, reside … Read more

Fish remove carbon dioxide using their gills through diffusion. This process allows carbon dioxide to move from the bloodstream into the water. Carbonic anhydrase helps convert carbon dioxide to bicarbonate, which eases transport. This ensures effective gas exchange, balancing oxygen uptake and carbon dioxide removal in the aquatic environment. The gills contain thin membranes, which … Read more

Freshwater fish regulate water balance by excreting excess water through their kidneys. They reabsorb essential salts from urine to reduce loss. Special cells in their gills absorb salt from the surrounding water. This process, called osmoregulation, helps maintain their internal salt levels despite constant water intake. In contrast, saltwater fish live in environments with higher … Read more

Fish regulate their internal environment using osmosis. Marine fish have lower osmotic concentration than seawater, leading to water loss and salt gain. They actively excrete salt through their gills. Freshwater fish face excess water. They produce large amounts of dilute urine to maintain osmotic balance and regulate their internal environment. In freshwater, the surrounding water … Read more

Fish regulate their swim bladders to control buoyancy. They inflate it by taking in atmospheric air from the surface. Deep-water fish usually have a single-chamber swim bladder, called physoclistous. Their circulatory system manages this bladder, helping them maintain optimal depth without sinking. Conversely, when a fish needs to descend, it decreases the gas volume in … Read more

Fish regulate carbon flux by excreting carbon through feces and respiration. This process plays a key role in ocean carbon cycling. Research shows that fish excretions contribute about 16% of carbon that sinks below the ocean’s surface, removing roughly 1.65 billion tons of carbon from the atmosphere each year. Additionally, fish excrete waste that contains … Read more

Fish regulate salt by drinking seawater to stay hydrated. Seawater contains a lot of salt, so they need to remove the excess. They use their kidneys to filter blood and specialized cells in their gills to expel the surplus salt. This process, called osmoregulation, helps maintain a stable internal balance in their bodies. In contrast, … Read more

Fish regulate their metabolism based on their environment. As poikilotherms, their body temperature influences metabolic rates. Warm water increases metabolism, while cooler water decreases it. Their basal metabolic rate and oxygen consumption change according to the environmental temperature, resulting in significant variations in their metabolic processes. Fish with higher metabolic rates tend to require more … Read more

Fish regulate buoyancy with a swim bladder. When it expands, the swim bladder increases in volume. This causes more water displacement, helping the fish to float. When the swim bladder deflates, its volume decreases. This reduces water displacement, causing the fish to sink. This process allows fish to control their depth in the water effectively. … Read more