Physiological adaptations are processes inside an organism's body, such as its biochemistry, metabolism and the way its organs work. They are often invisible from the outside.Examples in animals
• Hibernation: animals such as hedgehogs lower their metabolic rate and body temperature in winter, saving energy when food is scarce.
• Antifreeze proteins: some Antarctic fish make antifreeze proteins that stop ice crystals forming in their blood and tissues at temperatures below 0 °C.
• Water conservation: kangaroo rats rarely drink. They gain much of their water as metabolic water, released by respiration of the food they eat, and they produce very concentrated urine.
• High altitude: llamas have haemoglobin with a higher affinity for oxygen than that of lowland mammals, so their blood loads oxygen even where the partial pressure of oxygen is low.
• Snakes and spiders produce venom to kill or paralyse prey.Examples in plants
• Cacti and some other desert plants open their stomata at night, when it is cooler and more humid, and store carbon dioxide as organic acids to use in photosynthesis during the day. This greatly reduces water loss.
• Some plants make toxic or bad-tasting chemicals that deter herbivores.Examples in microorganisms
• Some bacteria produce enzymes such as penicillinase, which break down antibiotics, making them resistant.
• Some fungi and bacteria produce antibiotics that kill competing microorganisms.
• Hibernation: animals such as hedgehogs lower their metabolic rate and body temperature in winter, saving energy when food is scarce.
• Antifreeze proteins: some Antarctic fish make antifreeze proteins that stop ice crystals forming in their blood and tissues at temperatures below 0 °C.
• Water conservation: kangaroo rats rarely drink. They gain much of their water as metabolic water, released by respiration of the food they eat, and they produce very concentrated urine.
• High altitude: llamas have haemoglobin with a higher affinity for oxygen than that of lowland mammals, so their blood loads oxygen even where the partial pressure of oxygen is low.
• Snakes and spiders produce venom to kill or paralyse prey.Examples in plants
• Cacti and some other desert plants open their stomata at night, when it is cooler and more humid, and store carbon dioxide as organic acids to use in photosynthesis during the day. This greatly reduces water loss.
• Some plants make toxic or bad-tasting chemicals that deter herbivores.Examples in microorganisms
• Some bacteria produce enzymes such as penicillinase, which break down antibiotics, making them resistant.
• Some fungi and bacteria produce antibiotics that kill competing microorganisms.