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Because of buoyancy. Buoyancy is a force caused by fluid pressure. Buoyancy can cancel out gravity, so that an animal living in the water does not even need limbs to support its body weight. Dolphins and whales, for example do not need any limbs. They have turned their front limbs into flippers and their rear limbs have almost disappeared entirely.
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What are the effects of low biochemical oxygen demand?
Low biochemical oxygen demand (BOD) in water indicates lower levels of organic pollutants, which can be beneficial for aquatic ecosystems by reducing the risk of oxygen depletion and promoting healthier water quality. It suggests that the water is less polluted and can support a greater diversity of aquatic life. However, very low BOD levels may also indicate poor nutrient availability for aquatic organisms.
What happens to aquatic organisms when the water is to warm?
There are many answers to this question. Warm water contains less oxygen so some aquatic organisms that get their oxygen directly from the water may not be able to survive, other organisms may grow rapidly in higher temperatures. This overgrowth could further deplete the available oxygen creating additional losses. If the temperature is high enough animals that didn't succumb to low oxygen levels may die of metabolic problems.
What is the difference between terrestrial biome and aquatic biome?
Differences between Terrestrial and Aquatic systemsbecause aquatic environments are so rich in nutrients they support more live than equivalent terrestrial ecosystems. The small drifting photosynthetic organisms of the oceans, referred to collectively as phytoplankton are regarded as the major photosynthesizers, or primary producers, of the earth,aquatic environments are much more stable than terrestrial environments, with smaller fluctuations in temperature and other variables,aquatic organisms are seldom exposed to desiccationwhile terrestrial organisms are often exposed to desiccation and are usually relatively resistant to drying out,oxygen (because there is very much less present) is sometimes a limiting factor an aquatic habitats but this is seldom the case in terrestrial habitats,light can be a limiting factor in some aquatic habitats, but in most terrestrial environments there is hardly ever a a shortage of light,terrestrial animals are influenced far more by gravity, while water supports aquatic organisms.
Why did whales return to the sea?
Whales returned to the sea from land because they evolved to adapt to the aquatic environment, where they found more food and less competition for resources.
Describe the 3 layers of bones?
The outer layer of bones is the compact bone, which is dense and provides strength and support to the skeletal system. The middle layer is the spongy bone, which is less dense and contains spaces filled with bone marrow where blood cells are produced. The innermost layer is the bone marrow, which produces red blood cells, white blood cells, and platelets essential for bodily functions.
Why breathing rate of aquatic organisms is faster than the terrestrial animals?
The breathing rate of aquatic animals is faster than that of terrestrial animals because the amount of dissolved oxygen in the water in much less than the amount outside, so they have to breathe more in order to get more oxygen
Why animals living in the water breath faster as compared to land animals?
because there are less amount of dissolved oxygen in water so that aquatic animals breathe more faster in order to get more oxygen.
Why are aquatic animals such as whales larger than terrestrial animals?
The breathing rate of aquatic animals is faster than that of terrestrial animals because the amount of dissolved oxygen in the water in much less than the amount outside, so they have to breathe more in order to get more oxygen
What things have a skeletal system?
less than the things that dont
What are the three nitrogenous waste excreted by animals?
The three nitrogenous wastes excreted by animals are ammonia (most toxic, released by aquatic animals), urea (less toxic, excreted by mammals), and uric acid (least toxic, excreted by birds and reptiles).
Does oil make an animal sink?
If by "oil" you mean petroleum (as opposed to olive oil) then YES, petroleum makes many animals, especially aquatic birds (like penguins and ducks) sink. The reason for this is that the petroleum sticks to their feathers giving them less maneuverability. As concerns aquatic mammals and fishes, the petroleum gets into their skin/scales and makes them less buoyant.
Do 100 bones make up the skeletal system?
i think no because we have 206 bones in are body so we can't have less bones in are skeletal system we cant have less than 206 bones
What are some microscopic animals?
Some microscopic animals include planarians (flatworms), numerous mites, including dust mites and spider mites, and aquatic crustaceans such as copepods and cladocerans (water fleas). The most numerous microscopic animals are nematodes(roundworms), rotifers (aquatic filter-feeders), and tardigrades (water bears).
What is the effect of environmental pollution and air pollution?
*It causes many diseases like Asthmas lungs cancer etc*By water pollution water will become very impure & it effects the life of aquatic animals & many aquatic animals will die also.*It effects the growth & development of plants
What are animals called that have no mouth?
Mouth-less animals.
How does ice protect aquatic animals?
Ice protects aquatic animals by isolating (ice is a good thermic isolater) the bottom of the pond from the atmosphere, and preventing the bottom of the pond from freezing and becoming ice.beause they are used to water
What are some disadvantages of animals being in World War 1?
because the animals would die! :( poor animals! also if they had less animals it would mean less meat and less advantage! i answered this cos i am awesome
