Explain why large animal eats less food and utilizes less oxygen per gram of body weight than does a small ani
368677
maybe because they are less agile than that of a smaller animal there by needing only to consume such quantity of food, and also bigger animals has the ability to conserve energy in their body......i guess
45675
There are two issues here. One is that the body shape of ruminants and herbivores in general is very different from ours. If you think about it, their trunks aren't fat, but rather their legs are proportionally thin; that's the typical body shape for good runners such as ungulates (hoofed mammals) which they are.\nIn addition, mammals that are herbivorous and feed specially on grass tend to have large abdomens. That is only partially related to the number of digestive compartments they have (think of a leaf-eating gorilla compared with a slimmer omnivorous baboon); usually their intestine is extra long because they need more absorptive surface, as leaves are not the most nutritious and easy-to-digest food.\nA side note: cows don't have 4 stomachs; only the last of those cavities is equivalent to our stomach (i.e. glandular, with enzyme secretion) whereas the other 3 are often considered as subdivisions of the esophagus. \nAll that being said, a pampered cow that ingests more energy more than what it spends, will get as fat as a cow ;)
106622
Land animals can walk on land and breath oxygen. With the exseption of dolphins and whales the others cant breath oxengen.
541514
Pound for pound, there isnt anything to compare to meat (assuming of course you are adding in the fat, and the tasty, ever-surprising intestines and stomachs of the prey).  But, food for a carnivore is dangerous-you cant get fat and slow, you want to keep the meal frequencies to a minimum, and each meal comes with some exercise-thus big canivores only eat once or twice a week at best.  Herbivores eat for hours and hours every day.  No, the food is not highly nutritious, especially in terms of fat and protein content-but there is a whole lot of it, a long time to eat and digest it, and no worries about over-eating and getting fat, really.  You know, the eating patterns are why herbivores tend to be much more aggressive, dangerous animals that carnivores- Think bull moose, bull elephants, hippos, rhinocerous etc- They are much more aggressive and dangerous to be around than a corresponding lion or wolf.  Herbivores can afford to get quite injured, and still recover cause their food doesnt move around and try to get away.  A tiger breaks it's foot, or gets a terribly torm muscle, and it will likely starve, so large carnivores are generally very wary of getting into fights.
235068
The first is surface area. The mammalian lung has a huge number pf alveoli compared to lung structures of reptiles and amphibians. The greater the surface area available for gas exchange, the more efficient will be the gas exhange.\n\nThe second requirement for gas exchange is assisted by the mamallian heart of four chambers as opposed to reptilian and many other hearts. There is an enormous amount of the circulatory system that passes directly to the pulmonary arteries and veins. Thus there is sufficient blood circulation in the lung area to remove oxygen and transfer it to the rest of the body.\n\nComparative biology will show far fewer alveoli in non-mammalian hearts (with the exception of birds). The other thing notable from compataive anatomy is that the mamallian heart (and that of birds) is a four chambered pump that does not mix unoxygenated blood with blood that has been oxygentated.\n\nSurface area and increased opportunities for deoxygenated hemoglobin to accept oxygen due to more efficient heart action.
422957
It does vary from species to species and individual to individual.  Larger ones can last longer than smaller.\n\nAll of them can last much longer than you'd think.  Cold-blooded animals don't burn through oxygen like wasteful mammals and birds do.
11899
Venturing a guess here:\n\nCholesterol hardens you veins, and birds, due to the energy requirements of flight, need incredibly high blood pressure.  Bird lungs have a seperate entrance and exit, unlike mammalian lungs where CO2 goes out the same way O2 comes in.  The higher effeciency is necessary to power the large pectoral muscles.  I'd imagine that if there oxygen demands were that high, they'd need some strong blood vessels to carry their blood at high pressure.
827670
Decrease because there is less oxygen. I think.
791055
it is impossible to answer the first question since at the big bang there was at lest the first  thousand years no atoms.\n\nMany animals  need oxygen  for their need in energy. But for some bacteria oxygen is a poison\n\nOxygen is important to animals since the nervous cells  die quickly without oxygen
192733
Cows have a two stage digestive system, like many animals that eat grasses. Because they consume so much grass and it is so hard to chew, they first swallow it to a pouch above their stomach.  Bacteria begins to breakdown the grass, much like fruit ferments, in that pouch.  Once it softens enough to chew, and the cow will regurgitate the cud (food) from the pouch to its mouth, chew it and swallow it to their stomach where it is digested much like ours.\n\nWe, birds and fish all have much more efficient digestive systems and so don't need to consume as much.  Also our diet has much more variety and food value.
945461
The sheep/deer. These are herbivores and both ruminants. Digesting grass is tough work and you need a lot of intestine to do the work. The average human has a small intestine arouind 20 feet long. A horse, by comparison, has a digestive tract that is 100 feet long.
659354
Dead plants and animals cannot be said to occupy a level in the food chain as being dead they are not able to eat and therefore occupy the lowest space on the trophic level  as food for fungus, microbes, insects, animals and other plant life.\n\nStrange question.
1145700
Whales are fat primarily because they eat massive amounts of  food that contains a lot of fat.\n\nAnd before anybody tells you that whales aren't fat, let me assure you that they are. A wild whale has about the same body fat as a fattened domestic pig. \n\nWhales need that fat because it streamlines their body, making it easier to swim, and to keep them warm in the cold waters in which they live.\n\nFemale whales need a lot of fat because they often go without eating for 3 months or more when they give birth as they swim to warm water breeding grounds where there is no food.
755323
Because the absorption of food is reduced due to the lessened time it has in the small intestine.  The shorter the intestine, the less the absorption.  The less the absorption, the fewer calories which are taken into the body.  The fewer the calories, the increased opportunity for weight loss.
856519
I can't answer - sorry. I don't know what the question is.  Carabao are big heavy buffaloes well adapted to living in swamps. There are any number of reasons why they might need to push harder on the ground at one time rather than some other time ( for example if they are standing in shallow water rather than up to their shoulders, less of their body weight would be bouyed up by the mass of water displaced). \n\nPush harder on the ground than what?
767505
Birds and fowl lack smooth muscles in their throats to pull food and water down to their stomach.  Therefore they have to lift up their heads and let it fall.  This is why you can't bring a canary in outer space because it would starve/dehydrate.
568737
the air is lower pressure at higher altitude which means it is thinner, so there is less oxygen. if they already have trouble getting enough oxygen, then they will have much more trouble.