Cellular respiration converts the energy of fuel molecules to a form of energy that a cell can use to perform work. in an average day, most adult humans need to consume about 2,000 calories to maintain their health. however, the exact amount of dietary calories a person needs depends upon many factors, including the person's age, physical activity, size, and health. foods that we consume vary greatly in their nutritional content and quality. a large hard-boiled egg, for example, has about 75 dietary calories and contains about 70% of our recommended daily intake of cholesterol. a. molecules that come from the food we eat provide energy for the amazing work that goes on inside of our cells. this energy, stored inside of our food, is a form of . if a person eats one hard-boiled egg and digests the egg fully, cellular respiration will convert most of this energy into . the amount of dietary calories in one hard-boiled egg could raise the temperature of

Science27 of the most iconic, jaw-dropping photos of the earth and the moon from spacedave mosher  oct 1, 2018, 11: 13 am etnasa/flickrapollo 11 astronauts took this photo of earth on july 20, 1969.from the ground, earth looks like a boundless fertile plain that beckons to be explored and exploited.but astronauts would beg -  and even plead  - to differ."you realize that people often say, 'i hope to go to heaven when i die,'" jim lovell, an astronaut who flew on the apollo 8 and apollo 13 missions to the moon, previously  told business insider. "in reality, if you think about it, you go to heaven when you're born."lovell has seen first-hand that we live on a tiny rock hopelessly lost in the void. he's also quick to tell you it's the only one we've got - a  fragile spaceship  for more than 7 billion people: "you arrive on a planet that has the proper mass, has the gravity to contain water and an atmosphere, which are the very essentials for life. and you arrive on this planet that's orbiting a star just at the right distance - not too far to be too cold, or too close to be too hot - and just at the right distance to absorb that star's energy and then, with that energy, cause life to evolve here in the first place. in reality, you know, god has really given us a stage, just looking at where we were around the moon, a stage on which we perform. and how that play turns out is up to us, i guess."humanity has recorded photos of earth from hundreds, thousands, millions, and even billions of miles away, some of them taken by lovell himself.these images not only scientists study our dynamic world, but also understand how a habitable planet looks from afar, which aids the search for  more worlds. most importantly, however, the images underscore our peculiar existence on  a mote of cosmic dust.take a moment to ponder 27 of the most arresting images of earth that humankind has ever captured from space.a