Answer:
The fish did not yet exist when the old layers of rocks were deposited. In fact, animals with hard parts did not evolve until about 600 million years ago, which is only about 13% of the 4.5 billion year age of the Earth. Multicellular animals without hard parts left tracks in older sediments, but had no fossilize-able body parts.
Explanation:
the three kinds of nitrogenous wastes based on the energy required to synthesize them are arranged; Ammonia < urea < uric acid.
Nitrogenous wastes are the nitrogen compounds that organisms use to get rid of excess nitrogen. Ammonia, urea, and uric acid are the most common nitrogenous wastes that animals excrete. Protein metabolism generates all of these nitrogenous wastes.
Ammonia is the most toxic of these nitrogenous wastes, and it is the most common but requires the least energy. Urea is more harmful than uric acid, but it is less harmful than ammonia, reducing the amount of energy required to synthesize it. Uric acid is the least harmful, a non-poisonous particle with four nitrogen molecules. This is useful for birds and reptiles that lay hard eggs because it eliminates the most nitrogen, uses the least amount of water, and is not toxic. It also takes the most energy input.
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In the Northern Hemisphere, winter generally begins on December 21 or 22. This is the winter solstice, the day of the year with the shortest period of daylight. Summer begins on June 20 or 21, the summer solstice, which has the most daylight of any day in the year. Spring and fall, or autumn, begin on equinoxes, days that have equal amounts of daylight and darkness. The vernal, or spring, equinox falls on March 20 or 21, and the autumnal equinox is on September 22 or 23.
Answer:
Crocodiles and snakes are more alike since they both develop from an egg.
Lizards and snakes are more alike since both species have a recent common ancestor.
