A way to measure plant growth. The issue with an experiment like this, is there is no way of telling if the plant would have grown differently if you had not added the extra fertilizers. To properly test this you must have "control" plants that would grow in the same conditions just without any fertilizer. You have to have multiple plants as subjects to get a good amount of data and then take the averages of each fertilizer and compare them that way.
(Just as a headsup if you are going to do this as a science fair project, don't use raw egg or unprocessed chicken poop. The egg turns the soil into rock and the chicken feces smells horrible and starts to mold. >< )
These characteristics are only present during embryonic development in some chordates. The notochord provides skeletal support, gives the phylum its name, and develops into the vertebral column in vertebrates. The dorsal hollow nerve cord develops into the central nervous system: the brain and spine.
Answer:
Scientists believe that the different types we know emerged as early humans adapted to infectious diseases.
Explanation:
Different human blood types probably emerged to ward off infectious diseases. The incompatibility of some blood types, however, is only an "accident" of evolution. But this is a relatively recent problem, since blood transfusion has been around for only a few hundred years.
There are four main blood types. The oldest is B, which must have originated about 3.5 million years ago - it existed even before the human species evolved from its hominid ancestors, from a genetic mutation that modified one of the sugars in the surface of red blood cells.
Approximately 2.5 million years ago, mutations inactivated sugar, resulting in type O blood, which has neither type A nor B. sugar. AB blood, as it is easy to suppose, is covered by both sugar A and sugar by B.
The talus (astragalus) articulates above with the bones of the lower leg to form the ankle joint. The other six tarsals, tightly bound together by ligaments below the talus,function<span> as a strong weight-bearing platform. The calcaneus, or heel bone, is the largest </span>tarsal<span> and forms the prominence at the back of the foot.</span>
Muscle cramp refers to the sudden contraction of an involuntary muscle. It can be caused by many factors including inadequate presence of some minerals such as calcium in the body; it can also be caused by poor circulation.
Straightening an althelete's leg and rubbing it vigorously make the muscle to relax and to snap back in place.
