To perform this test to check if gold is real, make a light, tiny scratch on the item using a small nail file. Choose a spot that is not noticeable if possible. Use a dropper to apply a small drop of nitric acid to the scratch. If there is no reaction, then the piece is probably made from real gold.
Answer:
1. coevolution
2. abiogenesis
3. Endosymbiont Theory
4. It's estimated that over 99 percent of the species that have existed on Earth at some point in time are extinct today.
5. Coevolution implies that the evolution of one species is dependent on and works in relation to the evolution of another species. This may cause positive or negative impacts and could be beneficial to both organisms or only to one.
6. This theory states that the first building block of life that allowed for reproduction of organisms was the development of self-replicating RNA. This hasn't been able to be fully demonstrated in any science experiment but is based on the idea that there are RNAs that can catalyze biochemical reactions on their own without proteins.
7. This process points to the development of structures through the envelopment of smaller cells that perform specific functions. This is how eukaryotic cells evolved from prokaryotic cells.
8. This experiment was important because it showed that, in the right primordial soup, organic compounds could develop from inorganic compounds.
Explanation:
penn foster
Have cones as reproductive structures.
Have vascular tissue.
Answer:
D: Black hole
Explanation:
The formation and life cycle of stars
A nebula. A star forms from massive clouds of dust and gas in space, also known as a nebula. ...
Protostar. As the mass falls together it gets hot. ...
Main sequence star. ...
Red giant star. ...
White dwarf. ...
Supernova. ...
A neutron star or black hole.
