<span>Chemical bonds hold atoms
together to form compounds. The answer is letter D. Chemical bonds may result
through the sharing of electrons as in covalent bonds or from the electrostatic
force of attraction between atoms with opposite charges as in ionic bond. There
are other bonds that exist to other compounds such as metallic bond and
hydrogen bonding. Also, the type of bonding will help us determine what will be
the phase of the compound. Just like in liquids, attractive forces are caused by
van der Waals bonds.</span>
Best Answer: A satellite in a polar orbit passes over both poles, but the earth rotates beneath it. The time taken for each orbit of the earth depends on the height of thsatellitete. If the satellite is in a circular orbit 260 kilometers above the surface it will have an orbital period of two hours.
Answer:
The following scientists have performed different experiments that were helpful in providing evidence that DNA is the genetic material. The summarize experiments are as follows-
1. Fredrick Griffith- the experiment was an experiment performed in 1928. It was one of the experiments that exhibit that bacteria can acquire through the process of transformation.
2 Oswald Avery, Maclyn McCarty, and Colin MacLeod: this experiment exhibited that DNA can transform the cell properties, and clarifying the chemical properties of the genes.
3. Alfred Hershey and Martha Chase: They determined that even the bacteriophage has a protective coat around it but the DNA that is present inside is the genetic material that has the ability to produce the progeny inside a bacterium.
4. Erwin Chargaff: He proposed tow rules which were named after him as chargaff rules. This tells that natural DNA the number of cytosines is equal to the number of guanine units and adenine to Thymine units.
The difference between pH 3 and pH 4 is a 10 fold difference in the concentration of H+
Rod shaped = bacilli
Purple =Gram positive
The bacteria is Lactobacillus
