The electrons in the outermost shell of the covalent compounds are shared by nearby atoms. As there are no free electrons for conducting electricity, the covalent compounds are perfect insulators at absolute zero. As the temperature increases, some electrons move from valence band to conduction band. This gives rise to conductivity. But as the numbers of charge carriers are very low, covalent compounds are poor conductors. On the other hand metals are good conductors cause of their bonding. Metallic bonding consists of a sea of electrons rather than discreet bonds. The free electrons are able to move freely. Since electricity and heat need electrons to move, the bonding promotes conductivity.
Answer:
C.
Explanation:
Absolute dating is defined as the method used to determine the age of biotic or abiotic things on a specified chronology in geology and archaeology.
Layers of the soil are used to determine the age of a geologic event is not a form of absolute dating because the deepest river deposits in the specific basin is used to determine the geological event.
So, the deposits of soil are used to tell the the age of a geologic event and not the layers of soil.
Hence, the correct option is C.
Membrane is the answer i think
Answer:
(a) Gg × Gg; (b) genotypic = 1:2:1, phenotypic = 3:1
Explanation:
a) A cross between two gray seeded plants produces progeny with gray and white seeds in 3:1 ratio (302:98=3:1). This means that the parent plants are heterozygous and each has at least one recessive allele. If the allele "G" is responsible for gray seed and the allele "g" imparts white color to the seeds, the genotype of the heterozygous parents would be "Gg".
b) A cross between two heterozygous gray seeded parents would produce progeny in following ratio:
Genotype ratio= 1 GG: 2 Gg: 1 gg
Phenotype ratio= 3 Gray: 1 white
<span>radio waves, microwaves, gamma rays, X-rays, visible rays
Hope this helps</span>
