Answer:
An index fossil is also known as guide fossils or indicator fossil. They are fossils used to determine and identify geologic periods.
The main characteristics of an index fossil include :
1.It must be distinctive.
2.It must be widespread.
3. It must be abundant
4. It must be limited in geologic time.
Due to trends and studies of most fossil-bearing rocks being formed in the ocean, the major index fossils are mostly marine animal or plant organisms.
Answer:A) The ocean is hypertonic to the erythrocytes.
Explanation:cells shrink when placed in an hypertonic solution.
This shrinkage occurs does to the movement of water out of the cell and through the cell membrane.this phenomenon is called plasmolysis.
The movement of water out of this cell occurs through osmosis.osmosis is the movement of water from a region of high concentration of solute to a region of low concentration of solute, through a semi-permeable membrane.
In this case,sea water has a higher concentration of solute (hypertonic) and the blood cells has a lower concentration(hypotonic) .the cell membrane serves as the semi-permeable membrane and and a result water moves out of the cell
The covalent compound for cci4 is carbon tetrachloride
Answer:
Genes get exchanges through the parent genes
hope this help :)
I believe the answer is C.