Answer:
C.were formed at the same time.
Explanation:
If the same index fossils occurred in two separate rock layers, the two rock layers would probably have been established at the same time. Index fossils aid the characterizing and classify of geologic period.
would be the answer to this question. Behavioral Adaptation means a specific object helps the host body. Which would be C. A cactus needs that water survive.
Answer: The electrons in an atom that take part in chemical bonding are the electrons in the outermost shell and they are called valence electrons.
Explanation: An atom is composed of three particles: protons, neutrons and electrons. The protons and neutrons occupy the centrally located nucleus while the electrons are located in the empty space outside the nucleus. Electrons are distributed around the nucleus in paths called electron shells. The electrons in the outermost electron shells are called the valence electrons. The valence electrons are the electrons that participate in chemical bonding. During chemical bonding, the valence electrons are either transferred from one atom to another or the valence electrons are shared between two atoms. A type of chemical bonding in which there is a complete transfer of valence electrons from an atom of a metal to an atom of a non-metal so that can attain octet or duplet structure of noble gases is called electrovalent or ionic bonding. A type of chemical bonding in which there is sharing of electrons between two atoms of non-metals so that both can attain the octet or duplet structure of noble gases is called covalent bonding.
A neurotransmitter is a chemical substance that is released by a nerve fiber due to the presence of nerve impulses; it transport chemical information from one nerve to the other. A receptor refers to a protein molecule that is found on the cell membranes of every cell, it functions by responding in an appropriate manner to chemical signals that are coming from outside of the cell.
The relationship between the neurotransmitter and the receptor is that the neurotransmitter molecules typically bound with the appropriate receptors and bring about the expected changes in the targeted postsynaptic cell.
