Answer:
Correct
Explanation:
The statement is correct because, during the chemical synapses, the transmission of information takes place when the presynaptic neuron releases a <u>neurotransmitter</u> that binds to a specific receptor located in the postsynaptic membrane. The release of these neurotransmitters happens almost always when the action potential reaches the synaptic terminal. In the membrane of the synaptic terminal, the number of Ca++ voltage-depended channels is greater than in other parts of the membrane, hence, when the action potential depolarized the membrane, the channels open and the Ca++ defuses actively into the cell. The intracellular concentration of Ca++ is very high and this strong and rapid increase, facilities the depolarization of the membrane and <u>allows the release of the neurotransmitter to the postsynaptic membrane</u>.
A or the balance between organic matter and mineral matter
Answer:
the us has 63 national parks, which are congressionally-designated protected areas operated by National Park service, an agency of the department of the interior.
Answer:
The correct answer is- Immune system
Explanation:
There are physical, chemical and immunological barriers present in our body which helps us to protect from the foreign antigen. They all assist each other and helps in pathogen removal from our body.
The physical barrier includes skin, gastrointestinal tract, respiratory tract, etc which do not allow the microbe to enter the body. Chemical barriers include tear, saliva, acid in the stomach which kills microbes on the body surface.
Immune cells like macrophages, B cells kills microbes when it gets in the body. Lymphatic system also contain immune cells and helps in microbe removal.
So the immune system is assisted by physical barrier, chemical barrier, and lymphatic system.