Answer: A. Brain - Organ level
B. Neurons - Cellular level
C. Neurotransmitters - Chemical level
D. Neurons and neuroglial cells - Tissue level
E.Brain combined with the spinal cord and spinal nerves - Organ System level
Explanation: There are five levels of organisation of life; cell, tissue, organ, system and organism.
The smallest unit is cell. Neurons are nerve cells.
Aggregation of cells forms a tissue. Neurons and neuroglial cells aggregate to form nervous tissues and are hence at tissue level.
Aggregation of tissues forms an organ. Brain is an example of organ. It is formed from aggregation of nervous tissues.
Tissues aggregate to form organs while aggregation of organs constitute a system. The nervous system consist of brain combined with spinal cord and spinal nerves.
The nervous system release chemicals called neurotransmitters.
Answer:
A or E
Explanation:
Check for either the dorsalis pedis pulse(on top of the foot) or the posterior tibial pulse(located behind the ankle bone).
<span>bacteria that require a constant supply of oxygen in order to survive are called
</span><span>Obligate aerobes
</span>because these need oxygen to grow and for their all necessary processes
The option B cannot be correct because they dont need oxygen while C are those that can also live without oxygen
so option A is correct
hope it helps
Replication starts at the ORIGIN OF REPLICATION.
In prokaryotes which has close double stranded DNA molecule, replication usually starts from a single origin of replication and it proceeds around the circle bidirectionally, that is, in both directions. The process of replication in prokaryotes is very rapid and it produces only a few errors.<span />
