<u>Answer:</u>
<em>A constant is something whose value cannot be changed and is used for comparison purpose. </em>
<u>Explanation:</u>
The controlled variable is a type of variable whose value is kept constant during the experiment to get the desired or expected result. The difference between constant and a control variable is that the constant can never be changed.
However, the value of control variable can be changed but is kept constant with a purpose in an experiment to get the data. The controlled variable in a battery can be the multi meter that should be used for all the batteries.
Answer:
D. A segment of DNA molecule
Explanation:
Gene is a segment of a DNA molecule that holds instruction needed for the synthesis of useful products (protein). Ideally, DNA is the storage material of genetic information in a cell. The DNA harbors the GENE, which itself is being expressed in order to use the information contained in it to produce useful products responsible for the phenotype of an organism.
A gene contains sequences made up of nucleotide bases that determines the sequence of amino acids to be produced, and ultimately the type of protein.
Answer:
Oligodendrocytes in the brain and spinal cord and Schwann cells in the peripheral nervous system are specialized types of glia that build the myelin sheaths that surround neurons.
Explanation:
Myelin sheath is an insulating layer, which covers neurons. It is made up of protein and fatty substances. This myelin sheath permits electrical impulses to move very fast along the neurons.