Which of the following statements about myelin is not true? All axons have a myelin sheath. The myelin sheath is a factor in multiple sclerosis. Under a microscope, myelin is white in color. The myelin sheath affects the speed of neural transmission.

Option A is false.

All axon have myelin sheath.

Explanation:

Myelin sheath is a layer that surrond the nerve cells axon and provide insulation to the nerves. Myelin sheath are made up of protein and lipids.

Axon is a long projection of nerve cell that conduct electrical impulses away from the cell body. Not all axons are have myelin sheath

Axon can either be myelinated i.e is covered with Myelin sheath or unmyelinated. The myelinated axons are ensheathed along their length. The presence of myelin sheath on axons help to increase in speed of electrical impulses spreading all ng the myelinated fibre. Oligodendrocytes of Central nervous system and schawn cells of peripheral nervous system perform the function of producing myelin sheaths.

Examples of nerves without myelin sheath is the axons of group c nerve fibre.

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.