Answer:
The pain nerves in her hand go to the brain to notify it. The brain processes this information and decides to tell the hand to remove itself from the stove. Then, the brain sends this signal back to the hand to make it remove tself from the stove.
Explanation:
When the blood plasma becomes less concentrated and the level of ADH decreases, aquaporins are removed from collecting tubule cell membranes, and the passage of water out of urine and into the blood decreases.
Answer: The diffusion of ions along the axoplasm is faster,in myelinated compare to unmyelinated,
Neurons are the structural and functioning units of nervous system.They are the vehicles for transmission of impulses as electrical signals from one part of the cells,and from one part of the body to another.
The basic structural components of a typical neuron are the cellbody, the axon, and the dendrites.
Based on structure neurons are classified as myelinated and unmyelinated.This is based on the the surrounding layer of myelin sheath around the axon. The myelin provides the insulating layer for the axon.And ensures fast movement of impluses.
In myelinated neurons the myelin sheath are interrupted at intervals by gaps along the length of the axon called Nodes of Ranvier. These gaps contains more Na-K channels for influx and out-flux of K and Na+ ions for transmission of impulses.
The cytoplasm of axon is called axoplasm,Since this is surrounded by myelin sheath which contains Na-K+ channels,The rate of diffusion of ions along these channels is faster for depolarization to take place than in unmyelinated neurons. Inaddtion as these ions diffusion increases,its jump faster at the nodes of Ranvier (saltatory conduction) to the next axoplasm which further speed up the rate of transmission.
Unmyeinated lacks myelin sheath,therefore the exchange and the rate of diffusion of ions along the axons is low.
Explnation:
No animals don't need light
Answer:
Cell membranes are selectively permeable which means it allow certain molecules to move across it into and out of the cell. Cells need to be able to transport these substances to live and grow.
Transport of ions, water maintains the osmotic pressure of the cell. Transport of sugars like glucose is necessary to generate energy for the metabolic activities of the cell. Gases like CO2 are waste products of metabolic reaction which are removed by the cell through the cell membrane. Amino acids are required to make proteins.
Transport across cell can occur through active and passive transport and transport of these substance are necessary for a cell to live and function properly.
