Answer:
False
Explanation:
Even though the idea is logical, Earth's seasons are actually caused by the tilt of earth,earth rotating on it's axis, and Earth's revolution around the sun
hope this helps!
Answer: The postsynaptic cells has many synapses with many presynaptic neuron.
Synapse can be defined as a structure that
allow neuron to send a chemical or electrical signal to another neuron.
However, postsynaptic potential is a temporary change in the electrical
polarization of the membrane of a nerve cell and they are known to be receiver
of neurotransmitter message.
Black the creamer makes it look white along with the side of the cup that it is in and the lighting and your phones picture could also make it different than it looks
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:
Answer and explanation:
Epinephrine and norepinephrine are two hormones that are released from the adrenal medulla when the body is under stress (like during exercise, for example) as a part of the sympathetic response.
These hormones have many functions and they all work together to prepare the individual for a fight or flight response -<em> like increasing heart rate and producing bronchodilatation</em>. One of these functions is the rise of glucose levels in blood which is important for this substance to reach several tissues, like the skeletal muscle. The skeletal muscle will make use of this glucose to produce ATP and generate the required energy for muscle contraction through a process called glycolysis, which is key for the fight or flight response mentioned above.
When we exercise, glucose levels rise thanks to these hormones so the skeletal muscle can have enough energy to contract and move as we want. If the exercise is too intense or prolongued, glucose levels will drop and other fuels will be needed to sustain this activity, like stored glycogen and fat.
