<span>Physical fitness is something that constantly needs to be worked on to maintain or improve it. Thus, it has a continuous nature. Think of running a mile. If you train for weeks, you can achieve a faster time. Once you attain the goal mile time that you want, you still have to keep training to further maintain it. However, if you stop running, the time it takes to run a mile will increase, and your physical fitness will decrease. This shows the concept of physical fitness as continuous, because to maintain or improve it, you must continue training.</span>
Axons are long nerve processes which carry nerve impulses from the Soma to other neurons, they vary in length but can become almost as long as half of the human body.
The soma (body) of the neuron contains the nucleus which acts as the cell's control centre, these contain many small neurofibrils which project from the nucleus into the dendrites.
Dendrites are short, thick processes which branch out of the soma in a tree like manor. They conduct nerve impulses to the soma.
The three categories of neurons:
Afferent (Sensory) Neurons have the dendrites connected to receptors such as the eyes, ears etc. These receptors change the information they receive into electrical impulses that are transmitted to other neurons. In sensory neurons the axons are connected to other neurons.
Efferent (Motor) Neurons have the dendrites connected to other neurons, the axons are connected to effectors. Effectors are either glands or a muscle cell that is the receiving end of the nerve impulse. The nerve, when excited will cause the effector to react (move, contract, or secrete etc).
Internuncial Neurons have both the dendrites and the axons are connected to other neurons. They are sometimes referred to as connector neurons.
Internuncial neurons are found throughout the body, but especially in the spinal cord and brain.
Properties and characteristics of Neurons:
Normally the electrical impulses (messages) travel through a neuron in only one direction.
The axon may be surrounded by a 'coat' of lipids (fats) and proteins known as the myelin sheath which acts as an insulator.
Neurons are specialist cells that have lost the ability to reproduce themselves. Once the soma of a neuron has died the entire neuron dies, and can never be replaced.
Repair of damaged neurons only occurs in myelinated neurons.
white matter are coloured by myelin, consisting of many neurons supported by neuroglia.
grey matter is soma and dendrites or bundles of unmyelinated axons and neuralgia.
Answer:
Agonist muscles and antagonist muscles refer to muscles that cause or inhibit a movement.
Explanation:
Agonist muscles cause a movement to occur through their own activation.[4] For example, the triceps brachii contracts, producing a shortening contraction, during the up phase of a push-up (elbow extension). During the down phase of a push-up, the same triceps brachii actively controls elbow flexion while producing a lengthening contraction. It is still the agonist, because while resisting gravity during relaxing, the triceps brachii continues to be the prime mover, or controller, of the joint action. Agonists are also interchangeably referred to as "prime movers," since they are the muscles considered primarily responsible for generating or controlling a specific movement.
The Answer is A: Someone who has the capability to guide others!
I say c. cause it is show casing more then one
