Components of CNS and PNS, Function of ANS, Sensory and Motor Neurons, Reflex Action, All-or-None Rule, Synaptic Inhibition

Running head: BIOLOGY
BIOLOGY
Name of the student:
Name of the university:
Author note:

BIOLOGY1
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Activity 2.......................................................................................2
Activity 3.......................................................................................3
Activity 4.......................................................................................4
Activity 5.......................................................................................5
Activity 6.......................................................................................6
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Activity 9.......................................................................................7
Activity 10......................................................................................8

BIOLOGY2
Activity 1
List the components of the CNS and the PNS.
The central nervous system CNS consist of two chief components; the spinal cord
which serves as a channel for the signals with in the brain and the other parts of the body. It
functions by controlling the modest musculoskeletal reflexes deprived of the input received
from the brain. The second is the brain whose function is to integrate the sensory information
and synchronizing the function of the body. There are other parts of the brain which functions
by regulating the homeostasis and the ability to feel and think (Louveau et al. 2015).
The peripheral nervous system PNS of a human being comprises of two parts; the
somatic nervous system consisting of 12 sets of the cranial nerves functioning for the head
and the posterior of the neck, and the autonomic nervous system which consists of 31 pairs of
the spinal nerves of the body (Delp et al. 2015).
Activity 2
What is the function of the ANS?
The autonomic nervous system (ANS) functions by maintaining the body’s blood
pressure, normalizes the breathing or the respiratory rate. It also has a function of influencing
the urination, digestion and modifies the sexual stimulation. The sympathetic part of the
autonomic nervous system supervises the reactions which includes the response to stress and
also the response towards any threat or injury and also helps the body to restore after the
threat has passed. The autonomic nervous system’s parasympathetic part function is to
control reactions which are associated with ingestion, development, and reproduction (Glick,
Glick and Stein 2019).
Activity 3

BIOLOGY3
(i) What is a sensory neuron
The sensory neurons comprise the five major senses which includes the smell, sight,
taste, hearing and touch. The sensory neuron permits the ability to smell, taste, see, hear and
feel anything. These neurons carry the signals from the periphery or the sense organs to the
brain or the spinal cord (Williams et al. 2016).
(ii) What is a motor neuron
The motor neuron is that neuron which passes from a ganglion or the central nervous
system in the
direction
of the muscles
and generates
an impulse
which leads to
the
movement of the body parts (Radunovic et al. 2017).
Explain what is happening in the diagram below for the thumb to move.