063 The Divisions of the Nervous System

Summary

In episode 63 of Interactive Biology TV, host Leslie Samuel explores the divisions of the nervous system. She explains the central nervous system, which includes the brain and spinal cord, and its role as the body's processing center. The peripheral nervous system, which connects to limbs and organs, is further divided into the somatic nervous system (controlling voluntary activities) and the autonomic nervous system (regulating involuntary functions). The autonomic nervous system is split into the sympathetic (fight or flight) and parasympathetic (rest and digest) branches, providing a comprehensive overview of the body's control mechanisms.

Takeaways

• 🧠 The nervous system is the control center of the body, consisting of the central and peripheral nervous systems.
• 🏢 The central nervous system includes the brain and the spinal cord, serving as the processing center for the body.
• 🧠 The brain is the central hub of the nervous system, responsible for thought, emotion, and coordination of bodily activities.
• 📡 The spinal cord acts as a communication link between the brain and the rest of the body, transmitting sensory and motor signals.
• 🔗 The peripheral nervous system connects the central nervous system to the limbs and organs, facilitating communication.
• 🏋️‍♂️ The somatic nervous system controls voluntary activities, such as walking and smiling, involving the skeletal muscles.
• 🫀 The autonomic nervous system manages involuntary bodily functions like heart rate, respiration, and digestion.
• 🚨 The sympathetic nervous system is associated with the 'fight or flight' response, activating during stress.
• 🛌 The parasympathetic nervous system is responsible for 'rest and digest' activities, promoting relaxation and recovery.
• 🔄 Both the sympathetic and parasympathetic systems are part of the autonomic nervous system, balancing each other's effects.

Q & A

What are the two main divisions of the nervous system?

The two main divisions of the nervous system are the central nervous system (CNS) and the peripheral nervous system (PNS).

What is the central nervous system and what are its primary components?

The central nervous system is the processing center of the nervous system, consisting mainly of the brain and the spinal cord.

What role does the brain play in the nervous system?

The brain is the center of the nervous system where most of the processing occurs, including thought, emotion, and coordination of the body's activities.

What is the function of the spinal cord in the nervous system?

The spinal cord sends signals to and from the brain to the rest of the body, connecting the brain to the rest of the body and facilitating sensory and motor signals.

How is the peripheral nervous system divided and what are its two parts?

The peripheral nervous system is divided into the somatic nervous system and the autonomic nervous system.

What are voluntary activities and how are they related to the somatic nervous system?

Voluntary activities are actions that we consciously control, such as walking or smiling, and they are regulated by the somatic nervous system, which involves skeletal muscles.

What is the autonomic nervous system and what are its functions?

The autonomic nervous system controls involuntary bodily functions such as heart rate, respiration rate, and digestion.

How is the autonomic nervous system further divided and what are the two parts?

The autonomic nervous system is further divided into the sympathetic nervous system and the parasympathetic nervous system.

What is the role of the sympathetic nervous system in the body's response to stress?

The sympathetic nervous system is involved in the fight or flight response, increasing heart rate and respiration rate when the body is under stress.

What does the parasympathetic nervous system do and when is it most active?

The parasympathetic nervous system is active during rest and digest activities, promoting relaxation and slowing down bodily functions when the body is at rest and not under stress.

How does the nervous system coordinate the body's activities?

The nervous system coordinates the body's activities through the integration of signals from the central nervous system (brain and spinal cord) and the peripheral nervous system (somatic and autonomic nervous systems).

Outlines

00:00

🧠 Introduction to the Nervous System

In this episode of Interactive Biology TV, host Leslie Samuel introduces the topic of the nervous system's divisions. The nervous system is described as the body's control center, with two main divisions: the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS, which includes the brain and spinal cord, is the processing center where thoughts, emotions, and coordination of body activities occur. The PNS connects the CNS to the limbs and organs, facilitating the transmission of sensory and motor signals.

Keywords

💡Nervous System

The nervous system is the body's control center responsible for receiving, interpreting, and responding to information from the internal and external environment. In the video, it is the main focus, with the host discussing its various divisions and functions, emphasizing its role in coordinating the body's activities.

💡Central Nervous System (CNS)

The central nervous system, which includes the brain and spinal cord, is the processing center of the nervous system. It is responsible for higher cognitive functions and is the part of the nervous system that performs most of the processing. The video explains that the CNS is where 'a lot of processing happens' and is integral to thought, emotion, and coordinating body activities.

💡Peripheral Nervous System (PNS)

The peripheral nervous system connects the central nervous system to the limbs and organs. It is responsible for transmitting sensory signals to the CNS and motor signals from the CNS to the rest of the body. The video describes it as the system that 'connects the central nervous system to the limbs and organs'.

💡Somatic Nervous System

The somatic nervous system controls voluntary activities and is associated with the skeletal muscles. It allows for conscious control over movements such as walking or smiling, which are examples given in the video. The host mentions that this system is responsible for 'control of voluntary activities'.

💡Autonomic Nervous System

The autonomic nervous system controls involuntary bodily functions such as heart rate, respiration, digestion, and other visceral functions. It is not under conscious control and operates automatically. The video describes it as the system that controls 'involuntary things that happen in the body'.

💡Sympathetic Nervous System

The sympathetic nervous system is part of the autonomic nervous system and is involved in the 'fight or flight' response. It prepares the body to react to stress by increasing heart rate and respiration rate, among other things. The video gives the example of a person's body response when going for a jog.

💡Parasympathetic Nervous System

The parasympathetic nervous system is the counterpart to the sympathetic system and is involved in 'rest and digest' activities. It helps the body to conserve energy and restore balance after periods of stress. The video explains that it is active during rest and is responsible for slowing things down and promoting relaxation.

💡Voluntary Activities

Voluntary activities are those that are consciously controlled, such as walking or smiling. The video discusses how these activities are under the control of the somatic nervous system, which allows for direct control over skeletal muscles to perform these tasks.

💡Involuntary Activities

Involuntary activities are those that occur without conscious thought, such as heart rate regulation and digestion. The video explains that these functions are controlled by the autonomic nervous system, specifically highlighting that they 'just happen' without the need for conscious thought.

💡Fight or Flight Response

The fight or flight response is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. The sympathetic nervous system is activated, leading to increased heart rate and respiration to prepare the body for action. The video uses jogging as an example of a situation where this response might be triggered.

💡Rest and Digest

Rest and digest is a state of bodily activity that occurs when the body is at rest and focusing on digestion and other maintenance functions. The parasympathetic nervous system is active during this state, promoting relaxation and recovery. The video contrasts this with the fight or flight response to illustrate the body's different modes of operation.

Highlights

Introduction to the divisions of the nervous system in episode 63 of Interactive Biology TV.

The nervous system is the control center of the body.

Division of the nervous system into the central and peripheral nervous systems.

The central nervous system is the processing center, including the brain and spinal cord.

The brain is the center of the nervous system, responsible for thought, emotion, and coordinating body activities.

The spinal cord's role in sending signals to and from the brain and the rest of the body.

The peripheral nervous system connects the central nervous system to the limbs and organs.

Division of the peripheral nervous system into the somatic and autonomic nervous systems.

The somatic nervous system controls voluntary activities and involves skeletal muscles.

Example of voluntary activity: Contracting leg muscles to walk.

It takes fewer muscles to smile than to frown, highlighting the somatic nervous system's role in facial expressions.

The autonomic nervous system controls involuntary bodily functions.

The autonomic nervous system is responsible for visceral functions like heart rate and digestion.

Division of the autonomic nervous system into the sympathetic and parasympathetic nervous systems.

The sympathetic nervous system is involved in the fight or flight response during stress.

The parasympathetic nervous system is active during rest and digest activities, promoting relaxation.

Summary of the divisions of the nervous system and their functions.

Transcripts

hello and welcome to another episode of

interactive biology TV where we're

making biology fun my name is lesie

Samuel and in this episode episode 63

we're going to take a step back and

we're going to talk about the divisions

of the nervous system so let's get right

into it now if you go all the way back

to episode number one we spoke about the

nervous system and we said that the

nervous system is basically the control

center of the body body and what we're

going to do is we're going to take this

and we're going to look at the different

divisions within the nervous system

first we have the central nervous system

and we have the peripheral nervous

system so these are the two systems that

we can divide the nervous system into

now the central nervous system that is

the processing center of the nervous

system a lot of processing happens here

and the peripheral nervous system is

what connects the central nervous system

to the limbs and the organs so we have

the processing in the Central and then

we have the peripheral nervous system

and these work together very well now

let's take the central nervous system

and divide that that can be divided into

the brain and the spinal cord now the

brain that's the center of the nervous

system uh this is where most of the

processing is happening this is the part

that's found within the skull and this

is where things like thought and emotion

um coordinating the body's activities

all of that stuff happens in the brain

and then of course we have the spinal

cord and the spinal cord sends signals

to and from the brain to and from the

rest of the body so it's connecting the

brain to the rest of the body basically

sensory signals come into the spinal

cord and motor signals go out from the

spinal cord and we're going to talk

about those

as we deal with the peripheral nervous

system so let's head on over there right

now the peripheral nervous system

consists once again of two parts that's

the somatic nervous system and the

autonomic nervous system let's talk

about the somatic first the somatic

nervous system is where we're going to

get control of voluntary activities and

this is where skeletal muscles are

involved so if for example I want to

walk I need to contract the muscles in

my legs and that is a voluntary activity

that is controlled by the somatic

nervous system if I want to smile I need

to control the muscles in my face by the

way it takes less muscles to smile than

to frown but I'm sure you know that um

so this is all in the somatic nervous

system and then of course we have the

autonomic nervous system which is not

voluntary this is the involuntary things

that happen in the body um so it

controls visceral functions like heart

rate respiration rate digestion those

things you don't need to think about

they just happen they are involuntary

and that is under the control of the

autonomic nervous

system now we can take the autonomic

nervous system and of course we can

divide that into two parts we have the

sympathetic nervous system and the

parasympathetic nervous system now the

sympathetic nervous system that is

involved in the fight or flight response

so it's what happens to your body when

your body is under stress things like

increasing your heart rate and

respiration rate anything that you're

increasing this is usually under the

control of the sympathetic nervous

system so if you go for a nice long jog

and your heart rate starts increasing

and your respiration rate increases that

is under the control of the sympathetic

nervous system and then of course we

have the parasympathetic which is

opposite to the sympathetic and this is

involved during rest and digest

activities so it's the opposite of under

stress it's when there's rest you're

slowing things down you're relaxing that

is more

parasympathetic and these are both under

the autonomic nervous system so there we

have it those are the divisions of the

nervous system I hope that was clear to

you that's pretty much all I want to

cover in this video as usual I want to

invite you to visit the website you know

it it's at interactive-compensatory