Unit 5: Interaction: The Nervous and Endocrine Systems

INDEX1. The interaction process2. The neuron and electric

signals3. The nervous system4. The endocrine system5. Healthy habits: diseases of the nervous and endocrine

systems

A. To adapt the body to changing conditions, in the internal as well the external environment.

E. To connect and coordinate the different parts of our body so thatthey work together.

C. Nervous and endocrine systems are in charge of interaction process.D. Respiratory and reproductive systems are the main systems involved ininteraction.

B. To digest food and to absorb nutrients .

Decide which the following sentences are related to the interaction process

1. The Interaction Process

To adapt the body to changing conditions

To connect and coordinate the different parts of our body

1.1 Functions of the interaction processes

To take part in homeostasisHomeostatic processes maintain the body’s stability.

1.2 Systems that participate in the interactionprocess

Stimuli are detected by the Sensory Organs.

The information is transmited and a response is created by theNervous System.

The response is transmitted to the effector organs: -Locomotor system movement-Endocrine system hormones

Activities 4, 5 and 6 page 7

Videos 3C: NervousSystemStimuliGeneralNervousSystem

. Answer the following questions:•What are the organs which receive the information of the environment?•What are the systems which analyse the information and make a response?•What are the organs which execute the response?•What is a nervous impulse?•What are neurotransmitters?•What is the difference between sensory neurons and motor neurons?•What are the two main parts of the Central Nervous System?•What are the three protections of the CNS?•What is the difference between craneal and spinal nerves?•What are the integration centres in the reflex act and in the voluntary act?

https://www.youtube.com/watch?v=p5zFgT4aofA neurotransmittershttps://www.youtube.com/watch?v=mItV4rC57kM synapses

Label

2. The neuron and electric signals

Direction of the nerve impulse

The nervous system’s anatomical and physiological unit is the neuron.•Schwann cells: they isolate the axon, so that the nerve impulse is transmitted faster. They are made up of myelin.

Types of neurons depending on their function

Sensory neurons

They transmit information from the receptors to

the nerve centres

Motor neurons

They transmit the signals from

the nerve centres to the effector organs

Interneurons

They connect them (located in the brain and in the spinal cord)

Neurons transmit nerve impulses (electric signals) from the dendrites to the axon.

Synapses are connections between neurons. There is not physical contact between neurons. The gap between them is called synaptic cleft.

Neurotransmitters are chemical substances released by the axon of a neuron when it is reached by a nervous impulse. These substances are detected by the following neuron which produces another nervous impulse.

https://www.youtube.com/watch?v=p5zFgT4aofA neurotransmittershttps://www.youtube.com/watch?v=mItV4rC57kM Chemical Synapse Animation

One of the most important features of chemical synapses is that they are the siteof action for many drugs. Synapses are affected by drugs such as cocaine, morphine, alcohol, LSD, and countless others. These drugs have different effects on synaptic function.

3. The Nervous System

Components of the Nervous System

Central Nervous System (CNS)

Brain (encéfalo)

Cerebrum (cerebro)

Cerebellum

Brain stem (bulbo

raquídeo)

Spinal cord (médula espinal)

Peripheral Nervous System (PNS)

Somatic nervous system

Autonomic nervous system

Sympathetic nervous system

Parasympathetic nervous

system

3.1 The Central Nervous System (CNS)It is responsible for integrating information received, coordinating it and preparing a response. It has two parts:• the brain• the spinal cord

Protections of the CNS

Bone skull

spine/ vertebral

column/backbone3

membranes called meninges

Dura

Arachnoid

Pia materA liquid called cerebrospinal fluid (líquido

cefalorraquídeo)

Types of tissue in the

CNS

Grey matter

Cell bodies and

dendritesWhite matter

Axons (with

myelin)

3.1.1. The spinal cord

The Grey matter is found in the centre and it is shaped like a butterfly’s wings.

The white matter is in the outer area.

Central canal: Channel which contains cerebrospinal fluid.

Functions of the spinal

cord

Reflex actions

Pathway for messages from/to the

brain from/to the rest of the

body

Reflex action

Spinal cord injuries

3.1.2. The brain Main parts of

the brain

Brain stem Cerebellum Cerebrum

A.pituitary gland / pineal gland

B.cerebrumC.skull D.corpus callosumE. thalamus F. hypothalamus G.brain stem H.cerebellum I. meningesJ. spinal cordI

It controls the heartbeat, breathing, blood pressure, etc. It also regulates sleep.

Brain stem

It intervenes in the control of muscles, balance and the posture of the body.

Cerebellum

CerebrumIt analyses all the information from the receptors and orders voluntary responses.

It is the centre for language, thought, creativity learning and memory. It is the only conscious structure of the encephalon.

The grey matter forms the cerebral cortex, which is responsible for acquired behaviour.

HW: Activities 10, 12, 15

It is made up of nerves. A nerve contains a mixture of nerve fibres (axons)

Nerves can be:- Craneal linked to the brain- Spinal linked to the spinal cord

3.2 The Peripheral Nervous System: the nerves

3.2.1. The somatic nervous system

It receives information from external stimuli .It transmits signals for voluntary muscle contractions.

3.2.2. The autonomic nervous system

It controls involuntary body functions.It is linked to the:• Grey matter of the spinal cord• Brain stem• Hypothalamus

Parts of the autonomic

nervous system

Sympathetic nervous system

It makes the organs work

more effectively

Parasympathetic nervous system

It provokes relaxation and

the organs work more slowly

Alzheimer and Parkinsonare degenerative illnesses in which neurons are destroyed.

Alzheimer’s diseaseproduces a progressive loss of memory and ability to reason.

5. Diseases Related to the Nervous System

Parkinson affects movement and causes trembling and rigidity.

Meningitis is an inflammation of the meninges due to a viral or bacterial infection.