Transcript File

Higher Human Biology
Unit 3
Neurobiology & Communication
KEY AREA 1: Divisions of the Nervous System & parts of the brain
Reminder from N5 Biology!
Discuss these questions with a study buddy or your group
1.
2.
3.
4.
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12.
What is the nervous system?
What is the CNS?
What are the 3 main parts of the brain?
What is a reflex action?
What makes up the reflex arc?
What is a synapse?
What is the Endocrine System?
What are Hormones?
Where do Hormones have an effect?
What is Homeostasis?
Why is it important that our Glucose, Water & Body Temperature are
controlled?
Which parts of our brain help to control blood water concentration
and temperature?
Higher Human Biology
We are going to build on the knowledge and skills that you developed during N5 and will
learn about the following Neurobiology key areas : -
Key Area 1 - Divisions of the nervous system & parts of the brain
Key Area 2 - Perception and memory
Key Area 3 - The cells of the nervous system and neurotransmitters at synapses
Key Area 4 - Communication and social behaviour
Neurobiology & Communication Learning Intentions
KEY AREA 1 - Divisions of the nervous system & parts of the brain
a) Structure & function of the Central Nervous System (CNS)
b) Structure & function of the Peripheral Nervous System (PNS) and the Somatic
Nervous System (SNS)
c) Functions of the medulla and cerebellum in the central core of the brain
d) Functions of the limbic system
e) Functions of the cerebral cortex in receiving information, coordinating
voluntary movement and making decisions in light of experience
f) Localisation of brain functions including sensory and motor areas and association
areas
1a) Structure & function- Central Nervous System (CNS)
The nervous system is made up of the:Brain
Spinal Cord
Nerves Sense Organs
Structural division of the nervous system: Central Nervous System
(CNS)
(Brain & Spinal cord)
Peripheral Nervous System (PNS)
(Nerves)
Peripheral nerves contain a sensory pathway made of sensory
nerves and a motor pathway made of motor nerves
Sensory pathways carry nerve impulses from receptors
(e.g. skin) to the CNS
The brain analyses the information and sends nerve impulses
along motor pathways to effectors (e.g. muscles) which then
bring about a response e.g. muscle contraction
1b) Structure & function-Central Nervous System (CNS)
CNS
Nerve impulses carried by
sensory neurons in sensory
pathways
receptors
stimuli
Nerve impulses carried by
motor neurons in motor
pathways
effectors
responses
1c) Peripheral Nervous System(PNS) & SomaticNervous System(SNS)
Somatic Nervous System (SNS) contains sensory and
motor neurons which control the voluntary movement of
skeletal muscles
SNS brings about some involuntary actions (e.g. reflex
response) but majority of actions are under voluntary
control (e.g. picking 4 favourite chocolates out a large box
of chocolates)
Autonomic Nervous System (ANS) regulates the internal
environment by controlling structures and organs (e.g.
heart, blood vessels, bronchioles) This control is
involuntary because it works automatically without the
person’s conscious control being involved
The sympathetic and parasympathetic systems of the
ANS are antagonistic, meaning that they affect many of
the same structures but in opposite ways in order to
maintain a stable internal environment
1d) Peripheral Nervous System(PNS) & Somatic Nervous System(SNS)
Divisions of the Nervous System
Structural & Location Division
Functional Division
1e) Peripheral Nervous System(PNS) & Somatic Nervous System(SNS)
Antagonistic Methods of the Sympathetic and Parasympathetic System in
response to a man chasing you!
Sympathetic System
Parasympathetic System
Type of response
“fight or flight”
“rest and digest”
Response occurs
At start of event when sensory
nerves stimulated
At end of event when excitement is
over
Heart Rate
Increases
Return to normal
Blood Pressure
Increases
Return to normal
Blood supply
Increased supply at muscles
Decreased supply at gut/skin
Return to normal
Peristalsis increases
Nervous perspiration
Increases
Return to normal
Characteristics
Thudding heart
White face with fear
Clammy armpits and hands
Return to normal
Adrenaline(epinephrine) Produced
Not produced
Response
Return to normal to help body
conserve resources and store energy
Fight or run away!
1f) Autonomic Nervous System - antagonistic nature
1g) Peripheral Nervous System(PNS) & Somatic Nervous System(SNS)
Sympathetic & Parasympathetic balance each other – body rarely at
extremes
1h) Fight or Flight
 ‘Fight or flight’ – sympathetic
nervous system sends more
impulses than the parasympathetic
in order to prepare the body to
use energy quickly
 Heart rate and blood pressure
increase and blood supply diverted
to skeletal muscles
 Nervous perspiration increases
 Epinephrine production stimulated
 After the ‘fight or flight’ situation
has passed the parasympathetic
nervous system takes over briefly
to calm you down
1i) Rest and digest
 After the ‘fight or
flight’ situation has
passed the
parasympathetic nervous
system takes over
briefly to calm you down
 Heart rate and blood
pressure drop
 Rate of peristaltic
contractions increase
 Blood re-diverted back
to intestines
1j) The Brain
The brain is composed of 3 interconnected layers : The central core
- Medulla(breathing, heart rate ) &Cerebellum (balance, coordination, posture)
The limbic system
- Hypothalamus
The cerebral cortex
- Outer layer of the cerebrum
1k) Functions of the Limbic System
The limbic system is found in the cerebral
cortex
The function of the limbic system is to:Process information to form long-term
memories
Regulate emotions (e.g. anxiety, fear,
aggression)
Influence biological motivation (e.g. hunger,
thirst, sex drive)
The limbic system contains the hypothalamus
The hypothalamus is connected to the
pituitary gland, and acts as a link between the
nervous system and the hormonal (endocrine)
system
1l) Functions of the Cerebral Cortex
The cerebral cortex is the centre of
conscious thought; it also recalls memories
and alters behaviour in light of experience
The cerebral cortex is the outer layer of
the cerebrum and is split into two halves
called the cerebral hemispheres.
The left hemisphere processes information
from the right visual field and controls the
right side of the body
The right hemisphere processes
information from the left visual field and
controls the left side of the body
The left and right hemispheres are
connected by a large bundle of nerve
fibres called the corpus callosum. The
corpus callosum transfers information
between the two hemispheres
1m) Localisation of Brain Function
The cerebral cortex is the centre for conscious thought and contains 3 types of localised
functional areas: Sensory
(receives sensory impulses from receptors e.g. skin)
Association
(analyses, interprets & take decisions)
Motor
(sends motor impulses to muscles e.g. move hand)
Each cerebral hemisphere consists of
distinct areas which have a particular function to
perform e.g. speech motor area, auditory area,
visual area
Interconnections between each area occur due to
tiny nerve fibres. This allows for sophisticated
perception of a situation and the ability to make
an integrated response.
There are areas of the cerebral cortex that are
responsible for higher mental processes such
language, personality, imagination, creativity, conscience and intelligence
Neurobiology & Communication Questions
KEY AREA 1 - Divisions of the nervous system & parts of the brain
1.Testing Your Knowledge 1 Page 208
Q’s 1-4
2. Testing Your Knowledge 2
Page 219
Q’s 1-3
3.What you should know
Page 219
Q1-12
4.
Quick Quiz