Unit 3: Neurobiology & Immunology - Key Area 1 + 2: Divisions of The Nervous System and Neural Pathways, The cerebral cortex

Question 1

What are the 2 main parts the nervous system can be broken down into?

Answer 1

The central nervous system (CNS)and the peripheral nervous system (PNS).

Question 2

What makes up the central nervous system?

Answer 2

The brain and the spinal cord?

Question 3

What makes up the peripheral nervous system?

Answer 3

The somatic and autonomic nervous system.

Question 4

What makes up the autonomic nervous system?

Answer 4

The sympathetic and parasympathetic system.

Question 5

What does the somatic nervous system contain?

Answer 5

Sensory and motor neurons.

Question 6

What do sensory neurons do?

Answer 6

Sensory neurons take impulses from sense organs to the CNS.

Question 7

What do motor neurons do?

Answer 7

Take impulses from the CNS to muscles and glands. Which leads to the appropriate contractions by muscles or secretions from glands.

Question 8

What is the pathway of the somatic nerve?

Answer 8

Receptors (e.g. sense organs) ➡️ Sensory neurons ➡️ CNS ➡️ Motor neurons ➡️ effectors (e.g. muscles and glands).

Question 9

Is the somatic nervous system voluntary or involuntary and what does this mean?

Answer 9

Voluntary meaning under the conscious control of the brain.

Question 10

Where do impulses originate from in the autonomic nervous system?

Answer 10

The medulla.

Question 11

What does the autonomic nervous system consist of?

Answer 11

The sympathetic and parasympathetic systems.

Question 12

How do the parasympathetic and the sympathetic systems work and what does this mean?

Answer 12

They work antagonistically which means that they affect many of the same structure but have the opposite effects on them.

Question 13

What does the sympathetic system do generally?

Answer 13

It prepares the body for action (fight or flight).

Question 14

What does the parasympathetic system do in general?

Answer 14

It rests and relaxes the body for rest and digest.

Question 15

Is the autonomic nervous system voluntary or involuntary and what does this mean?

Answer 15

Involuntary meaning done without will or conscious control.

Question 16

What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of heart rate?

Answer 16

Sympathetic increases cardiac output. Parasympathetic decreases cardiac output.

Question 17

What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of breathing rate?

Answer 17

Sympathetic increases intake of air. Parasympathetic decreases intake of air.

Question 18

What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of peristalsis?

Answer 18

Sympathetic decreases the rate of peristalsis. Parasympathetic increases the rate of peristalsis.

Question 19

What is the antagonistic action of the sympathetic and parasympathetic systems on the effect of the production of intestinal secretions?

Answer 19

Sympathetic decreases production of intestinal secretions. Parasympathetic increases production of intestinal secretions.

Question 20

What does the sympathetic system do in general?

Answer 20

prepares the body for action (fight or flight).

Question 21

What does the parasympathetic system do in general?

Answer 21

relax the body for rest and digest.

Question 22

What are neurons?

Answer 22

The cells of the nervous system.

Question 23

What does converge mean?

Answer 23

To come together and meet at a common point.

Question 24

Where do converging pathways occur?

Answer 24

Converging pathways occur where impulses from several neurons travel to one neuron.

Question 25

What do converging neural pathways do?

Answer 25

Converging neural pathways increase the sensitivity to excitatory or inhibitory signals.

Question 26

What is an example of a converging neural pathway?

Answer 26

An example is where the neurons from rods in the retina/eye converge - this increases sensitivity to low levels of light.

Question 27

What does to diverge mean?

Answer 27

To branch out from a common point.

Question 28

What happens in a diverging neural pathway?

Answer 28

Impulses from one neuron travel to several neurons, therefore affecting more than one destination at the same time.

Question 29

What is an example of a diverging pathway?

Answer 29

The fine motor control in the fingers.

Question 30

What does reverberation mean?

Answer 30

Reverberation means a sound that occurs repeatedly, as in an echo.

Question 31

What happens in reverberating pathway and what does this allow to happen?

Answer 31

Neurons later in the pathway link with branching neurons, sending the impulse back through the pathway. This allows repeated simulation of the pathway.

Question 32

What are reverberating pathways used in?

Answer 32

Repetitive activities such as breathing.

Question 33

What does ‘fight or flight’ mean?

Answer 33

Preparation of the body to produce more energy.

Question 34

What is the arrangement of neurons in a converging neural pathway?

Answer 34

Several neurons to one.

Question 35

What are the 3 different parts of the brain?

Answer 35

The cerebral cortex, the limbic core and the central core.

Question 36

Where is the cerebral cortex in the brain?

Answer 36

The very top and is very large.

Question 37

Where is the limbic core in the brain?

Answer 37

The layer in between the outer cerebral cortex and the inner central core.

Question 38

Where is the central core of the brain?

Answer 38

The most inner part of the brain.

Question 39

What is the cerebral cortex and what does it do?

Answer 39

The cerebral cortex is the centre of conscious thought. It also recalls memories and alters decisions in the light of experience.

Question 40

What is there of the brain functions in the cerebral cortex and what does this mean?

Answer 40

There is localisation of brain functions in the cerebral cortex. This means it is made up of distinct regions, each of which has a particular function/role to perform.

Question 41

What does the localisation of brain functions in the cerebral cortex contain?

Answer 41

• Sensory areas (receive information from the body’s receptors).
• Association areas (analyse and interpret these impulses).
• Motor areas (receive information from association areas and send motor impulses to effectors e.g. muscles).
• There are also association areas involved in language processing, personality, imagination and intelligence.

Question 42

How is information from one side of the body processed and give an example of this?

Answer 42

Information from one side of the body is processed in the opposite side of the cerebrum. For example the left cerebral hemisphere deals with information from the right visual field and controls the right hand side of the body.

Question 43

How are the 2 hemispheres of the brain connected?

Answer 43

The 2 hemispheres of the brain are connected by a large bundle of fibres called the corpus callosum.

Question 44

What does the corpus callosum mean for the brain.

Answer 44

Whatever happens in one side of the brain is quickly communicated to the other side thereby coordinating brain functions and enabling the brain to act as an inter grated whole.

Question 45

What does localisation of function mean?

Answer 45

The cerebral cortex is made up of distinct sections which each have a particular function to perform.