Past Exam Questions Flashcards
Give a function of the medulla oblongata
Controls involuntary actions such as coughing, swallowing or breathing
Give a function of the cerebellum
Controls voluntary movements
Controls posture
Controls coordination
Why is grey matter so called?
It is composed of cell bodies
Why is white matter so called?
It is composed of axons and myelin
Outline the role of dendrites.
They carry impulses to the cell body
Outline the role of axons.
They carry impulses away from the cell body
Outline the role of cell bodies.
Produces neurotransmitters
Receives an impulse from a dendrite and passes it to an axon
Controls the passage of an impulse
Describe how a nerve impulse is transmitted across a synaptic cleft, from one neuron to the next.
An impulse stimulates the neurotransmitter swellings in the pre-synaptic neuron to release a neurotransmitter which diffuses rapidly across the synaptic cleft
On the post-synaptic neuron the neurotransmitter is broken down by enzymes and reabsorbed back into the neurotransmitter swellings where they can be recycled.
Explain the importance of the myelin sheath in the transmission of a nerve impulse.
The myelin sheath speeds up the transmission of a nerve impulse
What is the main structural difference between white and grey matter?
Grey matter is composed of cell bodies while white matter is composed of axons and myelin
What is the function of the meninges?
To act as a shock absorber and protect the brain and spinal cord
How many layers are present in the meninges?
3
What is a reflex action?
An automatic involuntary, unthinking response to a stimulus
Outline the mechanism of reflex action
6 main points
- Receptors are stimulated
- Sensory neurons carry an impulse into the spinal cord through the dorsal root
- An interneuron carries the impulse across the spinal cord to a motor neuron
- Another neuron takes the impulse up to the brain
- Motor neurons take the impulse straight out of the spine through a ventral root to the effector muscle or gland
- At the same time the action is carried out the impulse reaches the brain which makes us aware of what has happened.
Name the type of particle whose movement in an out of neurons is an essential feature of nerve impulse transmission
Ion
Distinguish between the position of the cerebellum and the position of the cerebrum in the human brain
The cerebellum is the hindbrain
The cerebrum is the forebrain
State three functions of the cerebrum
Memory Learning Emotion Speech Vision Intelligence Movement Language Smell Hearing Logic Personality Taste
Distinguish between the central nervous system and the peripheral nervous system
The CNS consists of the brain and spinal cord
The PNS consists of nerve fibres outside the brain and spinal cord
Give one way in which a nerve response differs from a hormone response
Nerve responses are electrical, faster and shorter lived
Name and state the role of any two types of neuron, other than the motor neuron
Interneuron: A neuron which carries information between sensory and motor neurons
Found between motor and sensory neurons in the CNS
Sensory neuron: A neuron which takes a message from a sense organ to the CNS
State one function of the cerebrum
Language The senses Consciousness Reason Memory Intelligence Emotions ...
State one function of the hypothalamus
To regulate the internal environment of the body (homeostasis) by monitoring the body
To link with the pituitary gland to regulate the production of hormones
State one function of the cerebellum
Balance
Muscular coordination
Movement
State one function of the medulla oblongata
Breathing Blood pressure Swallowing Coughing Salivation Vomiting Sneezing
Name a possible cause of Parkinson’s disease
A disorder of the nervous system caused by the failure to produce dopamine in a part of the brain
How can Parkinson’s disease be prevented or treated?
There is no known way to prevent this disease
Initially physiotherapy and special exercises along with the provision of special aids and home help to patients
Treatment with drugs such as L-dopa stimulate or mimic dopamine which can reduce symptoms but does not stop the degeneration of the brain
Electrical stimulation or implanting dopamine-secreting tissue (stem cells) into the brain may prove beneficial
Give one example of a reflex action
The grasp reflex in children The movement of the iris of the eye Blinking the eyes for protection Breathing Control of blood pressure The protective actions we take when falling The knee jerk
Suggest an advantage of reflex actions
It is a fast response so it can protect the body from damage
What is the role of a motor neuron?
Takes a message from the CNS to a muscle or gland
What is a neuron?
A nerve cell
State a function for Schwann cells
To produce a myelin sheath
State a function of the myelin sheath
Insulates the electrical impulses of a neuron
