Lee Haynes Flashcards
What are the functions of the nervous system?
Sensory, transmits, integrative, motor
The sensory function:
gathers information both from the outside world and from inside the body
the nervous system transmits….
the information to the processing area of the brain and spinal cord
the integrative function:
Processes the information to determine the best response
The motor function:
sends information to muscles, glands and organs (effectors) so they can respond correctly. Muscular contraction or glandular secretions.
Satellite cells
surround the neuron cell bodies in ganglia and regulate O2, CO2, nutrient and neurotransmitter levels around neurons in ganglia
Schwann cells
Surround axons in PNS, are responsible for myelinations of peripheral axons and participate in repair processes after injury
Oligodendrocytes
Myelinate CNS axons and provide structural framework
Astrocytes
maintain blood-brain barrier, provide structural support, regulate ion, nutrient and dissolved gas concentrations, absorb and recycle neurotransmitters and form scar tissue after injury
Microganglia
remove cell debris, wastes and pathogens by phagocytosis
Ependymal cells
line venticles (brain) and central canal (spinal cord) and assist in producing, circulating and monitoring of cerebrospinal fluid
In terms of neuronal circuits, what is divergence?
the spread of information from one neuron to several
In terms of neuronal circuits, what is convergence?
where information is spread from multiple sources to a single neuron
In terms of neuronal circuits, what is serial processing?
where neurons or pools work sequentially
In terms of neuronal circuits, what is parallel processing?
where neurons process information simultaneously
What acts as a minor coordinating centre (sometimes simple reflexes)?
the spinal cord
what is the meninges?
where both the brain and the spinal cord are covered in three continuous sheets of connective tissue
In the spinal cord, where is the grey and white matter situated?
inside and surface respectively
In the brains of mammals, where is the white and grey matter situated?
inside and the surface respectively. This is the opposite to the spinal cord.
What is the role of the cerebrum?
conscious thought, intellect, sensations, memory and complex movements.
what is the role of the diencephalon
THALAMUS: relay and processing sensory information. HYPOTHALAMUS: emotions, autonomic functions and hormone production
What is the role of the midbrain?
Maintenance of consciousness and visual and auditory data.
what is the role of the PONS?
connects the cerebellum to the brain stem and subconscious visceral and somatic reflexes.
What is the role of the medulla?
It connects the brain to the spinal cord and is the autonomic centre of visceral function
What is the role of the cerebellum?
Coordinates and adjusts complex somatic motor activity.
The brain receives nerve impulses from
the spinal cord
The ventral root in the spinal cord carries
efferent (motor) information to the muscles and glands
the grey matter of the spinal cord consists of
cell bodies of interneurons and some efferent neurons
the dorsal root of the spinal cord carries
sensory (afferent) information to the CNS
The white matter of the spinal cord consists of
axons carrying information through the spinal cord and to the brain
The assembly of a motor neurone plus all of the muscle fibres innervated by it is called a
motor unit
Somatic motor reflexes are:
the fastest reflexes, use myelinated axons, situated in one segment of the spinal cord or one nucleus of the brain, can be monosynaptic or polysynaptic,
What does the autonomic nervous system (ANS) do?
regulates the organs (the ‘viscera’) of our body, such as the heart, stomach, intestines etc and it functions in an involuntary, reflexive manner.
What is the ANS regulated by?
the hypothalamus and the medulla
The somatic nervous system is
voluntary, conscious control is requires, one efferent neuron and the effector organs are skeletal muscles
The autonomic nervous system is
involuntary, the effector organs are smooth muscle, cardiac muscle and glands, require two efferent neurons and ganglia and is under non-conscious control (hypothalamus, medulla)
The adrenal medulla releases
adrenaline (epinephrine) and noradrenaline (norepinephrine)
