Nervous System Flashcards
Aqueous Humour
the clear fluid filling the space in front of the eyeball between the lens and the cornea
Axon
the long part of a neurone
Basal Ganglia
decision making part of the brain
Blind Spot
a spot at the back of the eye where the nerves join and light cannot reach
Central Nervous System
system that controls voluntary and involuntary reactions
Cerebellum
co-ordinates movement and balance and is important for voluntary tasks
Cerebrum
the largest part of the brain, divided into four lobes
Frontal Lobe
the lobe that lies immediately behind the forehead, controls areas concerned with behaviour, learning, personality and voluntary movement
Occipital Lobe
the rearmost lobe in the central hemisphere of the brain
Parietal Lobe
the lobe at the top of the head, concerned with reception and correlation of sensory information
Temporal Lobe
located underneath the temples, concerned with understanding speech
Cilary Muscles
pull the lens for focusing
Circular Muscles
muscles that contract causing the lens to constrict
CAT Scans
Computerised Axial Tomography Scans
scans that use a series of x-ray images from the different angles and a computer to produce cross-sectional images of the body’s internal structure
Concave Lens
a lens for short-sighted people that focuses the light on the retina and makes it converge later
Convex Lens
a lens for long-sighted people that focuses the light on the retina and makes it converge earlier
Coordination Centres
areas that receive information from receptors and send out signals to coordinate a response from the body
Cornea
lets light into the eyes and begins focusing
Cortex
outer layer of the cerebrum
Dendrites
a short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body
Effector
the part of the nerve that carries stimulus to muscles, organs and glands
fMRI Scans
scans that produce images related to the levels of oxygen in the blood and therefore to metabolic function, and hence, localised brain activity. These scanners produce images related to the water molecule’s hydrogen nuclei and therefore to anatomical structure. These are expensive and are mainly used for experimental research
Grey Matter
the darker tissue of the brain comprimising mainly of nerve cell bodies and dendrites
Hippocampus
where new memories are stored in the brain before going to long-term memory
Hippocrates
the first person to believe that senses were linked to the brain
Homeostasis
a balancing act that attempts to keep everything as constant as possible, such as regulation of internal conditions of cells to maintain optimum conditions for functioning
Hyperopia
long-sightedness, where the focal point is behind the retina
Hypothalamus
part of the brain that controls things like body temperature, hunger, thirst and sleep
Impulse
a wave of electrical charge across a neurone
Iris
controls the amount of light entering the eye
Laboratory Stage
the first part of a drug trial, where drugs are first tested on computer models, then on human cells, which is where most fail due to toxicity, then onto animal trials, where side effects begin to be studied
Lens
focuses light on the retina
Macular Degeneration
when light-sensitive cells in the middle of the retina stop working
MRI
Magnetic Resonance Imaging
a study method that involves scanning the brain using powerful magnets and radio waves
Medulla
sits at the top of the spinal cord, closest to the central nervous system. It sends messages down the spinal cord, controls movement, relays sensory impulses, relays information from internal organs, controls the arousal, controls sleep, regulates blood pressure and controls digestion, breathing and heart beating
Motor End Plate
where a motor neurone ends
Myelin Sheath
a fatty protective coating that protects the axon in neurones
Myopia
shortsightedness, where the focal point is in front of the retina
Nerve
tissue made up of neurones
Motor Neurone
neurones that have impulses travel down the neurone fibre from the motor neurone cell body to the neurone endings in the muscle or gland
Relay Neurone
neurones that pass signals between nerves
Sensory Neurone
neurones that have impulses that travel down through the neurone fibre through a sensory neurone cell body to neurone endings in the central nervous system
Neurosurgeon
a doctor that specialises in brains
Neurotransmitters
a chemical substance released at the end of a nerve fibre by the arrival of a nerve impulse, that, by diffusing across the synapse, effects the transfer of one nerve to another
Optic Nerve
the nerve that sends signals from the eyes to the brain
Paul Broca
discovered that people with speech impediments often had lesions on the cerebral cortex, making him the first person to link a specific part of the brain to a specific function
Phineas Gage
a man who was working on the railway and was involved in an accident where a metal pole went through his head and survived, though he had a vastly different personality
Pupil
lets light through to the lens
Radial Muscles
muscles that constrict causing pupils to dilate
Receptors
cells that detect stimuli in an external environment
Reflex Actions
automatic protection
Replacement Lens
one of the most recent treatments for long- and short-sighted people, where an extra lens is added to permanently correct vision defects
Retina
a light-sensitive layer that sends signals to the optic nerve
Sclera
the white outer layer of the eyeball
Suspensory Ligaments
ligaments that hold the lens in place
Synapse
the microscopic gap between two neurones
Tapetum
also known as the choroid, a reflective layer in the eyes of some animals, making them shine in the dark
Vitreous Humour
the transparent gelatinous tissue filing the eyeball behind the lens
White Matter
the paler tissue of the brain and spinal cord, consisting mainly of nerve fibres with their myelin sheaths
