4.1.1 Structure Vertebrate Nervous System 2 Flashcards
The cell bodies of the sensory neurons are in clusters of neurons outside the spinal-cord, called the ____ ____ ____.
dorsal root ganglia
The H-shaped ____ ____ in the centre of the spinal cord is densely packed with cell bodies and dendrites.
gray matter
Many neurons of the spinal-cord send exons from the grey matter to the brain or other parts of the spinal cord through the ____ ____, which consists mostly of myelinated axons.
white matter
The ____ ____ ____ consists of neurons that receive information from and send commands to the heart, intestines, and other organs.
autonomic nervous system
The autonomic nervous system has two parts: the ____ and ____ nervous systems.
sympathetic and parasympathetic
The ____ ____ ____, a network of nerves that prepare the organs for vigourous activity, consists of chains of ganglia just to the left and right of the spinal-cords central regions.
sympathetic nervous system
Sympathetic axons prepare the organs for “____ or ____” – increasing breathing and heart rate and decreasing digestive activity.
fight or flight
The ____ ____ ____ facilitates vegetative, nonemergency responses.
parasympathetic nervous system
The term para means “beside” or “related to”, and ____ activities are related to, and generally the opposite of the sympathetic activities.
parasympathetic
The parasympathetic nervous system is also known as the ____ system because it consists of the cranial nerves and nerves from the sacral spinal-cord.
craniosacral
Long ____ axons extend from the spinal-cord to parasympathetic ganglia close to each internal organ. Shorter ____ fibres then extend from the parasympathetic ganglia into the organs themselves.
preganglionic : postganglionic
Parasympathetic activity decreases heartrate, increases digestive rate, and in general, ____ ____.
conserves energy
The parasympathetic nervous systems postganglionic axons release the neurotransmitter ____. Most of the postganglionic synapses of the sympathetic nervous system use ____.
acetylcholine : norepinephrine
Because the two systems, the PNS and the SNS, ues different transmitters, certain drugs ____ or ____ one system or the other.
excite or inhibit
The brain has three major divisions: ____, the ____, and the ____.
hindbrain, midbrain, forebrain
The hindbrain, the posterior part of the brain, consists of the ____, the ____, and the ____.
medulla, pons, cerebellum
The medulla and pons, the midbrain, and certain central structures of the forebrain constitute the ____.
brainstem
The ____, or medulla oblongata, is just above the spinal-cord and can be regarded as an enlarged extension of the spinal-cord into the skull.
medulla
The medulla controls vital reflexes – including breathing, heart rate, vomiting, salivation, coughing, and sneezing – through the ____ ____, which control sensations from the head, muscle movements, and much of the parasympathetic output to the organs.
cranial nerves
Just as the lower parts of the body are connected to the spinal-cord by sensory and motor nerves, the receptors and muscles of the head and organs connect to the brain by ____ pairs of cranial nerves.
- One of each pair on the right side and one on the left.
The ____ lies anterior and ventral to the medulla.
pons
In the pons, axons from each half of the brain cross to the opposite side of the spinal-cord so that the left hemisphere controls muscles on the ____ side of the body and the right hemisphere controls the ____ side.
right : left
Then the door and ponds also contains the ____ ____ and the raphe system.
reticular formation
The reticular formation has ____ and ____ portions. The descending portion is one of several brain areas that control the motor areas of the spinal-cord. The ascended portion sends output to much of the cerebral cortex, selectively increasing arousal and attention in one area or another.
descended and ascending
The ____ ____ also sends axons too much of the forebrain, modifying the brain’s readiness to respond to stimuli.
raphe system
The ____ is a large hindbrain structure with many deep folds. It is long been known for its contribution to the control of movement.
cerebellum
The ____ is in the middle of the brain, although in adult mammals it is dwarfed and surrounded by the forebrain.
midbrain
The roof of the midbrain is called the ____.
Tectum
The swelling is on each side of the tectum are the superior ____ and the inferior ____. Both are important for sensory processing – the inferior ____ for hearing and the superior ____ for vision.
colliculus
Under the tectum lies the ____, the intermediate level of the midbrain.
tegmentum
The tegmentum includes the nuclei for the ____ and ____ ____ nerves, parts of the reticular formation, and extensions of the pathways between the forebrain and the spinal-cord or hindbrain.
third and fourth cranial nerves
Another mid brain structure, the ____ ____, gives rise to a dopamine-containing pathway that facilitates readiness for movement.
substantia nigra
