U4 Lecture 27 Flashcards
- list the divisions of the nervous system. what are the two major cell types within the nervous system and their basic functions - list the four major structures of the brain - describe the organization of the cerebrum in terms of gyri, sulci, hemispheres, lobes and grey and white matter - describe the organization of the cerebellum in terms of hemispheres and white and grey matter - list and describe the meningeal layers and spaces, in order from superficial to deep. Include a list of the
How many neurons is in our nervous system?
85 billion
Each neuron has what?
10 thousand synapses (contacts) with other neurons
What are the functions of the nervous system?
- Sensory function 2. integrative function 3. Motor Function
Describe the sensory function of the nervous system
Information goes back to the brain and spinal cord via cranial and spinal nerves
What types of neurons control the sensory function of the nervous system?
Afferent Neurons
Describe the integrative function of the nervous system
Integrates sensory information by analyzing and storing it
What types of neurons control the integrative function of the nervous system?
Interneurons
Describe the motor function of the nervous system
Information from the brain and the spinal cord is sent out to muscles or glands (effectors)
What type of neurons control the motor function of the nervous system?
Efferent neruons
What are the two branches of the Nervous System?
- Central Nervous System = brain and spinal cord
- Peripheral Nervous System = Cranial and Spinal Nerves
What are the three branches of the Peripheral Nervous System?
- Enteric NS
- Somatic NS
- Autonomic NS
Where is the enteric nervous system?
smooth muscle, glands of the GI tract
Where is the somatic nervous system?
skeletal muscle
Where is the autonomic nervous system?
Smooth muscle, cardiac muscle and glands
What are the two branches of the Autonomic Nervous system?
- Sympathetic division = fight or flight
- Parasympathetic division = rest and digest
What are the two cell types of Nervous tissue?
Neurons and Glial Cells (Neuroglia)
What do neurons do?
Involved in the generation and interpretation of ‘Electrical Signals’
What do neuroglia do?
Support neuronal cell activity
More specifically, what do glial cells do?
Insulate, support and nourish neurons
More specifically, what do neurons do?
Process information
Sense environmental and internal changes
Communicate changes to other neurons
Command body responses
What are the four major parts of a neuron?
Dendrites -> Cell body -> Axon -> Synapses
Function of dendrites
Collect information
Function of Cell body
Process information
Function of axon
spread information to output site
Function of synapses
Transmits information to other parts of the nervous system
What are membrane potentials
small electrical signals
What are the different charges of membranes potentials
- Resting potential - steady negative charge (don’t feel anything)
- Action potentials - “all or nothing” positive charge
What causes action potentials to charge membranes potentials
Graded voltage changes occur in response to sensory stimuli or synaptic inputs
What are the functions of the brain?
- Control center
- center of intelligence, behavior, memory and emotion
- Coordinates activity of skeletal muscles
- Influences activity of visceral organs and glands
What is the brain composed of?
85 to 100 neurons and even more neuroglia
How does the brain act as a processing center?
interpretation of sensory information is based on PATH TRAVELED and DESTINATION in the brain
What happens to the brain when we learn and develop new skills?
Plasticity = anatomical changes in the brain, new synapses form and new pattern of activity develops, also neurogenesis (new neurons)
What are the four major parts of the brain?
- Cerebrum 2. Cerebellum 3. Diencephalon 4. Brain Stem
What are the subdivisions of the Diencephalon?
Thalamus, hypothalamus, and epithalamus
What are the subdivisions of the brain stem?
pons, medulla oblongata, and midbrain
What is the organization of the cerebrum?
2 cerebral hemispheres - right and left
What is the right cerebral hemisphere responsible for?
music, face recognition, visual imagery, spatial abilities
What is the left cerebral hemisphere responsible for?
Language, logic, and reason
What are the different lobes in the brain?
Frontal, Parietal, temporal, occipital, and insula
What are the functions of the frontal lobe?
Reasoning, planning, speech and movement, emotions and problem solving
What are the functions of the parietal lobe?
Perception of stimuli related to touch, pressure, temperature and pain
What are the functions of the temporal lobe?
Perception and recognition of auditory stimuli and memory
What are the functions of the occiputal lobe
Vision
What are the functions of the insula lobe?
autonomic information (info from body to CNS)
visceral function (autonomic involuntary functions mediated by smooth muscle, cardiac muscle and glands)
Define gyrus
A ridge on the brain
Define sulcus
a small groove or fold in the brain
Define fissure
a large groove or fold in the brain
What are the main sulcus in the brain?
Central sulcus and the lateral cerebral sulcus
What are the main fissures in the brain?
Longitudinal fissure and the transverse fissure
What are the main gyrus in the brain?
Precentral gyrus and postcentral gyrus
What are the two parts of the cerebellum?
Cerebellar cortex and arbor vitae
What is the cerebellar cortex made of?
Grey matter
What is the arbor vitae made of?
White matter - looks like tree on cerebellum
Define meninges
Connective tissue coverings that surround the brain and spinal cord
Function of meninges
- protects underlying neural tissue
- anchors the brain in cranial cavity and spinal cord in vertebral cavity
What are the 3 layers of meninges?
- Dura matter = subdural space
- Arachnoid mater = subarachnoid space
- Pia mater
Characteristics of dura matter
Most superficial layer
- outer layer fuses w periosteum of skull (not w SC)
- inner later folds into parts of cranial cavity forming sinuses
Major dura matter folds
- Falx cerebri
- Falx cerebelli
- Tentorium cerebelli
CSF Pathway
Functions of cerebral spinal fluid
Cushioning and shock absorption
Chemical Protection
Exchange nutrients and waste
What is the brain blood barrier?
Protective mechanism that maintains stable environment for the brain
- Capillaries of the brain are the least permeable of any capiliaries in the body
- Capillaries are selective partly due to presence of astrocytes
What are astrocytes?
A type of neuroglia
