Neuroanatomy Flashcards
What is radial symmetry?
tissues are developed in a radial fashion (body parts are arranged around a central axis), no front/back or left/right
What is bilateral symmetry?
organisms can be divided into two almost symmetrical halves (distinguishable front/back and left/right)
Do sponges have a nervous system? What is found in sponges?
No
genes for synaptic proteins are found
When do nervous system that resemble those that we see today?
530 million years ago
What types of proteins help the nervous system function? How do they do this?
channel proteins (facilitate ion flow), receptors (detect changes and convert this into an electrical signal), structural proteins (give shape, help form the synapse)
What is an example of the most primitive nervous system?
Hydra, called a nerve net, unorganized and all over the place like a net
How did the nervous system change from a hydra to a starfish?
radial symmetry is found, more organized, has a nerve ring in the middle with nerves reaching out to the tips
What is the difference between the nervous system of a sea star to a flatworm?
gained bilateral symmetry, there is specialization for the head and tail region, there are transverse nerves that connect two parallel columns
What is the difference between distributed nervous system and centralized nervous system?
centralized nervous system is organized with the main points at the center (brain, spinal cord) and nerves branching out to the rest of the body
distributed nervous system (like squid) is where the control center of the nervous system is distributed throughout the body (tentacles of squid are like brain)
Did brains evolve to get bigger? Why or why not?
No
they evolved to get more folded so we can fit more neurons into the same space
How can you determine the reason for a certain part of the brain having evolved to be bigger/folded?
it might be bigger because they need it more
ie. fish have bigger optic regions b/c prey, reptiles have a longer olfactory bulb because they rely on sense of smell, more folded cerebellum might mean that they ar animals that move faster
How do most brain develop folds? What is the exception? How does it develop folds?
most develop folds inward (called evagination)
the exception is fish, they develop fold outward (called eversion, brain essentially pushes out and around til it folds back onto itself)
Is brain size, gene expression, or gene complexity the reason we are smarter?
no, our brains are not the biggest, size does not equal smart
no, most of our genes are expressed throughout the body
no, we don’t have the most complex genome
What is a connectome?
complete map of the neural connections in the nervous system of an organism
What is gyrus vs sulcus?
gyrus is the outer fold and sulcus is the inner groove
What is lissencephaly?
rare, gene-linked, brain malformation charaterized by the absence of folds
smooth brain
Why are some birds very intelligent?
the density of the neurons in the forebrain is very high (have smaller neurons so more can fit)
What are the two parts of the nervous system?
central nervous system and peripheral nervous system
What is the cervical enlargement and lumbosacral enlargement? What are there function?
around the cervical vertebrae and near the lumbar vertebrae the spinal cord is enlarged (wider)
because the arms and the legs are located there so wider spinal cord needer for the extra sensory/motor info (specialization)
What are the names of all the vertebrae?
Cervical: C1-C8 (C8 is only spinal nerve)
Thoracic: T1-T12
Lumbar: L1-L5
Sacral: S1-S5
Coccygeal: Coc1 (tailbone)
Where does the spinal cord end? What is there instead?
Around L1-L2, turns into nerve filaments and cerebral spinal fluid (where they poke for lumbar puncture)
What are examples of some external signals? What detects them?
hearing, vision, smell, taste, touch, equilibrium (how we keep track of our body parts)
sensory organs
What are some examples of internal signals?
signals that are generated inside the body
internal temperature, blood pressure, oxygenation
What is the autonomic nervous system?
part of the peripheral nervous system, regulates involuntary physiological processes (we can’t control it)
What are the parts of the autonomic nervous system? Explain briefly their purpose?
sympathetic (activation): prepares body for fight/flight
parasympathetic (resting): calms body down after fight/flight
enteric: regulates the gut, digestion, absorption of nutrients
What is the somatic nervous system?
nervous system consisting of muscles that you can use and control (skeletal)
What is the sylvian fissure?
separates the temporal lobe from the frontal/parietal lobe
also called lateral fissure
What is the central sulcus?
separates frontal and parietal lobes and the primary motor cortex and primary somatosensory cortex
What are the lobes of the brain called?
frontal, parietal, occipital, temporal
What is the longitudinal fissure?
separates the left and right hemispheres
What is the main difference between MRI and CT scans?
CT uses a fast series of x rays and MRI uses magnetic field
What is hemisphere rotation?
the brain rotated on an axis so that we look forward when standing up
(point it rotated around is midbrain)
What is the corpus callosum?
bridge connecting the two hemispheres, connects areas of similar function
What is the diencephalon?
contains thalamus, hypothalamus, epithalamus, and subthalamus
What is the fornix?
output region of the hippocampus, connects hippocampus to the rest of the brain
What is the hippocampus? Where is it located?
helps form memories after info is processed
located deep in the temporal lobe
What is the function of the thalamus? What is the location?
almost all info in the brain is processed through the thalamus
above brainstem, below lateral ventricle
What are the parts of the basal ganglia? What is the function?
caudate, putamen, and globus pallidus
motor control, motor learning, also associated w/parkinsons
How can you determine if you are viewing the brainstem from ventral or dorsal view?
optic chiasm means ventral view
What does the location of the cranial nerves on the brainstem tell you?
the nerves that are closer to the outside are purely sensory, the ones closer to the inside are purely motor, and the ones in the middle do both