NSCI 1001 Unit One Exam

what are the physical characteristics of the brain?

average weight of 1300g; average volume of 1260 cm³; relatively 2% of total body mass

what are the functions of the brain?

acts as a processor of information; integrates the information received from the environment (through sensory organs) and itself; elaborates different biological responses that are executed by other organs (glands and muscles)

what is in the central nervous system?

brain, spinal cord

what is in the peripheral nervous system?

somatic nervous system, enteric nervous system, autonomous nervous system

what does the somatic nervous system do?

it controls voluntary movements, sensory, spinal, skeletal, muscles, and joints

what does the enteric nervous system do?

gut, intestinal movements

what does the autonomous nervous system do?

sympathetic controls fight or flight, parasympathetic controls rest and digest

what are nerves?

they are axon bundles. they transmit impulses of sensation to the brain or spinal cord, and impulses from these to the muscles and organs

what are the physical characteristics of the central nervous system?

hollow, filled with cerebrospinal fluids

ipsilateral

same side

contralateral

opposite side

how much body energy does the brain represent?

20%

systems

interconnected brain areas that control specific brain functions

circuits

interconnected neurons in different regions

networks

interconnected neurons in a brain region

neurons

nerve cells

synapses

specialized structure for neuronal communication

channels

membrane proteins tha control the flow of ions

ions

carry neuronal electrical signals

what are the levels of complexity of the nervous system

1m - nervous system

1 dm - systems

1 cm - circuits

1 mm - networks

100 μm - neurons

1 μm - synapses

1 nm - channels

1 Å - ions

what is a cell?

the structural, functional, and biological unit of an organism. they are the basic building blocks of our organs, and all living things are made of cells. our bodies have trillions

how big is a cell

10-100 μm

what are the components of the eukaryotic animal cell?

plasma membrane, cytoplasm, mitochondria, microtubules & filaments, ribosomes, endoplasmic reticulum

plasma membrane

outer boundary of the cell

cytoplasm

interior of the cell

mitochondria

powerhouse of the cell, produces energy

microtubules & filaments

form the cytoskeleton of the cell

ribosomes

organelles responsible for protein synthesis

endoplasmic reticulum

network of membranes

what are the cells in the nervous system

neurons, glial cells, astrocytes, oligodendrocytes, schwann cells, ng2+ cells, ependimocytes, microglia

what is 1?

neurons

what is 2?

oligodendrocytes

what is 3?

capillary vessel?

what is 4?

axon (enwrapped by myelin)

what is 5?

astrocyte

what is 6?

ependymocytes

what is 7?

microglia

what is the reticular theory?

the nervous system was considered to be formed by a continuous reticulum or network of cells fused together

what is the neuron doctrine?

the nervous system was considered to be formed by a continuous reticulum or network of cells fused together

what are neurons?

they are the elementary cellular unit of information processing. they are interconnected in structural and functional elements called synapses

what do astrocytes do?

structural support, neuronal survival, neuronal differentiation, neuronal guidance, neuritic outgrowth, synaptogenesis, trophic and metabolic support, extracellular homeostasis of ions and neurotransmitters, regulation of synaptic function and network activity, regulation of neurovascular coupling

what are dendrites?

a short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body

what are dendrite spines?

protrusions in dendrites that serve as the primary postsynaptic site for excitatory synapses.

what do oligodendrocytes do?

they form myelin in the central nervous system.

what do schwann cells do?

they form myelin in the peripheral nervous system.

what is myelin?

a fatty substance largely made by plasma membrane that covers many axons. dramatically increases the speed of electrical signal conduction down the axon.

what are ng2+ cells?

they are oligodendrocyte precurson cells in the central nervous system.

what are ependimocytes?

ciliated, epithelial-like glial cells of the central nervous system that line the brain ventricles and the spinal cord's central canal.

what are microglia?

immune cells of the CNS. they cover surveillance, debris clearance, and immune disease. they are involved in removing unnecessary synaptic structures.

the human brain has about…

80 billion neurons, 80 billion glial cells, and 1000 synapses per neuron (about 80 trillion synapses)

what is the size of the neuronal soma?

20 µm²

how long are dendrites?

from a few µm to mm

how long are axons?

from a few µm to meters

where are the somas of neurons found?

in the grey matter of the brain and spinal cord, dorsal root ganglia and visceral ganglia

what are the different properties a neuron can have?

morphology, electrical excitability, protein expression, function, roles in the network

individual cell

neuron (e.g., retinal ganglion cell, Purkinje neuron, etc.)

collection of neurons

nucleus (e.g., nucleus accumbens)

collection of nuclei

region (e.g., visual cortex)

interconnected neurons in a brain region

network (e.g., hippocampal network)

interconnected neurons in different brain regions

circuit (thalamo-cortical circuit)

interconnected brain areas that control specific brain functions

system (e.g., visual system)

yellow represents…

frontal bone

blue represents…

parietal bone

pink represents…

sphenoid bone

orange represents…

temporal bone

green represents

occipital lobe

red/dark orange represents…

ethmoid bone

what is a meninge?

a membrane that covers the brain and the spinal cord

what are the three meninges?

dura mater, arachnoid, pia mater

what is cerebrospinal fluid?

they are used for buoyancy/protection, as well as waste product removal. ventricles and spinal cord canal are filled with it.

what is neuroanatomy?

study of the structure and morphological organization of the nervous system

what is in the forebrain?

Brodmann areas, gyrification, olfactory bulbs, cortex lobes, basal ganglia, hippocampus, thalamus

brodmann areas

regions of the cerebral cortex, about 52

gyrification

cortical wrinkles provide a large surface area / volume ratio

olfactory bulb

responsible for our sense of smell

cortex lobes

frontal, parietal, temporal, occiptal

frontal lobe

Movement, judgment, impulse control

parietal lobe

Sensory processes, movement

temporal lobe

Hearing, language, emotion

occiptal lobe

vision

what is in the basal ganglia?

caudate nucleus, putamen, globus pallidus, subthalamic nucleus, ventral striatum (nucleus accumbens), substantia nigra (midbrain structure)

what are the functions of the basal ganglia

motor control, learning, decision-making, reward (function) motor deficits, schizophrenia, OCD, addiction (dysfunction)

ventral striatum

reward, motivation—causes drug addiction

hippocampus

navigation through space and time; episodic memories

amygdla

processes emotions, specially fear and anxiety, triggers "fight-or-flight" response, forms emotional memories, is a threat detector that links sensory input to emotional reactions and stress responses.

thalamus

relay info to cortex

hypothalamus

intercourse, eating, stress

what is in the midbrain?

Substantia Nigra, Periaqueductal gray matter, Raphe Nucleus, Ventral tegmental area, Inferior Colliculus, Superior Colliculus

substantia nigra function

movement

Periaqueductal gray matter function

pain

raphe nucleus funtion

mood & emotion

ventral tegmental area function

reward/motivation

inferior colliculus function

hearing

superior colliculus function

vision

what is in the hindbrain?

cerebellum, pons and medulla oblongata

cerebellum function

fine movements, posture, balance

pons and medulla oblongata function

Basic Bodily Functions: Sleep/wakefulness, breathing,

dendrites

receive information

cell body/soma

processes information

axon

conveys information