Nervous System Flashcards
wat is the primary function of the nervous system
to rapidly transmit signals throughout the body coordinating perception, responses and behaviors
what are the two main divisions of the nervous system
central nervous system and peripheral nervous system
what are the two sub divisions of the autonomic nervous system
sympathetic division and parasympathetic division
what is the function of the sympathetic division of the autonomic nervous system
activates responses during stress of activity
what is the function of the parasympathetic division of the autonomic nervous system
controls body functions at rest
what are cranial nerves
nerves that emerge in pairs directly from the rain
what are spinal nerves
nerves that emerge bilaterally from the spinal cord
What are the three main parts of a neuron?
Soma (cell body), dendrites (receive signals), and axon (transmits signals).
What is the function of synapses?
They allow communication between neurons or between neurons and effector cells
How does neural signaling differ within and between neurons?
Within neurons: Electrical signals; Between neurons: Chemical signals (neurotransmitters).
What type of cells provide structural and metabolic support to neurons?
Glial cells.
Which group of animals lacks a nervous system?
Sponges.
What are the three types of nervous system organization in animals?
No nervous system, nerve net, bilateral nervous system.
What are ganglia, and what is their function?
Clusters of neurons and glial cells that receive sensory inputs and transmit signals to effectors.
Which invertebrate has the most complex brain?
The octopus (cephalopods have well-developed brains and large optic lobes).
What type of nervous system do arthropods have?
A “ladder-type” central nervous system with paired ganglia connected by ventral nerve cords.
What are the three major ganglia in an insect’s brain?
Protocerebrum (vision), deutocerebrum (antennae sensory input), tritocerebrum (internal organ control).
What are the two main components of the vertebrate CNS?
Brain and spinal cord.
What are the three layers of meninges in mammals?
Dura mater, arachnoid, pia mater.
What is the function of cerebrospinal fluid (CSF)?
Protection, cushioning, and nutrient transport for the CNS.
What are the three main sections of the brain?
Hindbrain (basic functions & movement), midbrain (sensory processing), forebrain (complex behavior & homeostasis).
Which brain region links the nervous system to the endocrine system?
The hypothalamus.
Which vertebrates have only two layers of meninges?
Amphibians, reptiles, and birds.
What brain adaptation allows fish like mormyrids to communicate and hunt?
They have unusually large brains for processing weak electric fields.
Which vertebrates have the largest brains relative to body size?
Birds like crows and parrots, and mammals.
Which brain structures are particularly large in reptiles compared to amphibians?
The cerebrum and optic lobes.
what is the resting potential in both invertebrates and vertebrates
-60mV to -70mV
which equation predicts changes in resting membrane potential
goldman-hodgkin-katz equation
what are the main types of voltage granted ion changes
na+ channels, k+ channels, ca2 channels
what are the key phases of a action potential
depolarization, upstroke, overshoot, repolarization, hyperpolarization
how does axon size affect action potential speed
larger axons propagate action potentials faster
what is myelin
Myelin is a fatty substance that insulates nerve fibers, allowing for fast and efficient transmission of electrical signals in the nervous system
what is the function of myelin in neural conduction
insulation of axons speeding up conduction and reducing energy costs
what is saltatory conduction
when action potentials jumps from one Node of Ranvier to another
what is a Node of Ranvier
A Node of Ranvier is a small gap in the myelin sheath of a nerve fiber that helps speed up the transmission of electrical impulses through saltatory conduction.
what is an action potential
An action potential is a rapid, temporary change in the electrical charge of a neuron’s membrane, allowing it to transmit a signal along the nerve fiber.
what are non-spiking neurons
neurons lacking voltage-gated sodium channels
where are non-spiking neurons found
in the central nervous system of vertebrates and invertebrates
what is the key difference between electrical and chemical synapses
electrical synapses are fast and direct chemical synapses use neurotransmitters
what structures facilitate electrical synapses invertebrates and vertebrates
connexons in vertebrates and exons in in vertebrates
what ion is essential for neurotransmitters release at chemical synapses
Ca2+
which protein are involved in vesicle fusion during neurotransmission release
syanptotagmin, synaptobrevin, ynatxin snap25
what are the two main types of postsynaptic receptors
ionotropic and metabotropic receptors
which type of neurotransmitter is used at the neuromuscular junction in vertebrates
acetylcholine
what are the two types of acetylcholine receptors
nicotinic and muscarinic
which neurotransmitter is connected from dopamine
noradrenaline
what is a neurotransmitter
Neurotransmitters are chemical messengers that transmit signals between nerve cells in the brain and nervous system, playing a crucial role in various bodily functions.
hat type of receptors to noradrenaline and adrenaline bind to
adrenoreceptors
which is the neurotransmitter in the most prevalent excitatory neurotransmission in the human brain
L-glutamate
what neurotransmitter is targeted by SSRI’S to treat depression
serotonin
what is the main inhibitory neurotransmitter in the vertebrate CNS
GABA
how to hormones differ from neural signals in terms of transmission speed
hormones act slower but cover longer distances
how does cocaine affect dopamine neurotransmission
it block dopamine reuptake leading to prolonged activation of nerval pathways
why are drugs like cocaine highly addictive
they cause permanent molecular changes in neurons leading to desensitization and dependance
what is the mechanism of action of strychnine
it competes with glycine at the postsynaptic receptors preventing glycine from inhibiting muscle contractions
how do environmental toxins impact honeybees
they impair learning and navigation affecting foraging behaviors
how does mercury poisoning affect the nervous system
disrupts neural development and functions leading to cognitive and motor impairments
What are some common venomous marine organisms that use neurotoxins?
Jellyfish, cone snails, venomous fish, stingrays, and sea snakes
what are two primary sources of neurotoxins in nature
they can be synthesized by organs or obtained through diet
How can neurotoxins be used in medical research?
They are studied to develop treatments for neurodegenerative diseases
