Biological Psychology 4.0? Last one Promise

Neurons and glia

What are the two main types of cells in the nervous system?

Gene expression

What defines the type and functions of nervous system cells?

25%

The brain accounts for 2% of body mass but uses what percentage of daily energy?

86 billion

Approximately how many neurons are in the human brain?

Electrical and chemical

What type of signals do neurons use for communication?

Synapses

Where does communication between neurons occur?

Afferent

Which neuron type carries messages towards the brain and is sensory neurons?

Efferent

Which neuron type carries messages away from the brain? and is motor neurons

Interneurons

Which neurons carry messages between other neurons?

Dendrites

Receive signals

Soma

Cell Body

Axon

Transmit signals

Myelin Sheath

Insulating layer

Node of Raniver

Gap between the myelin sheath and lets the electrical signal jump form node to node

Axon Terminal

End of the axon: releases neurotransmitters to send the signal to the next cell

Nerve glue

What does the term 'glia' literally mean?

Glia

Support neuronal signaling, provide nutrients, and guide neurons in development and is non-electrical

30-60%

What percentage of total brain mass is composed of glia?

True

Glial cells are non-electrical.

Astrocytes

Which glial cell maintains the blood-brain barrier, synaptic functions, energy and metabolism and dvelopment?

Microglia

Which glial cells act as the 'immune system' in the brain, eliminate synapses, and provide signaling to other cells?

Oligodendrocytes

Which glial cell myelinates the Central Nervous System (CNS)?

Schwann cells

Which glial cell myelinates the Peripheral Nervous System (PNS)?

Microglia

Glial cells that eliminate synapses are called

Guide neurons

What is a primary function of astrocytes regarding development?

Brain

Spinal cord

What are the two components of the Central Nervous System (CNS)?

Sensory nerves

What are the components of the Peripheral Nervous System (PNS)?

Somatic nervous

Which system carries information to the CNS via sensory nerves?

Sensory Nerves

Carry information to the CNS

Motor Nerves

Carry information from the CNS to the muscles

Sympathetic

Which division of the PNS is responsible for the 'fight or flight' response?

Parasympathetic

Which division of the PNS is responsible for 'rest and digest'?

12

How many pairs of cranial nerves are there?

Vagus nerve

Which cranial nerve is specifically mentioned as innervating the gut?

Neural circuit

What is a group of neurons connected by synapses that process specific information?

1.Sensory neuron

2.Spine interneuron

3.Motor neuron

4.Muscle contraction

Order the components of a simple reflex circuit:

Bilateral symmetry

What term describes the mirror-image nature of the brain hemispheres?

Dura, arachnoid, pia mater

What are the three layers of the meninges?

Dorsal horn

In the spinal cord, which horn contains sensory interneurons?

Ventral horn

In the spinal cord, which horn contains motor neurons?

Dorsal/ventral root

Axons emerge in bundles

Spinal cord

Tracts carry sensory and motor information to/from brain

31

How many pairs of spinal nerves exit between the vertebrae?

Cerebral spinal fluid (CFS)

-Cushions and protects the brain

-Exchanges material between the blood and the brain

Choroid plexus

What tissue makes cerebrospinal fluid (CSF)?

1. Lateral ventricles

2. 3rd ventricle

3. 4th ventricle

4. Central canal

Order the directional flow of CSF:

Vascular system

-Provides nutrients/energy

-Carries away waste

Gray Matter

-Cell bodies

-Dendrites

White Matter

Myelinated axon

Volts

What unit is used to measure electrical potential across a membrane?

Amps

What unit is used to measure the flow of charge (current)?

Siemens

What unit is used to measure conductance?

-70 mV

What is the typical resting potential of a neuron?

True

At rest, a neuron contains more negative charges than positive charges inside.

It increases

What happens to the membrane potential when a neuron gains positive charges?

It decreases

What happens to the membrane potential when a neuron gains negative charges?

Na+

Cl-

Ca2+

Which ions are high in the extracellular fluid at rest?

K+

Which ion is high in the intracellular fluid at rest?

Ion pumps

What protein machines use ATP to move ions against their gradient?

Ion channels

What protein machines provide selective, passive gateways for ions?

+52 mV

At what membrane potential is the influx of Na+ equally opposed by repulsion?

diffusive force

The force that pushes K+ out of a typical neuron is the

True

Ion pumps and ion channels are both transmembrane and selective.

ATP

What energy source do ion pumps require?

7,000

How many synaptic partners does a typical neuron have?

400

Up to how many messages per second can a neuron send?

Presynaptic terminal

What is the term for the sending side of a synapse?

Postsynaptic terminal

What is the term for the receiving side of a synapse?

Glutamate

GABA

Dopamine

Serotonin

Which of the following are neurotransmitters?

Na+

What does EPSP stand for?

Cl-

Which ion influx typically causes an IPSP?

More likely

What happens to the likelihood of an action potential during an EPSP?

Less likely

What happens to the likelihood of an action potential during an IPSP?

Electrical synapse

What type of synapse allows signals to pass in both directions?

Connexon

What physical bridge connects neurons in an electrical synapse?

Returns to rest

What happens to a neuron if it does not reach threshold?

Spatial summation

The summation of EPSPs from two different synapses is called

Temporal summation

The summation of EPSPs from one synapse over time is called

~1 ms

Approximately how long do EPSPs and IPSPs last?

Threshold

What must be reached for an action potential to be triggered?

Rising phase

In which phase does the membrane potential become positive?

Falling phase

In which phase does the membrane potential switch back to negative?

Undershoot

What is the term for the membrane potential dipping below rest?

Absolute refractory period

What is the period when a neuron cannot fire again?

Voltage-gated Na+ channels

Which channels are critical for the action potential wave?

K+ exit

What drives repolarization during an action potential?

Firing frequency

How is information encoded in action potentials?

True

Motor neurons are spontaneously active.

Fires less frequently

What happens to motor neuron firing when receiving inhibitory input?

Saltatory conduction

What term describes action potentials jumping between nodes of Ranvier?

Increases speed

What is the effect of myelin on conduction speed?

~100

Approximately how many EPSPs are needed to trigger an AP in a cortical neuron?

False

Action potentials can move both forward and backward down an axon.

Hyperpolarization

What resets the voltage-gated Na+ channels?

Nodes of Ranvier

Where are voltage-gated channels most densely packed in myelinated axons?

Gets smaller

What happens to the signal size as graded potentials spread?

Axon hillock

Which location's proximity determines the strength of an EPSP's effect?

1. Resting potential

2. Threshold

3. Rising phase

4. Falling phase

5. Undershoot

Order the phases of an action potential:

Medial

Closer to midline

Lateral

Farther from midline