KM
Krystal Mills
Answers (10)
KM
Answered
The somewhat different images of nearby objects received by our right and left eyes is known as
A) interposition.
B) accommodation.
C) retinal disparity.
D) linear perspective.
A) interposition.
B) accommodation.
C) retinal disparity.
D) linear perspective.
On Aug 01, 2024
C
KM
Answered
Short,persistent,usually nonverifiable tales with an ironic or supernatural twist are known as
A) gossip.
B) rumours.
C) urban legends.
D) mass hysteria.
A) gossip.
B) rumours.
C) urban legends.
D) mass hysteria.
On Jul 04, 2024
C
KM
Answered
Environmental factors such as viral infections can "turn on" specific genes that predispose schizophrenia.This best illustrates the impact of
A) an impaired theory of mind.
B) selective attention.
C) epigenetic factors.
D) positive symptoms.
A) an impaired theory of mind.
B) selective attention.
C) epigenetic factors.
D) positive symptoms.
On Jul 02, 2024
C
KM
Answered
What are nodes of Ranvier, and what role do they play in the conduction of nerve impulses?
On Jun 03, 2024
Nodes of Ranvier are small gaps in the myelin sheath of myelinated axons. They are named after the French pathologist Louis-Antoine Ranvier, who discovered them in the late 19th century. These nodes are crucial in the conduction of nerve impulses, particularly in vertebrates.
The myelin sheath is a fatty layer that covers the axon of many neurons, providing electrical insulation and increasing the speed at which electrical impulses (action potentials) travel along the neuron. However, the myelin sheath is not continuous; it is segmented, with the nodes of Ranvier being the tiny gaps between these segments.
The role of the nodes of Ranvier in nerve impulse conduction is based on a process called saltatory conduction. In myelinated axons, the action potential does not travel down the axon in a continuous wave but rather jumps from one node to the next. This happens because the myelin sheath prevents ions from flowing across the axon's membrane where it covers the axon, so the electrical impulse can only occur at the nodes where the axon is exposed.
At each node of Ranvier, the axon membrane is rich in ion channels, which allow sodium (Na+) and potassium (K+) ions to flow in and out of the neuron when the membrane potential reaches a certain threshold. When an action potential reaches a node, the influx of Na+ ions depolarizes the membrane, which then triggers the next section of the axon to depolarize. This depolarization-repolarization process repeats at each node, causing the action potential to jump rapidly from node to node.
This saltatory conduction is much faster than conduction in non-myelinated axons, where the action potential must propagate continuously along the entire length of the axon. By jumping from node to node, the nerve impulse can travel at speeds of up to 120 meters per second, as opposed to a maximum of about 2 meters per second in non-myelinated axons.
In summary, the nodes of Ranvier are essential for the rapid and efficient transmission of electrical signals along myelinated nerve fibers. They enable saltatory conduction, which conserves energy and increases the speed of nerve impulse propagation, allowing for the rapid communication that is necessary for complex functions such as movement, sensation, and thought.
The myelin sheath is a fatty layer that covers the axon of many neurons, providing electrical insulation and increasing the speed at which electrical impulses (action potentials) travel along the neuron. However, the myelin sheath is not continuous; it is segmented, with the nodes of Ranvier being the tiny gaps between these segments.
The role of the nodes of Ranvier in nerve impulse conduction is based on a process called saltatory conduction. In myelinated axons, the action potential does not travel down the axon in a continuous wave but rather jumps from one node to the next. This happens because the myelin sheath prevents ions from flowing across the axon's membrane where it covers the axon, so the electrical impulse can only occur at the nodes where the axon is exposed.
At each node of Ranvier, the axon membrane is rich in ion channels, which allow sodium (Na+) and potassium (K+) ions to flow in and out of the neuron when the membrane potential reaches a certain threshold. When an action potential reaches a node, the influx of Na+ ions depolarizes the membrane, which then triggers the next section of the axon to depolarize. This depolarization-repolarization process repeats at each node, causing the action potential to jump rapidly from node to node.
This saltatory conduction is much faster than conduction in non-myelinated axons, where the action potential must propagate continuously along the entire length of the axon. By jumping from node to node, the nerve impulse can travel at speeds of up to 120 meters per second, as opposed to a maximum of about 2 meters per second in non-myelinated axons.
In summary, the nodes of Ranvier are essential for the rapid and efficient transmission of electrical signals along myelinated nerve fibers. They enable saltatory conduction, which conserves energy and increases the speed of nerve impulse propagation, allowing for the rapid communication that is necessary for complex functions such as movement, sensation, and thought.
KM
Answered
Which statement best describes one criticism of the validity of IQ tests
A) IQ tests are not particularly valid for testing academic intellect but are valid for testing practical intelligence.
B) IQ tests are valid for measuring practical intelligence, but not social intelligence.
C) IQ tests are reasonably valid indexes of academic ability, but do not tap into other skills or traits that may be important for other forms of success.
D) IQ tests reflect a focus on academic success but do not adequately test for predictors of academic success.
A) IQ tests are not particularly valid for testing academic intellect but are valid for testing practical intelligence.
B) IQ tests are valid for measuring practical intelligence, but not social intelligence.
C) IQ tests are reasonably valid indexes of academic ability, but do not tap into other skills or traits that may be important for other forms of success.
D) IQ tests reflect a focus on academic success but do not adequately test for predictors of academic success.
On Jun 02, 2024
C
KM
Answered
Debbie wonders whether she should bother seeing a psychologist for her long-standing depression, as she has heard from two friends that they did not feel better after seeing a psychologist. To help inform her decision, her neighbor has just read a meta-analysis by Smith et al. (1980) in which their review of 475 studies revealed that the average person who receives therapy is better off at the end of it than __________% of persons who do not receive therapy.
A) 10
B) 25
C) 50
D) 80
A) 10
B) 25
C) 50
D) 80
On May 04, 2024
D
KM
Answered
Quantitative evaluation methods,such as questionnaires and survey,can capture the experience of intervention participants in a much more nuanced way than qualitative evaluation data.
On May 03, 2024
False
KM
Answered
Accepting ourselves without undue dependence on the approval of others best illustrates
A) reciprocal determinism.
B) possible selves.
C) positive psychology.
D) secure self-esteem.
A) reciprocal determinism.
B) possible selves.
C) positive psychology.
D) secure self-esteem.
On May 01, 2024
D
KM
Answered
Rumination is
A) compulsive fretting and overthinking about problems and their causes.
B) denial about having any depressed feelings.
C) explaining our own failures in terms that are global,stable,and internal.
D) the tendency to recall experiences that are consistent with one's current good or bad mood.
A) compulsive fretting and overthinking about problems and their causes.
B) denial about having any depressed feelings.
C) explaining our own failures in terms that are global,stable,and internal.
D) the tendency to recall experiences that are consistent with one's current good or bad mood.
On Apr 30, 2024
A
KM
Answered
People have difficulty understanding a statement like "She is not unfriendly" because
A) she may, in fact, be friendly.
B) double negatives are difficult to understand.
C) most people are basically unfriendly.
D) language is productive rather than interpretive.
A) she may, in fact, be friendly.
B) double negatives are difficult to understand.
C) most people are basically unfriendly.
D) language is productive rather than interpretive.
On Apr 29, 2024
B