Physiology Lab Practical 1 practice

What will the cell become when Na+ enters?

Depolarized

What is the term used to describe the cell becoming more positive?

Depolarized

What will the cell become when Cl- enters?

Hyperpolarized

What is the term used to describe the cell becoming overly negative?

Hyperpolarized

What will the cell become when K+ leaves?

Hyperpolarized

What will the cell become when voltage-gated Na+ channels close?

Repolarized

What is the rpm of a human neuron?

\-70mV

Where is the greater concentration of Na+?

In the cell

Where is the greater concentration of K+?

In the cell

Where is the greater concentration of Cl-?

Outside the cell

Does repolarizing make the cell more positive or negative?

Negative

What is the threshold to open ion channels to trigger depolarization?

15mV above RMP

What will happen if external Cl- is lowered to zero?

Block repolarization

What will happen if external Cl- is raised to 1000 mM?

Faster repolarization

What will happen if the external K+ is lowered to zero?

Faster repolarization

What will happen if external K+ is raised to 400mM?

Block repolarization

What will happen to Na+ ions if a voltage higher than 55 mV is used?

Na+ ions will move out of the cell

What is the muscle that moves through the thigh and is responsible for the patellar reflex called?

Rectus femorus

What is the group of muscles in the thigh called?

Quadriceps femoris

What are the names of the two scientists who worked with the giant squid axon to learn about action potentials?

Hodgkin and Huxley

What is the name of the standard model of action potential called?

Hodgkin and Huxley model

What technique did Hodgkin and Huxley use in their experiment?

Voltage clamp technique

What apparatus was used by Hodgkin and Huxley for analyzing the giant squid axon?

Axon test chamber

What is the term used to describe the difference in electrical potential between two points?

Voltage potential

What is the term used to describe the difference in electrical potential between the inside and outside of the cell membrane?

Membrane potential

What is the term used to describe an event where electrical membrane potential of a cell rises and falls rapidly?

Action potential

What are the two types of channels involved in action potentials?

Sodium and potassium

Where are sodium and potassium channels located?

In the cell membrane

What channels open during depolarization?

Na+ channels

Will Na+ entering the cell make it more positive or negative?

Positive

What channels open during repolarization?

K+ channels

What channels close during repolarization?

Na+ channels

What brings the cell back to resting potential?

Repolarization

What ions flow out of the cell during hyper polarization?

K+

Will K+ flowing out of the cell make the cell more negative or positive?

Negative

What activates voltage gated ion channels?

Changes in membrane potential

What direction do K+ ions flow?

Out

What direction do Na+ ions flow?

In

Therapeutically, what are channel blockers used to prevent?

Neurodegenerative diseases

What are calcium channel blockers used to treat?

Hypertension

What are potassium channel blockers used to treat?

Arrhythmias

What are sodium channels used for?

Anesthesia and anti-convulsion

What ion channel blocker does not have therapeutic properties?

Cl-

What is a neurotoxin that blocks sodium channels?

Tetrodotoxin

What technique is used to study ion channels in living tissues, cells, or patches of the cell membrane?

Patch clamp technique

What technique is used to record current through the membrane of excitable cells while maintaining a fixed membrane voltage?

Voltage clamp technique

What is the technique used to record voltage of a cell following an electrical stimulus?

Current clamp technique

What are the bones of the skull that immediately cover and protect the brain surfaces?

Cranium

What is the thin cover of skin that covers most of the cranium?

Scalp

What is the largest part of the brain immediately beneath the bones of the cranium that are composed of neurons?

Cerebral cortex

What are nerve cells that are functionally connected to each other and connected to other parts of the brain?

Neurons

What does absence of electrical activity in the human cerebral cortex signify?

Cell death

What are the regions of the cerebral cortex?

Occipital lobe and parietal lobe

What lobe processes visual information?

Occipital

What lobe processes somatosensory information such as cutaneous pain or temperature?

Pariteal lobe

What are the regions of the brain?

Frontal, parietal, occipital, temporal, and cerebellum.

What are placed on the scalp to detect electrical activity associated with functioning neurons?

Electrodes

What is the recording of the brain’s activity obtained by using electrodes called?

EEG

What does EEG stand for?

Electroencephalogram

t/f: EEG electrode detects activity from the brain just underneath it

True

t/f: Electrodes receive information from 1 neuron

False

Who discovered that electrodes placed on the scalp can detect various patterns of electrical activity?

Hans Berger

What are the 4 rhythms recorded in the EEG?

Alpha, beta, delta, theta

What is the measurement of EEG rhythms?

Frequency

What are the frequencies of alpha?

8-13

What are the frequencies of beta?

13-30

What are the frequencies of delta?

1-5

What are the frequencies of theta?

4-8

What is the rhythm of an adult who is awake but relaxed with eyes closed?

Alpha

What regions of the brain are alpha frequencies recorded?

Occipital and partital lobes

What is the rhythm of individuals who are alert, attentive to external stimuli, and exert mental effort?

Beta

What does REM stand for?

Rapid eye movement sleep

t/f: beta rhythms are synchronized

False

t/f: beta rhythms are associated with memory

True

What are the rhythms of nREM

Delta and theta

What wave is present with difficult mental activities requiring concentration (not beta)?

Delta

What wave is present with emotionally frustrating events (not beta)?

Theta

What are three kinds of muscle tissue?

Skeletal, smooth, and cardiac

What EEG method uses two electrodes and a third for baseline?

Bipolar

Where is cardiac muscle found?

Heart

What type of muscle is located in the walls of hollow organs?

Smooth

What type of muscle is attached to the skeleton?

Skeletal

What is the term used to describe the hundreds of individually cylindrically shaped cells in muscles?

Fibers

What part of the nervous system stimulates skeletal muscles?

Somatic motor nerves

How many neurons can innervate a muscle fiber?

One

How many muscle fibers can be innervated by a neuron?

Many

What are the long cylindrical extensions of the neurons called?

Axons

What is a single motor neuron and all the muscle fibers it controls called?

Motor unit

What is the term used to refer to the increasing number of simultaneously active motor units within the muscle?

Motor neuron recruitment

What is the term used to describe the constant state of slight tension that serves to maintain the muscle in a state of readiness?

Tonus

What is the term used to describe the changing strength of muscle contraction/change in extent of shortening in proportion to the load placed on the muscle?

Grading

What is the term used to describe the detection, amplification, and recording of changes in skin voltage produced by underlying skeletal muscle contraction?

Electromyography

What is the recording of an electromyography called?

EMG

What does EMG stand for?

Electromyogram

t/f EMG spikes have negative and positive components due to propagation of the muscle consisting of depolarizing and repolarizing

True

Are Integrated EMG fibers more or less accurate?

More

What is the application of force resulting in the movement of an object called?

Mechanical work

Are AP’s sent in singles or trains?

Trains

t/f: The number of motor units are proportional to the amount of work done by the muscle

True

t/f: Recruiting different motor units give them time to relax

True