lab prac 2

What determines the peak on a muscle contraction graph?

the amount of amplitude in mv

What is total tension composed of?

active tension and passive tension

What generates active tension in a muscle?

involves energy: the binding of actin and myosin head

What generates passive tension?

tension/ force of recoiling of connective tissue

What is coactivation and why is it important?

the simultaneous activation of both agonist + antagonist at different force; it's important for joins stabilation

Define agonist muscle.

muscle that contract to move bones

Define antagonist muscle.

muscle that relaxes at contraction

What is the size principle in recruitment?

recruit more motor units that controls more muscle fibers in order of size, from smallest to largest

what is a motor unit

single motor neuron and al the musee fibers under thes

define a muscle twitch

a single contraction. the smallest motor unit

what causes wave summation

recruitment of more motor units to prevent going into relaxation

what is tetanus in muscle contraction

using all motor units and maximum capacity of energy and ca2+

What does the all-or-none principle state?

a muscle fiber contracts or not at all when threshold is renewed

what are the three phases of a muscle twitch

latency, contraction and relaxation

define areflexia

no reflexes at all

what is hyporeflexia

low reflex

what are characteristics of a reflex

rapid automatic(motor) and involuntary response

1. What kind of reflex involves only one synapse?

monosynaptic

1. What is a polysynaptic reflex?

2 synapses the inter neurons between sensory and motor

Define contraleral reflex.

sensory and receptor on the opposite side

Define ipsilateral reflex.

receptor and effector on the same side

What does a consensual reflex mean?

one side is stimulated and both side reflex

1. What kind of reflex is the knee-jerk reflex?

ipsilateral reflex

1. What is the Babinski sign and its normal response in adults?

it is a negative response and toes go down

1. Which cranial nerve controls pupillary reflex?

occulomotor cn iii size of pupils

1. What nerve carries the corneal reflex?

trigeminal nerve v cornea to brain

1. What causes color blindness?

x- linked gene mutations

1. Where is the blind spot located?

where the optic nerve exits and the nerve and retina connects

What is myopia?

elongated eyeballs condition where close objects appear clear, but distant objects are blurry. It occurs when the eye grows too long or the cornea is too steeply curved, causing light to focus in front of the retina instead of directly on it.

What is the formula for MAP?

DP+ 1/3(PP) PP=SP - DP

What is the formula for cardiac output?

CO(L/min) = SV(mL/beat) * HR(beats/min)

1. What cranial nerves carry baroreceptor sensory info?

glossopharyngeal ix and vagus x

1. What neurotransmitter lowers blood pressure parasympathetically?

acytlecholine

1. What part of the brain is the control center for baroreflex (e.g., blood pressure)

medulla oblangata

1. Which positions generally increase BP?

standing up and leg crossed

Which cranial nerve controls effector response in parasympathetic baroreflex?

vagus x

What ions drive the depolarization of pacemaker cells?

ca2+ and Na+

39. What prevents summation and tetanus in cardiac muscle?

long absolute refractory period in contractile cells

1. What phase of the EKG shows atrial depolarization?

phase 1 p wave

1. What phase shows ventricular depolarization?

phase 3 qrs wave

1. What is the condition associated with a shortened ST segment?

hypercalcemia

1. What results in a flat T wave?

hypokalemia