Midterm 1

Question 1

What is a Homeostatic response

Answer 1

a body RESPONSE to get back to a resting or steady state

Question 2

Is getting hot while you exercise a homeostatic or allostatic response

Answer 2

homeostatic; it is a response

Question 3

What is a Allostatic resopnse

Answer 3

an ANTICIPATORY reaction to an activity

Question 4

Is heart rate increasing before exercise a homeostatic or allostatic response

Answer 4

allostatic; it is an anticipation

Question 5

What is the function of the Cerebral Cortex?

Answer 5

-Language
- reasoning and abstract thinking
- sensory and voluntary motor control

Question 6

What is the function of the Basal Ganglia

Answer 6

• initiates and controls movements
• makes movement efficient
• cognitive, emotions and movements
• addiction and dopamine

Question 7

What’s the function of the Hypothalamus

Answer 7

-metabolism and temperature
- cardio vascular/respiratory rhythm (ans)
-sleep

Question 8

What’s the main functions of the limbic system

Answer 8

-processing and interpreting sensory info
- neurotransmitters release
-better mood and pain
-motivation
- stress

Question 9

What parts makes up the brain stem

Answer 9

-midbrain
-pons
-medulla oblongata

Question 10

What is the function of the brain stem

Answer 10

• connect neurons to spinal cord
• nuclei have cardiac and respiratory functions (thermoregulation)
  -reduces vagal tone
  -symp nerve activation

Question 10

What is the function of the cerebellum

Answer 10

-body posture and equilibrium
-receives sensory info from afferents
- sends info to thalamus (then cerebral cortex)

Question 11

What is the difference between efferent and afferent nerves

Answer 11

-Efferent> Motor
- Afferent> Sensory

Question 12

What is an Interneurons role?

Answer 12

middle man to connect sensory and motor neurons

Question 12

What ratio contributes to variation in motor skills?

Answer 12

Motor Neuron-Muscle fiber ratio

Question 13

What is the All or None Principle?

Answer 13

all the muscle fibers innervated in a motor neuron are simulated to contract

Question 14

What is the Motor Unit Size Principle?

Answer 14

there is an anatomic basis that determines the order of motor units to produce smooth muscle action

Question 15

What’s an Action Potiential?

Answer 15

-wave of depolarization
- made by changes in membrane potential

Question 16

What are the 3 Action Potential Stages

Answer 16

• Depolarization (Na+ entering)
• Repolarization (K+ leaving)
• Ions returning with Na+/ K+ pumps

Question 17

What do Nodes of Ranvier do?

Answer 17

-ion diffusion in and out of neuron

Question 18

What do Myelin Sheaths do?

Answer 18

• protect axons
• faster node transmissions

Question 19

Explain how skeletal muscle contracts

Answer 19

1. Vesicles in terminal axon release ACh > attach to receptors in sarcolemma
2. Receptor depolarizes > t-tuble causes Ca release
3. Ca binds to troponin-tropomyosin in actin> inhibition of actin with myosin
4. Actin+myosin ATPase makes ATP to produce crossbridge movement
5. muscle shortens, bond breaks, sliding filaments
6. when Ca is high crossbridge is activated, Ca moves back, everything moves back

Question 20

What order do muscle fibres innervate?

Answer 20

I > IIa > IIx

Question 21

Explain the characteristics of Type I fibres

Answer 21

-Slow
- Low Force
- Slow cotract speed
-high fatigue resistance
-no sag
- Slow Oxidative fibre

Question 22

Explain the characteristics of Type IIa fibres

Answer 22

• Fast- fvatigue resistant
• moderate force
• fast contraction
• moderate fatigue resitance
  -yes sag
• fast oxidative glycotic

Question 23

Explain the characteristics of type IIx fibres

Answer 23

- Fast Fatigable - High force -fast contraction - low fatigue resistance -yes sag -fast glycolytic

Question 24

What is Motor Unit Recruitment

Answer 24

Increasing the number of motor units recruited

Question 25

What is Motor unit rate coding

Answer 25

Increasing the frequency of motor unit discharge

Question 26

What do muscle spindles do

Answer 26

- responds to any stretch of muscle - provides info about changes in fibre length and tension - increase the level of muscle contraction

Question 27

What do nuclear bag fibers do

Answer 27

- in muscle spindles - respond to phasic stretch

Question 28

what do nuclear chain fibers do

Answer 28

- in muscle spindles - respond to static stretch

Question 29

What do golgi tendon organs do

Answer 29

- respond to tension from CONTRACTION - protective mechanism (sensory) - reduces level of muscle contraction

Question 30

Explain the stretch/ myotatic reflex

Answer 30

- involuntary contraction from fast muscle stretch -reflex arc> two nerves and one synapse - helps to maintain body balance - happens even when standing still

Question 31

what is the shape of the length-tension curve

Answer 31

exponential

Question 32

What determines the length tension curve

Answer 32

- number of cross bridge formations - enviromental conditions (pH, ATP, Ca)

Question 33

What makes an isometric contraction

Answer 33

amount of overlap depend on length of muscle before activation

Question 34

What makes a shortening contraction

Answer 34

sliding movement makes myosin be overlapped by actin

Question 35

what makes a lengthening contraction

Answer 35

crossbridge has less tension than stretching force. actin and sarcomeres are pulled away from each other

Question 36

Explain the Popping Sarcomere Hypothesis

Answer 36

-extension of individual half-sarcomeres -weakest to strongest - sarcomere stretched until passive tension can support the tension and sarcomere is popped

Question 37

Why do we experience muscle soreness

Answer 37

- group iii fibers (afferents) respond to deformation and intramuscle substance which cause pain -they project to the CNS and promote pain and muscle soreness

Question 38

What is the shape of the force-velocity curve

Answer 38

Hyperbolic

Question 39

what is the shape of the power curve

Answer 39

Parabolic

Question 40

What's the role of velocity and force in power production

Answer 40

- force and velocity are inverse -increase in muscle shortening(V) causes force to decrease -isometric (0 V) there is max force

Question 41

What is optimum force and velocity

Answer 41

P=F*V around below 50% of max values for each

Question 42

T/F: sarcomere in series and in parellel produce the same work, power potential and force

Answer 42

False. They only produce the same work and power potential.

Question 43

What are the advantages of sarcomeres in series vs in parallel

Answer 43

Parallel: force production Series: Velocity and Displacement

Question 44

Whats the difference between Anatomical (ACSA) cross section area and Physiological (PCSA) cross section area

Answer 44

ACSA: largest cross sectional area along the length of the muscle PCSA: total cross section area of all fibers with a muscle

Question 45

What are the 3 training principles

Answer 45

- Individuality - Specificty - Reversibility

Question 46

What is exercise volume

Answer 46

the amount of work done in a workout

Question 47

What is the progressive loading principle

Answer 47

the workout gets more difficult over time

Question 48

What are the results of progressive overloading in different populations

Answer 48

- limited progress in elite weight lifters - any method with work in untrained individuals - adaptations are limited in clinical populations

Question 49

In resistance training, changes in muscle strength and power is due to:

Answer 49

-neural adaptations -muscle hypertrophy

Question 50

in untrained individuals, the influence of strength training can be seen as an increase in _____ to muscles. It is then followed by increase in ________, and this ______ effect may be more pronounced in _____ fibres

Answer 50

- neural activation - Muscle fibre size - hypertrophic - fast twitch

Question 51

Explain Neural Control of Strenght Gain

Answer 51

- greater # of motor units will activate at a time - rest>sub max>MVC before training> MVC after training - reduce of contract inhibition in golgi - inhibit antagonist increases agonist

Question 52

What is cross education

Answer 52

an increase in strength is witnessed within an untrained limb following unilateral strength training in the opposite, contralateral limb

Question 53

What mechanisms determine cross education

Answer 53

increase of central motor output to the muscle