Use of skeletal musclesand transfer of energy
From the whole animal to the cellular level
Food energy Metabolic pool
in body
Energy storage
Internal work
External work
Thermal energy(heat)
Energy outputEnergy input
TRANSFER OF ENERGY
Calorie:The amount of heat required to raise the temperature of one gram of water from 14.5°C to 15.5°C.
1 calorie = 4.184 joules.
A good example of a structure and function relationship is skeletal muscle
Where does the ATP come from?
Explosive releaseof energy as heat
Food O 2
Energy harnessed as ATP,the common energy currencyfor the body
ATP
ATPATP
Partly used to maintainbody temperature inendotherms
Excess heateliminated to theenvironment
Muscle contraction
The body must regulate the level of ATP since you only want it around when you need it asit will break down and make heat.
Regulation of ATP production comes aboutby controlling production through graded reactionsinside cells.
The breaking of thesechemical bonds will produce heat.
The energy stored inthe chemical bonds istransferred to heat.
Glucose is broken downto make ATP
Most cells in your body.
Most ATP is produced here in the chemical reactions.
This ATP can be used to allow muscle cells to function.
Mitochondria are the power houseof the cell.
Energy within the cells used to drive the tissue- to organ- to system.
Energy transfer from food (fuel) to ATP in cells that can then be used to make proteins or used to contract muscles or to keep cells working properly by transporting itemsfor the cell (Na+ sodium & K+ potassium).
*
Explosive releaseof energy as heat
Food O 2
Energy harnessed as ATP,the common energy currencyfor the body
ATP
ATPATP
Partly used to maintainbody temperature inendotherms
Excess heateliminated to theenvironment
Muscle contraction *
Getting rid of the heat from muscle contraction and breaking chemical bonds to make the ATP
is a problem in exercise.
Many chemical reaction in our body give off heat.
A + B C
Heat
A B + C
Heat
Building a compound:
Breaking down a compound:
Snowball
Direction of arrows denotes direction of heat transfer
Liquidconvertedto gaseousvaporConvection
current
Heating pad
1 2
3 4
RadiationConductionConvectionEvaporation
Transfer heat from the hot body to cool water
For work from muscles:
Energy comes from food or body reserves (fat, protein, glycogen).
Food or body reserves provides ATP through a series of chemical reactions inside cells. (Energy transfer from chemical bonds to ATP + heat)
ATP used for muscles to function. Sliding units of muscle. (Energy transfer from muscles to external work + heat)
Muscle fatigue: This is a study of human performance.
Task dependant (type of muscle)
Before we can study this one has to know how nerves andmuscles work for performing a task
Muscle fatigue: This is a study of human performance.
Task dependant (type of muscle)
Before we can study this one has to know how nerves andmuscles work for performing a task
nerve
muscle
Muscle fibers
Axon terminals
Terminal button
Chemically-gated ion channel forNa+, K+, or Cl2
Presynaptic axonterminal
Synaptic knob
Synaptic vesicle
Postsynaptic neuronReceptor for neurotransmitter
Synaptic cleft
Ca2+
Voltage-gatedCa2+ channel
Neurotransmitter molecule
Subsynaptic membrane
Muscle
muscle
Neurotransmitter
Na+
K+
Ion movement results in electrical change across cell membrane
Receptor on cell
Muscle cell
2 K+
3 Na+
ATP
Pump ions back acrossmembrane (needs ATP)
Action potentialpropagationin muscle fiber
Axon of motor neuronMyelin sheath
Terminal buttonAxon terminal
Vesicle of acetylcholine
Acetylcholine receptor site
Acetylcholinesterase
Plasma membraneof muscle fiber
Voltage-gated Na+ channel
Chemically gated cation channel
Contractile elements within muscle fiber
Motor end plate
K+
Na+
Ca2+
Na+
Voltage-gatedcalcium channel
Action potentialpropagationin motor neuron
Electrical change results in a process within the cell tocause the muscle to contract.(calcium ion movement)
Ca2+ is pumped backTakes ATP
To increase muscle contraction:1. Increase muscle cell activity
(increase nerve activityby # of electrical events)
2. Increase the # of muscle units(increase # of nerves used)
Need fine control:Pick up a piece of paper or a rock.
Muscle fatigue:
nerve
muscle
1. The nerve
2. At the nerve to muscle
3. At the muscle level
Muscle fatigue:
nerve
muscle
1. The nerve
2. At the nerve to muscle
3. At the muscle level
ATP needed here to keep ions (Na+ & K+) normal
ATP needed here to keep vesicles cycling
ATP needed here to keep muscle working
Note: ATP is made inside the cells that require it.
• Grip strength 1st-1 second series of contractions- measure the time it takes to fatigue 50%- graph each others data- discussion of results
1. measures of forearm circumference and relate to time (muscle mass, bone
thickness- distorts results)2. did they just eat, tired, sleep, etc..(could have a box to check off on chart)
Name Time to 50% Forearm (cm) Tired, food, etc Other factors
• Pinch strength– Same idea as the grip strength– Can graph on same graph (left and right
sides)
Name Right arm 50%
Left Arm 50%
RightFinger 50%
LeftFinger 50%
Tired, food, etc
Other factors
Heart rate changes:
Decrease HR- decrease breathing rate just sitting still (not to slow that you pass out)- cold rag on back of the neck (not on face - some people
have strong diving responses and can pass out. KIDS !!!) Increase HR
- increase breathing rate just sitting still (not to fast that you pass out)- measure before and after running in place (5 min)
Graph data with variable used. Compare with class and have discussion.
- Reasons for the changes.- Reasons for differences in students for same test.- List what other types of experiments could be done.
Why does HR go up or down?
• Oxygen to tissues for making ATP for the muscles to work.
• How does oxygen get to the tissues?
• Heart is a pump for blood. The blood carries the oxygen. So HR goes up to bring the blood with its oxygen to the muscle.
Heartpumpsthe blood
Acknowledgements
Robin Cooper(UK- Biology)
Terry Williams (UK- Biology, Secondary science Ed.)
Richard Cooper (6th- Morton Middle)
Ann Cooper (10th- Lafayette High, past Morton student)
Jan. 2007
Folder: Human Physiology with Vernier Inside folder find----
17a Grip Strength Fatigue
Note: do not hold on to hand grip place when conducting finger fatigue experiment.
Hand Grip
Finger Grip
Find program: 27 Heart Rate & Fitness
Note: Watch the direction of arrows on hand device and monitor.Need to be in the same direction and keep handsbetween the monitor.
1st page should look like this
NAME OF PROGRAM: 27 Heart Rate & Fitness
1sec hand grip contractionsDo it for 30 sec to match 50% fatigue
To copy pictures: Go to “select all” and then “copy” and “paste”
Can be put directly into ppt or any graphic program