Exam review Flashcards
Is smooth muscle voluntary or involuntary?
Involuntary
Is cardiac muscle voluntary or involuntary?
involuntary
Is skeletal muscle voluntary or involuntary?
voluntary
What is a plasmalemma, what does it fuse to, and what does are its actions?
It is the cell membrane, it fuses with tendon, and it conducts action potential, maintains pH and transports nutrients
What do satellite cells do?
They help muscle growth and development, they also respond to injury, immobilization and training
What is the sarcoplasm of the cell?
The cytoplasm of the muscle cell that stores glycogen stores and myoglobin
What do transverse (T-Tubules) do?
They carry out action potential deep into muscle fiber
What does the sarcoplasmic recticulum store?
Ca+
What do sarcomeres do and what is their stripped appearance?
They are the basic contractile element of the skeletal muscle
A bands – dark stripes (contains both actin and myosin filaments)
I bands – light stipes (contain only actin filaments)
H-zone – middle of A band (contains only myosin filaments)
M- line – middle of H zone
What is the thick filament? What is the thin filament?
The thick filament = myosin
The thin filament = actin
What are the 3 proteins actin is composed of and what are their actions?
Actin – contains myosin binding site
Tropomyosin – covers active site at rest
Troponin – anchored to actin, moves tropomyosin
What do a-motor neurons do?
They innervate muscle fibers, more operating motor units = more contractile force
What is the neuromuscular junction and what does it consist of?
Site of communication between neuron and muscle, it consist of synapse between a-motor neuron and muscle fiber
List the steps for excitation-contraction coupling.
Action potential starts in brain, arrives at axon terminals and releases ACh, Ach crosses synapse and binds to Ach receptors on plasmalemma, action potential travels down plasmalemma through the T-tubules, this triggers Ca+ release from SR, Ca+ then enables actin-myosin contraction
What does Ca+ bind to and what does it do?
Ca+ binds to troponin on the thin filament and it moves tropomyosin so that the myosin can bind to the actin and the muscle contraction can occur
During muscle relaxation what do the myofilaments look like?
they overlap
During contracted state what occurs between the filaments?
Myosin head pulls actin toward sarcomere center (power stroke), the filaments slide past each other, and all the muscle fibers shorten
What is necessary for muscle contraction?
Energy from ATP breakdown, ATP -> ADP + Pi + energy
What binds on the myosin head during muscle contraction?
ATPase
What percentage of Type 1 fiber is located in the average muscle and what is its peak tension?
50%, and its peak tension is 110 ms (slow twitch)
What percentage of Type 2 fiber is located in the average muscle and what is its peak tension?
25% - type 2a
25% - type 2x
Its peak tension is 50 ms (fast twitch)
What does fast myosin ATPase cause? What does slow myosin ATPase cause?
Fast myosin ATPase = fast contraction cycling
Slower myosin ATPase = slower contraction cycling
Which type of muscle fiber has a more highly developed SR?
Type 2, this causes faster Ca+ release
What type of muscle fiber does an endurance athlete have more of? What type of muscle fiber does a power athlete have more of?
Endurance athlete – type 1 predominate
Power athlete – type 2 predominate
Which type of muscle fiber can maintain exercise for prolonged periods and what does it require?
Type 1, it requires oxygen for ATP production
Which type of muscle fiber can run a 1,600 m run?
Type 2a
Which type of muscle fiber can run a 100 m run?
Type 2x
What does concurrent training do to type 2a and type 2x muscle fibers?
Increases type 2a and decreases type 2x
What is the recruitment order for muscle fibers?
Type 1, type 2a, type 2x
Type 1 motor units are smaller than type 2
What is concentric contraction?
Muscle shortens while producing force, maximal force decreases at higher speeds
Ex: curling a heavy weight
What is eccentric contraction?
Muscle lengthens while producing force, maximal force increases at higher speeds
Ex: lowering a heavy weight
What is static contraction?
Muscle produces force but does not change length
Ex: holding a heavy weight straight forward
What is dynamic contraction?
Muscle produces force and changes length
Ex: joint movement
Which muscle fiber motor units produces more force type 1 or type 2?
Type 2 motor units
What are substrates?
Fuel source from which we make energy
What are considered substrates?
Carbs, fats, proteins
What is the process of converting substrates into energy?
Bioenergetics
Word for all chemical reactions in the body
metabolism
How can energy release be measured?
by heat
1 calorie = heat required to raise ____________ of water from 14.5 C to 15.5 C?
1 gram
What percentages are carb and fat substrates when the body is at rest?
both at 50%
What substrate is used more in short intense workouts?
carbs
What substrate/s is used in long intermediate workouts?
carbs and fats
True or false – All carbohydrates are converted into glucose?
true
What substrate is the primary ATP for the muscle and brain?
carbs
How much carbs are stored in the body?
4.1 kcal/g ~ 2,500 kcal
True or false. Does Glycogen make ATP?
False. glycogen is converted to glucose which then produces ATP. Glucose is converted back into glycogen when not being ued
Fat amounts to how much kcal?
9.4 kcal/g ~ 70,000 kcal
True or false. Proteins are only used as back-up substrates during starvation.
True
How much protein substrate is in the body?
4.1 k/cal\
Supplies 5-10% energy for prolonged exercise
In order for protein to be used as ATP it has to be converted into one of these two things.
Glucose or FFAs (free fatty acids)
T or F. Mass action affect is when you use more of the substrate that is available than the substrates that aren’t.
True
T or F. Enzymes do not control the rate of energy production.
False
What components create ATP?
ADP + Pi + energy
What is the equation that requires the breakdown of ATP?
ATP + water + ATPase → ADP + Pi + energy
What substrate is the most accessible energy source?
Carbohydrates ( as glucose)
Fat stored as Triglycerides as to be converted into what before used to create ATP?
FFA (free Fatty Acids)
What controls the rate of metabolism and energy production?
Enzymes
What inhibits enzyme activity?
negative feedback
T or F. ATP can be created with and without oxygen.
true
Duration of ATP-PCr System?
3-15 Seconds
What does ATP- PCr System yield?
1 ATP/ 1 mol PCr
T or F. ATP- PCr system replenishes ATP during the workout?
False, replenishes ATP store during rest
What controls ATP – PCr System?
Creatine kinase
Duration of glycolytic system?
15s to 2 minutes
ATP yield of Glycolytic system?
2 to 3 mol ATP/ 1 mol substr
Rate limiting enzyme for the glycolytic system?
Phosphofructokinase
Oxidative system yields how many ATP per 1 glucose?
32 to 33
What race could be run using the oxidative system? 100 m 800m 1.5 miles 3 miles Both c and d
E
What are the three cycle of the oxidative system?
Glycolysis, krebs cycle, electron transport chain
Krebs Cycle produces a net cycle of how much?
+2 (or +3 ATP)
How much ATP per NADH?
2.5
How much ATP per FADH?
1.5
What is the major source of energy?
Triglycerides
T or F. Glucose yields 3 to 4 times more that ATP than fat.
False. fat yields more
What enters the Krebs Cycle from the glycolytic process?
Acetyl – CoA
What regulates the Krebs cycle?
Negative feedback
What system does the electrical communication belong to?
Nervous system
What system does the chemical communication belong to?
Endocrine system
What does the Endocrine System do?
Maintains homeostasis via hormones and during exercise, monitors internal environment, coordinates integration of physiological systems during rest and exercise.
What are the two groups nonsteroid hormones are divided into?
Protein/ Peptide hormones and Amino Acid-derived hor
Where are the Protein/Peptide hormones found?
Pancreas, hypothalamus, and pituitary gland
Adrenal Medulla hormones are associated with what type of group from the Nonsteriod hormones?
Amino-Acid-derived hormones
True or False: Nonsteriod Hormones are not lipid soluble and cannot cross membranes.
true
How are Hormones secreted?
They are secreted in burst (pulsatile).
Are hormones secretion negative or positive feedback and why?
Negative feedback because hormones caused changes in the body.
What is a poor indicator of hormone activity?
Plasma Concentration
The number of receptors during high plasma concentration equals Desensitization is what type of Hormone action?
Downregulation
The number of receptors during high plasma concentration equals sensitization is what type of hormone action?
Upregulation
True or False: Hormones limit scope of their effects by using hormone-specific receptors.
True
What are steroid hormones?
They are lipid soluble and can cross the membrane.
Where are the steroid hormone receptors found?
Inside the cell, in the cytoplasm or nucleus.
What does the hormone receptor complex do after it enters the nucleus?
- Its binds to DNA and regulates mRNA synthesis
What do the second messengers do for the Nonsteriod hormones?
Carry out hormone effects and strengthen the hormone signal.
What is the Prostaglandins and what do they do?
It’s the third class of (pseudo) hormones which act as local hormones in the inflammatory response and sensitize nociceptor free nerve endings.
What are important exercise related functions of the endocrine glands and their hormones?
Regulation of the metabolism and body fluids during exercise and regulate food and appetite intakes.
Major endocrine glands responsible for the metabolic regulation are?
Anterior pituitary gland, Thyroid gland, adrenal gland, and pancreas.
T or F. Pituitary gland attached to posterior hypothalamus.
False. It is attached to the inferior hypothalamus.
When the Anterior pituitary releases thyrotropin where does it travel next?
It travels to the thyroid and stimulates T3 and T4
What happens when exercise increases thyroid-stimulating hormone release?
Short term: T4 increases, prolonged exercise: T4 remains constant and T3 decreases.
What increases when the Catecholamine is released?
Heart rate, contractile force, blood pressure, Glycogenolysis, FFA, and the blood flow to the skeleton.
True or False: Insulin highers blood glucose.
False. Insulin lowers blood glucose.
True or False: Glucagon raises blood glucose.
True
What does adequate glucose require during exercise?
Glucose released by liver and uptake by muscle
What hormones increase circulating glucose?
Glucagon, Epinephrine, Norepinephrine, and cortisol
T or F. Amount of glucose released from liver depends on exercise intensity, duration.
True.
T or F. Insulin disables glucose uptake in muscle.
False. Insulin enables glucose uptake in muscle.
Where is fat stored as triglycerides?
Adipose tissue
What are lipolysis stimulated by?
Decreased insulin, Epinephrine, Norepinephrine, Cortisol, and GH.
During exercise Plasma volume causes?
Hydrostatic pressure, tissue osmotic pressure, plasma water content via sweating, blood pressure, and heart strain.
What hormones correct fluid imbalance?
Posterior pituitary gland, adrenal cortex, and kidneys.
What is the function of the adrenal cortex?
To secrete mineralocorticoids such as the aldosterone.
True or False, Osmotic water movement maximizes loss of plasma volume and maintains blood pressure.
False. It minimizes the loss of plasma volume.
The hypothalamus is the appetite control center of what organ?
The brain
What does exercise affect?
-Hunger and satiety hormones.