EXPH 2045 Exam 1 - Homeostasis/Skeletal

________ energy is the minimum amount of energy that is required for a chemical reaction to begin. A. Differentiated B. Generated C. Neutral D. Activation

D. Activation

In a reversible reaction, when the rate of product formation is equal to the rate of reactant formation, the reaction is ______________. A. A net decomposition reaction B. Stopped C. In danger of exploding D. At equilibrium E. A net synthesis reaction

D. At equilibrium

A substance that will increase the rate of a chemical reaction without being permanently changed is called a/an __________. A. Reducing agent B. Solute C. Oxidator D. Catalyst

D. Catalyst

Which of the following is NOT a function of the control center within a feedback mechanism? A. Receives and processes information B. Controls effectors C. Establishes a set point D. Detects a change in the value of the variable

D. Detects a change in the value of the variable

Which of the following is incorrect regarding how intracellular acidosis contributes to peripheral (in the muscle) fatigue? A. Decreases the force of the cross-bridge by inhibiting the weakly-to strongly bound step B. Decreases the shortening velocity of the cross-bridge by inhibiting the release of ADP C. Decreases the sensitivity of the myofilaments to calcium D. Increases the force of the cross-bridge by inducing an unconventional power stroke where myosin and actin do not complete the full cycle

D. Increases the force of the cross-bridge by inducing an unconventional power stroke where myosin and actin do not complete the full cycle

An eccentric contraction when A. The action potential frequency is high enough that no relaxation of muscle fibers occurs B. A muscle produces constant tension during contraction C. A muscle produces an increasing tension during contraction D. A muscle produces increasing tension as it shortens E. A muscle is lengthened while it is activated

E. A muscle is lengthened while it is activated

The presence of water in our bodies allows us to ________ A. Cool the body with sweat B. Maintain a constant body temp C. Provide an environment for chemical reactions D. Keep tissues moist and reduce friction E. All the above

E. All the above

Which of the following factors will influence the rate of a chemical reaction? A. Temperature B. Concentration of reactants C. Presence of catalysts D. Presence of enzymes E. All the above F. None of the above

E. All the above

Which of the following is correct about the energetic demand of muscle contractions? A. Muscle contractions are very efficient and do not require a lot of energy (ATP) B. At the start of a muscle contraction, ATP is synthesized by all four metabolic pathways in a sequence where oxidative phosphorylation does not contribute to ATP synthesis until after 2 minutes of muscle contraction C. Eccentric contractions require the most ATP because they can generate the most force D. Isometric contractions require the most ATP because they have a lot of cross-bridges simultaneously bound in the strongly bound state E. Concentric contractions require the most ATP because the shortening of the muscle increases the rate that the cross-bridges go through their cycle

E. Concentric contractions require the most ATP because the shortening of the muscle increases the rate that the cross-bridges go through their cycle

Our lungs inhale air, drawing in O2, and exhale air, expelling CO2. Both molecules are small and nonpolar and freely pass through the membrane bilayers of cells in the lung. The movement of O2 from the lungs into the bloodstream is an example of _________. A. Active transport B. Facilitated diffusion C. Osmosis D. Vesicular transport E. Diffusion

E. Diffusion

cytoskeleton

system of microtubules and microfilaments that gives cells support, shape, movement

centrioles

used in formation of microtubules found in cilia and flagella

lysosomes

vesicles that contain digestive enzymes

cilia

move materials over the surface of the cells

Match the level of organization of the body with the major characteristics of each level: Chemical Level, Cellular Level, Tissue Level, Organ Level, Organ System Level, Organism Level A. Different organs combine to make up a system B. Atoms combine to form molecules C. Organ systems combine to make up this level D. Molecules form organelles E. Similar cells and surrounding materials F. Different tissues combine to form this level

-Chemical Level: B. Atoms combine to form molecules Cellular Level: D. Molecules form organelles -Tissue Level: E. Similar cells and surrounding materials -Organ Level: F. Different tissues combine to form this level -Organ System Level: A. Different organs combine to make up a system -Organism Level: C. Organ systems combine to make up this level

What is tropomyosin? A. A protein found along actin that blocks the active myosin binding sites B. A T tubule and 2 adjacent terminal cisternae C. The combination of myosin heads with active sites on actin molecules D. The movement of myosin head while attached to actin myofilament E. After exercise, the O2 taken in that exceeds the O2 required for resting metabolism

A. A protein found along actin that blocks the active myosin binding sites

As you are lifting a box, someone places an extra weight on top of it. For your muscle to continue contracting and lifting the box, the muscle must A. Activate more muscle fibers by recruiting additional motor units B. Lower its threshold C. Reduce its wave summation D. Shift from isometric to isotonic contraction E. Shift from slow-twitch to fast-twitch mode

A. Activate more muscle fibers by recruiting additional motor units

Aldosterone is a hormone that increases the level of Na+ in the blood. Considering negative-feedback regulation of blood Na+ levels, which of the following events would most likely be an effect of aldosterone on the body if blood Na+ levels decreased? A. Aldosterone would cause a decrease in the amount of Na+ that was excreted out of the body via urine. B. Aldosterone would cause an increase in the amount of Na+ that was excreted out of the body via urine. C. Aldosterone would reduce the activity in the brain that stimulated salty food cravings D. Aldosterone would decrease the amount of Na+ that is absorbed by the small intestine and transported into the blood.

A. Aldosterone would cause a decrease in the amount of Na+ that was excreted out of the body via urine.

All the synthesis reactions in the body are called _________. A. Anabolism B. Hydrolysis C. Dissociation D. Catabolism E. Oxidation-reduction

A. Anabolism

Smooth muscle and cardiac muscle are similar in that they both ______ A. Are under involuntary control B. Are striated C. Are widely distributed in the body D. Have multiple nuclei E. Are under voluntary control

A. Are under involuntary control

Cancer cells are often associated with losing the ability to attach to neighboring cells. Which of these protein types might cancer cells stop producing? A. Cadherins B. G protein complexes C. Nuclear proteins D. Channel proteins

A. Cadherins

Enzymes are proteins that increase the rate of chemical reactions by ______. A. Decreasing the activation energy of a reaction B. Increasing the concentration of the reactants C. Increasing the activation energy of the reaction D. Adjusting the temperature of the reaction

A. Decreasing the activation energy of a reaction

Which of the following is not an important function of calcium ions in skeletal muscle activity? A. Depolarizations of the sarcolemma B. Initiating release of ACh from the presynaptic terminal C. Exposure of the active myosin binding sites on actin D. All of these are important functions of calcium ions in skeletal muscle contraction

A. Depolarizations of the sarcolemma

T or F: A. The pH scale is a measure of O2 concentration in a solution B. The pH scale indicates the concentration of H+ in a solution C. The pH scale ranges from 0-14 D. Neutral solutions have a pH of 7 E. Solutions with a pH greater than 7 are acidic F. Solutions with a pH greater than 7 are basic

A. False B. True C. True D. True E. False F. True

The electrical properties of cells are the result of _______ A. Ion concentration differences across the plasma membrane B. Receptor sites that are present on the plasma membrane C. Phosphorylation reaction within the cytoplasm D. Phospholipids in the plasma membrane E. None of the above

A. Ion concentration differences across the plasma membrane

Blood glucose concentration rises after a meal and stimulates the pancreas to release the hormone insulin. Insulin travels in the blood and stimulates the uptake of glucose by body cells from the bloodstream, thus reducing blood glucose concentration. This is an example of________. A. Negative feedback B. Positive feedback C. Dynamic equilibrium D. Integration control E. Set point adjustment

A. Negative feedback

The sarcoplasmic reticulum A. Stores Ca2+ B. Shortens during muscle contraction C. Transmits nerve impulses to the myofibrils D. Connects adjacent sarcomeres E. Covers the muscle fiber

A. Stores Ca2+

Which of the following descriptions best represents the appearance of the sarcomere during peak contraction? A. The H zone is eliminated, and the I bands are very thin B. The width of the A band is slightly less than width of the I band. C. The H zone is equivalent to one-third of the length of the A band D. The I band and A bands are of equal widths

A. The H zone is eliminated, and the I bands are very thin

Complete or fused tetanus of muscles is when A. The action potential frequency is high enough that no relaxation of muscle fibers occurs B. A muscle produces varying amounts of tension during contraction C. A muscle produces less tension as the velocity of shortening increases D. A muscle produces more tension as the velocity of shortening increases E. A muscle produces tension, but the length of the muscle is increasing

A. The action potential frequency is high enough that no relaxation of muscle fibers occurs

Which of the following does not accurately describe factors that determine the amount of force generated during a muscle contraction? A. The number of cross-bridges that can form is higher in a short muscle fiber compared with longer fibers B. Muscle fibers that have larger diameters have more myofibrils and therefore can form more cross-bridges in parallel C. Increasing the stimulation frequency of a muscle fiber results in increased calcium release and formation of more cross bridges. D. Muscle fibers that are placed in their optimal sarcomere spacing will maximize the number of cross-bridges that can form.

A. The number of cross-bridges that can form is higher in a short muscle fiber compared with longer fibers

Why does muscle activity affect the temperature of the body? A. The rate if chemical reaction increases in muscle fibers during contraction, and the muscle is not 100% efficient in converting chemical into mechanical energy so the rate of heat production also increases B. Muscle contraction generates pyrogens which rest the body's internal thermostat to a higher temperature C. Muscle activity directs more warm blood to the muscle away from the central core causing a cooling effect on your internal organs D. Increased muscle activity causes a rise in adipose stores which increases the insulation value of the body

A. The rate if chemical reaction increases in muscle fibers during contraction, and the muscle is not 100% efficient in converting chemical into mechanical energy so the rate of heat production also increases

The primary structure of a protein is __________. A. The sequence of amino acids in the polypeptide chain B. The folded, helical nature of the molecule C. Represented by multiple polypeptide chains D. They hydrogen bonds between amino acids E. The number of polypeptide chains in the molecule

A. The sequence of amino acids in the polypeptide chain

Due to the pattern of innervation of skeletal muscle, one would expect that A. There are fewer motor neurons than skeletal muscle fibers B. There are fewer muscle fibers than motor neurons C. The number of muscle fibers and motor neurons is equal

A. There are fewer motor neurons than skeletal muscle fibers

Which of the following statements concerning fast-twitch muscle fibers is true? A. They hydrolyze ATP rapidly due to their high ATPase activity B. They have large deposits of myoglobin C. They preferentially rely on aerobic respiration for ATP synthesis D. They have a well-developed blood supply E. They have many mitochondria

A. They hydrolyze ATP rapidly due to their high ATPase activity

Arrange the following list in the correct sequence: (1) An action potential is conducted deep into the muscle fiber by the T tubule (2) Ca2+ ions bind to troponin (3) Voltage sensitive receptors (DHPR) initiate the release of Ca2+ through channels (RYR) in the sarcoplasmic reticulum (4) Ca2+ diffuses into the sarcoplasm (5) The troponin-tropomyosin complex moves exposing active sites. A. 1,5,2,3,4 B. 1,3,4,2,5 C. 1,2,3,4,5 D. 1,3,2,5,4 E. 1,4,3,2,5

B. 1, 3, 4, 2, 5

What is a triad? A. A protein found along the groove of the actin thin filament B. A T-tubule and two adjacent termina cisternae C. The combination of myosin heads with active sites on actin molecules D. The movement of myosin head while attached to actin myofilament E. After exercise the O2 taken in that exceeds the O2 required for resting membrane metabolism

B. A T-tubule and two adjacent termina cisternae

The active sites to which cross-bridges attach are found on the _______ A. Sarcoplasmic reticulum B. Actin myofilaments C. Z disks D. T tubules E. Myosin myofilaments

B. Actin myofilaments

A researcher discovered a sensory receptor that detects decreasing oxygen concentrations in the blood. According to the principle of negative feedback, it is likely that stimulation of this sensory receptor will produce which of the following types of responses? A. A decrease in heart rate B. An increase in the respiratory rate C. An increase in physical activity D. Unconsciousness E. Both a decrease in heart rate and an increase in the respiratory rate will occur

B. An increase in the respiratory rate

Which of the following statements regarding the sliding filament model is false? A. Actin and myosin do not shorten during contraction B. Both actin and myosin myofilaments shorten during contraction C. The sarcomere shortens D. The I band and H zones become narrower during contraction E. The A band remains in constant length

B. Both actin and myosin myofilaments shorten during contraction

Chemicals that prevent large changes in pH values when either acids or bases are added are called ________. A. Neutrality factors B. Buffers C. Alkalinity factors D. Ions

B. Buffers

Lack of Acetylcholine esterase in the synaptic cleft would result in A. A decrease in Ach production by the motor neurons B. Continuous stimulation of the postsynaptic membrane C. Rapid degradation of acetylcholine D. Relaxation of the muscle E. Continuous stimulation of the presynaptic terminal of the motor neuron

B. Continuous stimulation of the postsynaptic membrane

A drug that blocks the active transport of Ca2+ from the sarcoplasm back into the sarcoplasmic reticulum would result in A. Relaxation of the muscle fiber B. Contraction to continue and an inability to relax the muscle C. Muscle hypertrophy D. Fibrosis of the muscle E. An imbalance of blood calcium

B. Contraction to continue and an inability to relax the muscle

Sucrose is formed when the simple sugars fructose and glucose are covalently bonded. This reaction releases water. What type of reaction is this? A. Hydrolysis B. Dehydration C. Monomeric D. Catabolic

B. Dehydration

In the reversible reaction, CO2 + H2O <----> H2CO3 <----> H+ + HCO3-, an increase in respiration rate will decrease the concentration of CO2 in the blood. What will this do to the amount H+ in the blood? A. H+ will be unchanged B. H+ will decrease C. H+ will increase D. H+ will first increase then decrease

B. H+ will decrease

Which of the following helps explain the increased tension seen in multiple wave summation? A. Increased motor unit recruitment B. Increased concentration of Ca2+ around the myofibrils C. Exposure of more active sites on myosin myofilaments D. The breakdown of elastic elements in the cell E. Decreased stimulus frequency

B. Increased concentration of Ca2+ around the myofibrils

In excitation-contraction coupling, A. Ca2+ must bind with myosin to expose active sites on actin B. Myosin heads bind to exposed active sites on actin C. Cross-bridges form between myosin heads and Ca2+ D. Movement of the troponin-tropomyosin complex causes actin myofilaments to slide. E. ATP binds to actin myofilaments

B. Myosin heads bind to exposed active sites on actin

When a woman is giving birth, the head of the baby pushes against her cervix and stimulates the release of the hormone oxytocin. Oxytocin travels in the blood and stimulates the uterus to contract. Labor contractions become more and more intense until the baby is delivered. This is an example of ___________. A. Negative feedback B. Positive feedback C. Dynamic equilibrium D. Integration control E. Set point adjustment

B. Postive feedback

Which organ system of blood cell production? A. Cardiovascular B. Skeletal C. Digestive D. Nervous E. Endocrine

B. Skeletal

Glycogen is the _________ A. Major macronutrient for most cells in the human body B. Storage of carbs in animals C. Storage of carbs in plants D. Nondigestible plant polysaccharide E. Sugar found in RNA

B. Storage of carbs in animals

The plasma membrane of an excitable cell is more permeable to K+ because A. Of its + electrical charge B. There are more leak ion channels for K+ than Na+ C. Protein molecules cannot exit through the plasma membrane D. Calcium ions block Na+ and Cl- channels E. There are more gated channels for K+

B. There are more leak ion channels for K+ than Na+

Synaptic vesicles in the neuromuscular junction contain ___________ A. Calcium B. ATP C. Acetylcholine D. Acetylcholinesterase E. Sodium

C. Acetylcholine

During the contraction phase of a muscle twitch, A. ACh is released via exocytosis into the synaptic cleft B. Na+ diffuses into the muscle fiber C. Actin-myosin cross-bridges form D. Ca2+ ions are transported back into the sarcoplasmic reticulum E. The action potential propagates down the T tubule

C. Actin-myosin cross-bridges form

Which of the following is correct regarding how elevated inorganic phosphate (Pi) contributes to peripheral (in the muscle) fatigue? A. Increases the amount of calcium released from the sarcoplasmic reticulum B. Increases the sensitivity of the myofilaments to calcium C. Decreases the force of the cross-bridge by inducing an unconventional power stroke where myosin and actin do not complete the full cycle D. Decreases the shortening velocity of the cross-bridge by inhibiting the release of ADP

C. Decreases the force of the cross-bridge by inducing an unconventional power stroke where myosin and actin do not complete the full cycle

When the hydrogen bonds that maintain a protein's three-dimensional shape are broken, the protein becomes nonfunctional, and is said to be _________. A. Essential B. Saturated C. Denatured D. Structural E. Unsaturated

C. Denatured

ATPase is found in A. Ryanodine receptors on the sarcoplasmic reticulum B. Thin actin myofilaments C. Myosin heads D. Tropomyosin grooves E. Troponin molecules

C. Myosin heads

Which of the following is true? A. Sarcomere spacing and myosin and actin overlap are not important to tension generation because the skeletal muscle system has adapted to generate peak tension in all positions. B. Overstretching a muscle will increase its active tension C. Optimal actin and myosin overlap will produce maximal active force during contraction D. The greatest amount of tension is achieved when actin and myosin do not overlap E. Tension is the greatest when the sarcomere is compressed, there is minimal room left in the H-zone and the z-discs are close to myosin

C. Optimal actin and myosin overlap will produce maximal active force during contraction

For muscle relaxation to occur, A. Ca2+ must be transported to troponin B. Ca2+ must be released from the sarcoplasmic reticulum C. The active sites on actin must be blocked by tropomyosin D. Na+ must be actively transported to troponin E. The active sites on myosin must be uncovered

C. The active sites on actin must be blocked by tropomyosin

What is a cross-bridge? A. A protein found along the groove of the F-actin double helix B. A T tubule and two adjacent terminal cisternae C. The combination of myosin heads bound to the active sites on actin molecules D. Only the movement portion when the myosin head pivots in the light chain domain while attached to the actin myofilament E. After exercise, the O2 taken in that exceeds the O2 required for resting metabolism

C. The combination of myosin heads bound to the active sites on actin molecules

Which of the following is true about the force-frequency relationship of fast-twitch compared with slow-twitch muscle fibers? A. The different types do not alter the force frequency relationship of the muscle B. The slower twitch response of fast fibers requires higher frequencies to achieve peak force production C. The faster twitch response of fast fibers requires higher firing frequencies to achieve peak force production D. The force-frequency relationship is shifted to the left in fast-twitch fibers indicating lower firing frequencies are required to achieve peak force production E. The faster twitch response of slow fibers requires lower firing frequencies to achieve peak force production

C. The faster twitch response of fast fibers requires higher firing frequencies to achieve peak force production

Kinetic energy is ________. A. Energy that moves in waves B. Stored energy that could do work but is not doing so C. The form of energy that does work D. Movement of ions or electrons E. Energy that flows between objects with different temperatures

C. The form of energy that does work

Which of the following is incorrect about the performance-duration relationship of muscle contractions? A. Low-intensity muscle contractions (low force and/or power) can be sustained for long-durations (>5 minutes) and use primarily aerobic metabolism for ATP synthesis B. High-intensity muscle contractions (high force and/or power) can only be sustained for seconds to a few minutes and use primary glycolysis and the creatine kinase reaction for ATP synthesis C. The intensity of the muscle contraction does not influence the duration that the contraction can be sustained D. The relationship between the intensity of the muscle contraction and duration that it can be sustained is non-linear and best described by exponential function

C. The intensity of the muscle contraction does not influence the duration that the contraction can be sustained

Which of the following is NOT a property of the myosin head? A. They form cross-bridges with the active sites on the actin B. They have a hinge region in the light chain domain that allows them to pivot ~70 degrees C. They bind to troponin D. They have ATPase to hydrolyze ATP they bind and hydrolyze ATP per cross-bridge cycle

C. They bind to troponin

A symporter will transport ______ across the cell membrane. A. Two different ions or molecules in opposite directions B. Two of the same ions or molecules in opposite directions C. Two different ions or molecules in the same direction D. One specific ion or molecule Two of the same ions or molecules in the same direction

C. Two different ions or molecules in the same direction

Clostridium botulinum is a bacterium that produces a potent neurotoxin called botulinum toxin (Botox), which blocks the release of Ach. What influence would an intramuscular injection of Botox have on the ability to activate the muscle? A. No influence because ACh is not important for muscle contraction B. High-force muscle contractions because Ach will be stuck in the synaptic cleft C. Muscle cramps D. Muscle paralysis because of the inability to activate the muscle E. All the above F. None of the above

D. Muscle paralysis because of the inability to activate the muscle

If all the calcium within a muscle fiber was removed but ATP was still present, which of the following could still occur? A. The myosin heads would reach up and bind to actin to form a cross-bridge B. The troponin molecules on the actin thin filament would change shape, causing tropomyosin to move and expose myosin binding sites C. Myosin heads would transition from weakly-to strongly bound and initiate the power stroke D. Myosin heads would unbind from actin and return to their resting position

D. Myosin heads would unbind from actin and return to their resting position

Which of the following is true about the resting membrane potential? A. Sodium ion concentration is greater inside the cell B. Negatively charged proteins are more concentrated outside the cell C. A greater concentration of calcium ions ins found in the cytoplasm inside the cell D. Potassium ion concentration is greater inside the cell E. None are what occurs during RMP

D. Potassium ion concentration is greater inside the cell

The repolarization phase of the action potential is primarily due to ______ A. Voltage gated Na+ channels opening B. Rapid diffusion of Na+ into the cell C. Rapid diffusion of Ca2+ out of the cell D. Rapid diffusion of K+ out of the cell E. The Na+/K+ pump increasing activity

D. Rapid diffusion of K+ out of the cell

Each presynaptic terminal contains ____________ which contain the neurotransmitter ___________ that, when released, cause ligand-gated Na+ channels to open in the motor end plate. This causes _____________ in the muscle cell. A. Acetylcholine receptors; acetylcholine; repolarization B. Proteins; acetylcholine; repolarization C. Mitochondria; acetylcholinesterase; depolarization D. Synaptic vesicles; ACh; depolarization

D. Synaptic vesicles; ACh; depolarization

Indicate which statement is not an accurate representation of the relationship between structure (anatomy) and function (physiology) A. The convoluted tubules of the kidneys allow for filtration of the blood B. A bone's mineralized outer structure allows it to provide support to the musculature C. The shape of the lungs allows for ease of expansion with the intake of air D. The spine of the scapula is a bony ridge on the posterior scapular surface

D. The spine of the scapula is a bony ridge on the posterior scapular surface

Which of the following statements about slow-twitch oxidative muscle fibers (MHC I) is false? A. They hydrolyze ATP slowly B. They have a well-developed blood supply (high number of capillaries) C. They have large amounts of myoglobin D. They have high glycolytic capacity E. None of the above are false

D. They have high glycolytic capacity

Which of the following is a synthesis reaction? A. Sucrose is chemical separated to form one molecule of glucose and one molecule of fructose B. ATP is converted to ADP C. Sodium chloride is dissolved in water D. Two amino acids are bonded together to form a dipeptide E. Several dipeptides' chains are formed from digestion of a long polypeptide chain.

D. Two amino acids are bonded together to form a dipeptide

Which of the following is most consistent with homeostasis? A. As blood pressure fails, blood flow to cardiac muscle decreases B. As the mean BP gradually increases in aging people, the blood vessel walls become thinner C. Men working in a hot environment drink large quantity of water, and their urine volume increases D. As the body temperature decreases, blood vessels in the periphery dilate E. Elevated blood glucose levels cause insulin secretion to increase, which in turn causes cells to take up glucose

E. Elevated blood glucose levels cause insulin secretion to increase, which in turn causes cells to take up glucose

Which is the following being incorrect regarding muscle fatigue (fatiguability)? A. It is an acute reduction in force or power that occurs in response to repeated muscle contractions B. It is reversible by periods of rest C. It can occur before an observable loss in muscle force or power (performance) D. It can occur from factors originating within the muscle (peripheral fatigue) or within the nervous system (central fatigue) E. It is the subjective sensation of being tired and lethargic

E. It is the subjective sensation of being tired and lethargic

The neurotransmitter acetylcholine, released at the neuromuscular junction increases permeability of the muscle cell membrane to ____________ A. Choline B. Inorganic phosphate C. Calcium ions D. Potassium ions E. Sodium ions (Na+)

E. Sodium ions (Na+)

Which system removes nitrogenous waste from the blood and regulates blood pH, ion balance, and water balance? A. Respiratory B. Lymphatic C. Cardiovascular D. Immune E. Urinary

E. Urinary

During a muscle fiber contraction, which of the following decreases in size? A. A band B. Entire sarcomere C. H zone D. I band

Entire sarcomere, H zone, I band

T or F? Positive-feedback mechanisms are always damaging to the body.

False

Which of the following are ATPases that hydrolyze ATP during muscle contraction? A. Myofibrillar - ATPase B. Troponin - ATPase C. Tropomyosin- ATPase D. Titin- ATPase E. Sarcoendoplasmic reticulum Ca2+ ATPase (SERCA pump) F. Na+/K+ - ATPase (pump)

Myofibrillar - ATPase, Sarcoendoplasmic reticulum Ca2+ ATPase (SERCA pump), Na+/K+ - ATPase (pump)

T or F? The control center compares input from a receptor with the ideal normal value for a condition called a set point.

True

rough endoplasmic reticulum

extensive membrane system upon which protein synthesis takes place

microvilli

increase surface area of the pm for absorption of substance

nucleus

largest organelle of the cell; contains DNA

mitochondria

major sites of ATP synthesis by the process of respiration

flagella

propels spermatozoa in humans

Golgi apparatus

stacks of flattened membranes; modifies, packages, and distributes proteins and lipids

ribosomes

structures upon which protein synthesis directly takes place

plasma membrane

the outer boundary of cells; controls the entry and exit of substances