Oxford University Press | Online Resource Centre

Question 01

The two principal contractile proteins found in skeletal muscle are:

a) actin and troponin

b) actin and myosin

c) troponin and tropomyosin

d) myosin and tropomyosin

e) actin and tropomyosin

Question 02

The sarcoplasmic reticulum in muscle cells acts as a:

a) store of digestive enzymes

b) store of sodium ions

c) store of lipid

d) store of calcium ions

e) buffer of hydrogen ions

Question 03

An action potential arriving at the motor endplate causes release of:

a) acetylcholine which traverses the neuromuscular junction

b) sodium ions which binds to sodium receptors on the muscle membrane

c) calcium ions which initiate an action potential along the muscle fibre

d) noradrenaline which increases muscle metabolic activity

e) none of the above

Question 04

The trigger to initiate the contractile process in skeletal muscle is:

a) potassium binding to myosin

b) calcium binding to tropomyosin

c) ATP binding to the myosin cross bridges

d) calcium binding to troponin

e) ATP breakdown by actin

Question 05

After calcium ions have been released from the sarcoplasmic reticulum they:

a) initiate an action potential

b) cause sodium channels to open in the sarcolemmal membrane

c) bind to troponin

d) bind to actin

e) cause oxygen to be released from myoglobin

Question 06

A muscle fibre relaxes when:

a) the nerve stimulus is removed

b) the nerve stimulus is too forceful

c) the actin binding sites are uncovered

d) the actin binding sites are saturated

e) all the ATP is used up

Question 07

Fast-twitch fibres contain:

a) a relatively large number of mitochondria and low ATPase activity

b) a relatively small number of mitochondria and low ATPase activity

c) a relatively small number of mitochondria and high ATPase activity

d) a relatively large number of mitochondria and high ATPase activity

e) no mitochondria and high ATPase activity

Question 08

Type I muscle fibres have the following characteristics:

a) white, glycolytic, slow contracting

b) white, oxidative, slow contracting

c) red, oxidative, fast contracting

d) red, glycolytic, slow contracting

e) red, oxidative, slow contracting

Question 09

Which of the following is not an amino acid?

a) glutamic acid

b) aspartic acid

c) glutamine

d) palmitic acid

e) leucine

Question 10

What type of covalent bonds link the amino acids in a protein?

a) peptide bonds

b) hydrogen bonds

c) ionic bonds

d) glycosidic bonds

e) ester bonds

Question 11

Which of the following is an amino acid that is found in proteins?

a) adenosine

b) adenine

c) alanine

d) linoleic acid

e) creatine

Question 12

Which of the following factors can affect enzyme activity?

a) temperature

b) pH

c) the presence of certain metal ions

d) the addition or removal of phosphate

e) all of the above

Question 13

Prosthetic groups are:

a) required by all enzymes in the cell

b) loosely bound to enzymes via hydrogen bonds

c) sites on the enzyme molecule that permit allosteric modification of enzyme activity

d) linked to phosphate groups

e) tightly bound to enzymes and are required for their activity

Question 14

The initial rate of an enzyme catalysed reaction depends on:

a) the concentration of the enzyme

b) the concentration of the substrate

c) the affinity of the enzyme for its substrate

d) all of the above

e) none of the above

Question 15

Kinase reactions:

a) inhibit ATP breakdown

b) involve the addition or removal of a phosphate group

c) involve the addition or removal of a ketone group

d) involve the addition or removal of an amino acid to a polypeptide chain

e) involve the transfer of hydrogen atoms

Question 16

The energy for all forms of muscle contraction is provided by:

a) ATP

b) ADP

c) phosphocreatine

d) oxidative phosphorylation

e) generated in the mitochondria of the cell

Question 17

For very high force contractions lasting 1-2 seconds, the initial energy source is from:

a) glycolysis

b) creatine phosphorylation

c) phosphocreatine stores

d) ATP stores

e) none of the above

Question 18

Which of the following statements is false?

a) after a resistance training session the rate of protein synthesis in the exercised muscles is increased

b) after a resistance training session the rate of protein breakdown in the exercised muscles is increased

c) both (a) and (b)

d) protein cannot be used as a fuel for exercise

e) exercise increases the rate of secretion of growth hormone

Question 19

Which of the following is true?

a) increasing the protein intake above 3 grams per kg body mass per day will stimulate muscle growth and increase strength

b) creatine supplements can increase muscle strength and power

c) amino acid supplements can increase muscle strength and power

d) muscle damage is induced by shortening contractions

e) there is an inverse relationship between dietary protein intake and total energy intake

Oxford University Press, Online Resource Centre, Chapter 02.

Chapter 02

Instructions

Question 01

Question 02

Question 03

Question 04

Question 05

Question 06

Question 07

Question 08

Question 09

Question 10

Question 11

Question 12

Question 13

Question 14

Question 15

Question 16

Question 17

Question 18

Question 19