Tag: locomotion and movements

Quizzes (15) Questions (132)

Questions Related to locomotion and movements

Multiple choice muscle contraction locomotion and movements biology

In hurdle race, what is the major energy source of the leg muscle?

  1. ATP

  2. Glycolysis

  3. Pyruvate and lactate

  4. Oxidative metabolism
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The source of energy that is used to power the movement of contraction in working muscles is adenosine triphosphate (ATP).
  • ATP is considered as the energy currency of the cell.
  • Hence In a hurdle race, what is the major energy source of the leg muscle ATP. It helps in muscle contraction that facilitates running in the race.
  • So, the correct answer is 'ATP'.
Multiple choice muscle contraction locomotion and movements biology

Electron microscopic studies of the sarcomeres have revealed that during muscle contraction

  1. The width of A-band remains constant

  2. The width of the H-zone becomes smaller

  3. The width of I-band increases

  4. The diameter of the fibre increases
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During muscle contraction, the A - band with a length of 1.85 micrometers does not undergo any contraction. However, the I-bands and the H-zone shorten. This causes the Z lines to come closer together. So, the correct answer is 'The width of A-band remains constant'.

Multiple choice muscle contraction locomotion and movements biology

In hurdle race, what is major source of energy to leg muscle?

  1. Preformed ATP

  2. Oxidative metabolism

  3. Pyruvate and lactate

  4. Glycolysis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

  • In the hurdle race, a person requires energy production faster than our bodies can adequately deliver oxygen. 
  • In those cases, the working muscles generate energy anaerobically. This energy comes from glucose through a process called glycolysis, in which glucose is broken down or metabolized into a substance called pyruvate through a series of steps.
  •  When oxygen is limited, the body temporarily converts pyruvate into a substance called lactate, which allows glucose breakdown and thus energy production to continue.
  •  The working muscle cells can continue this type of anaerobic energy production at high rates for one to three minutes, during which lactate can accumulate to high levels.
Hence, In the hurdle race,  Oxidative metabolism is a major source of energy to the leg muscle.
   So, the correct answer is 'Oxidative metabolism'.

Multiple choice muscle contraction locomotion and movements biology

Which statement is correct for muscle contraction : - 

  1. Length of H-zone become decrease

  2. Length of A-band remains constant

  3. Length of I-band become increase

  4. Length of two Z-line become increase
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation
Upon muscle contraction, the A-bands do not change their length (1.85 micrometres in mammalian skeletal muscle), whereas the I-bands and the H-zone shorten. This causes the Z lines to come closer together.

So, the correct answer is 'A, B'.
Multiple choice muscle contraction locomotion and movements biology

Name the ion responsible for masking active sites for myosin for cross-bridge activity during muscle contraction.

  1. Potassium

  2. Calcium

  3. Magnesium

  4. Sodium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Active sites for myosin(Thick filament) are present on actin which are masked by troponin in resting state. when  Ca++ level increases it leads to the binding of calcium with a subunit of troponin on actin(thin) filaments and thereby remove the masking of active sites for myosin.
  • Utilizing the energy from ATP hydrolysis, the myosin head now binds to the exposed active sites on actin to form a cross bridge. 
  • This pulls the attached actin filaments towards the centre of ‘A’ band.
  •  The ‘Z’ line attached to these actins are also pulled inwards thereby causing a shortening of the sarcomere, i.e., contraction.
  • Hence the ion responsible for masking active sites for myosin for cross-bridge activity during muscle contraction is calcium.
  • So, the correct answer is 'Calcium'
Multiple choice muscle contraction locomotion and movements biology

Sarcoplasmic reticulum of muscle fibres is the storehouse of

  1. Calcium

  2. Sodium

  3. Chloride

  4. Potassium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The endoplasmic reticulum, i.e., sarcoplasmic reticulum of the muscle fibres is the storehouse of calcium ions.
  • A neural signal reaching this junction releases a neurotransmitter (Acetylcholine) which generates an action potential in the sarcolemma. This spreads through the muscle fibre and causes the release of calcium ions into the sarcoplasm from the sarcoplasmic reticulum and initiate the mechanism of muscle contraction.
  • Hence sarcoplasmic reticulum of muscle fibres is the storehouse of calcium.
  • So, the correct answer is 'Calcium'.
Multiple choice muscle contraction locomotion and movements biology

Immediate source of energy for muscle contraction is

  1. Glucose

  2. GTP

  3. Creatine phosphate

  4. ATP
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  •  Active sites for myosin are present on actin which are masked by troponin in resting state. When Ca++ level increases it leads to the binding of calcium with a subunit of troponin on actin(thin) filaments and thereby remove the masking of active sites for myosin.
  • Utilizing the energy from ATP hydrolysis, the myosin head now binds to the exposed active sites on actin to form a cross bridge. 
  • This pulls the attached actin filaments towards the centre of ‘A’ band.
  •  The ‘Z’ line attached to these actins are also pulled inwards thereby causing a shortening of the sarcomere, i.e., contraction. The myosin, releasing the ADP and P1 goes back to its relaxed state. Hence immediate source of energy for muscle contraction is ATP.
  • So, the correct answer is 'ATP'.
Multiple choice muscle contraction locomotion and movements biology

Source of $Ca^{2+}$ for muscle contraction is both sarcoplasmic (endoplasmic) reticulum as well as extracellular fluid in case of
a.  Skeletal muscles
b. Smooth muscles
c. cardiac muscles 

  1. a only

  2. b and c only

  3. a and c only

  4. b only
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Both smooth muscle and cardiac muscle utilise sarcoplasmic and extracellular fluid as source of calcium ion, which is in contrast to skeletal muscle which derive it from sarcoplasm only.

So, the correct option is 'b and c only'

Multiple choice muscle contraction locomotion and movements biology

State whether the following statements are true or false.
Cross bridges pull the actin chain as the myosin heads return to their unenergized conformation.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • A sarcomere is the basic unit of muscle tissue in both cardiac and skeletal muscle. Myofibril activity is required for muscle contraction on the molecular level. 
  • When ATP binds to myosin, it separates from the actin of the myofibril, which causes a contraction.
  • The muscle contraction cycle is triggered by calcium ions binding to the protein complex troponin, exposing the active-binding sites on the actin.
  • ATP then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.
So, the correct option is 'True'.

Multiple choice muscle contraction locomotion and movements biology

Which response to overcooling does not involve muscle contraction?

  1. Blood vessels narrowing

  2. Hairs standing up

  3. Shivering

  4. Reduced sweating
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In response to over-cooling, 

muscles allow blood vessels narrowing(circular muscles), piloerection(hair standing up by erector pili muscles), and shivering.
Reduced sweating does not involve muscle contraction or relaxation.
So, the correct answer is 'Reduced sweating'.