Date | May 2022 | Marks available | 4 | Reference code | 22M.2.SL.tz0.5 |
Level | Standard Level | Paper | Paper 2 | Time zone | time zone 0 |
Command term | Explain | Question number | 5 | Adapted from | N/A |
Question
Distinguish the characteristics of smooth and cardiac muscle.
Describe how a long jumper can manipulate the factors that affect projectile motion to increase their distance jumped during a competition.
A chronic adaptation of aerobic training is an increase in hemoglobin. Outline how this adaptation would benefit an athlete running a marathon.
Explain why an elite basketballer would be able to process relevant sporting signals more effectively than a novice.
Using examples from sport, compare motor programmes from both open-loop and closed-loop perspectives.
Markscheme
Candidates must distinguish muscle characteristics to be awarded a mark.
Accept any suitable example of the location of smooth muscle. Do not accept organs only.
Accept any accurate additional structural difference.
velocity / speed of take-off:
increasing acceleration / momentum so that their greater force at take-off results in greater distance;
ensure their run up is long enough to so that they are at maximum speed;
ensure their run up is measured so that they do not do any stutter steps and lose speed;
ensure that they jump off their favoured foot for maximum power transfer;
angle of take-off:
alter angle of take-off by jumping higher or lower to achieve optimal release angle;
height of take-off:
centre of mass higher on take-off than landing to increase flight time
OR
raising arms leads to a higher centre of mass which leads to greater flight time / distance jumped;
Max [1] if 3 factors are only listed.
Max [3] if only 1 described factor is given.
improved oxygen transport <from the lungs> to the muscles;
increased oxygen levels allow the body to utilize aerobic system to a greater degree;
wider availability / variety of fuel sources as aerobic system can use carbohydrates, fats and protein as fuels;
reduced reliance of lactic acid system which produces fatiguing byproducts;
able to work at a higher intensity for a longer period without fatigue;
improved A-VO2 difference / efficiency of oxygen exchange;
elite athlete:
detection:
able to filter actual signals from the distraction of “noise”;
can correctly interpret signals more than novice athlete due to experience;
selective attention to correct stimulus / ability to detect signals sooner than novice;
comparison:
has a more extensive long-term memory bank to draw on to compare the stimuli to;
recognition:
the process of finding a corresponding stimulus in memory is more developed;
able to spend little/no attention focused on executing movement they are in autonomous phase of learning therefore full focus on signals received;
Accept appropriate explanation in the converse.
closed loop:
e.g. handstand in gymnastics / downhill skiing;
error detection made during the execution of motor programme;
correction made during execution of motor programme;
memory trace: recall of previous actions initiates action;
memory trace strengthened from practice and feedback;
perceptual trace: guidance of body part during the action. In the event of an error the limb is adjusted;
open loop:
e.g. action phase of a golf swing / hitting a baseball;
postulated that movements require attention only for initiation of the first action;
feedback is received however ongoing movements cannot be modified when unforeseen changes occur;
Max [4] per loop.
Max [2] for correct sporting examples; open [1] and closed loop [1] perspectives.
Examiners report
Many candidates were able to clearly identify a location of cardiac muscle within the heart. Many candidates correctly identified that smooth muscle is found within organs such as the stomach or intestines. However, many candidates just identified organs as the location and therefore were not credited the mark. Most candidates correctly identified cardiac muscle fibres have striations whereas smooth does not. Very few referred to nuclei and appeared to have a misconception that smooth muscles was multinucleated. As the question was distinguish, nuclei were not included in the mark scheme as both cardiac and smooth are uninucleate, although we appreciate some cardiac muscle can be binucleated therefore if candidates correctly distinguished between the two muscles, credit would have been provided.
This was one of the more popular questions for question 5. Candidates appeared to be well prepared for this question and applied their knowledge effectively. G2 forms raised concerns about this question, however candidates approached this question logically. Many candidates were able to explain how experience of training lead to elite athletes being able to filter noise more easily, develop more selective attention, use their memory to compare stimuli and are able to focus their attention to signals as they are autonomous in their skills. This was a strong area for candidates.
This was the question students struggled the most with completing, several candidates who chose question 5 skipped this part. Closed and open loop should be an area all schools should review for the future.