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Date November 2018 Marks available 6 Reference code 18N.2.HL:.tz0.6
Level Higher Level Paper Paper 2 Time zone time zone 0
Command term Discuss Question number 6 Adapted from N/A

Question

Describe the need for glucose and oxygen by the brain.

[3]
a.

Using an example, describe how selective attention prevents information overload.

[3]
b.

Define motor programme.

[1]
c.i.

Apply the concept of motor programme to improving performance of a gymnastics routine.

[2]
c.ii.

Explain how genetic and environmental factors contribute to improved performance in long distance runners.

[5]
d.

Discuss how the three energy systems contribute to ATP production during an 800-metre run.

[6]
e.

Markscheme

glucose and oxygen are used to make ATP using aerobic respiration ✔

if the blood has low level of glucose or oxygen mental state can be altered negatively
OR
without glucose or oxygen, the person may experience dizziness or convulsions ✔

glucose storage in the brain is limited ✔

glucose moves rapidly into the brain cells ✔

a.

separates the relevant information from the irrelevant/noise information
OR
only relevant information is passed to the short-term memory ✔

an athlete concentrates on a specific cue or stimulus such as the ball/position of player and excludes the others such as the other players/cheering crowd ✔

can be improved by learning through past experience and interaction with

long-term memory ✔

operates in the short-term sensory store ✔

Award [2 max] only if no example is provided.

b.

motor programme is a set of movements stored as a whole in the memory «regardless of whether feedback is used in their execution»
OR
consists of an executive programme and subroutines✔

c.i.

practice of the motor programme/subroutines for a jump/gymnastic routine improves proficiency ✔

improved proficiency reduces executive programmes to subroutines as the movement has become more fluid ✔

this results in opportunity to practice more complex motor programmes such as a hand spring ✔

Accept any valid example that refers to a gymnastics routine.

c.ii.

Genetic factors:
a combination of height and flexibility allows for the optimal stride length and strength ✔

an athlete with more slow twitch/type I muscle fibres does better in long distance running ✔

an athlete with a higher lung capacity has an advantage in long distance running ✔

mental toughness/resilience enables runners to endure longer practices/training resulting in improvement in performance ✔

Environmental factors:
training maximizes the likelihood of obtaining a performance level with a genetically controlled ceiling ✔

balanced diet/proper nutrition high in «low glycemic index» carbohydrates are best for an endurance athlete ✔

technological aids «such as timing equipment» can help improve pacing and performance ✔

altitude training can improve endurance performance at sea level ✔

Award [2 max] for a list, [3 max] per factor.

d.

during «approximately» the first minute all energy systems will be working ✔

during an 800m run, energy systems do not respond in a sequential manner ✔

ATP-CP system:
ATP production is from the breakdown of phosphocreatine <anaerobically> during initial seconds of activity ✔

1 PC = 1 ATP ✔

may contribute at other times of rapid change in energy demand <as long as a steady state is found where the athlete settles into a pace> such as at the end of the race ✔

can only last for 10‐15 seconds/short burst ✔

Lactic Acid System:
partial breakdown of glucose anaerobically to produce ATP ✔

1 glucose molecule = <net> 2ATP ✔

will dominate after the ATP-PC system up to 1-2 minutes <while the aerobic system gets fully functional> ✔

The lactic acid system will dominate at other times where effort increases towards 100 % such as during the final sprint ✔

Aerobic System:
The aerobic system will dominate from approx. 1-2 minutes as the runner settles into their race pace ✔

1 glucose molecule = 38 ATP with the aerobic system ✔

Complete breakdown of glucose molecule in the presence of oxygen ✔

Award [3 max] for each energy system and [5 max] if only 2 energy systems are discussed

e.

Examiners report

Candidates struggled to identify the role oxygen played in the production of energy. Many candidates focused on the storage of carbohydrates, rather than focusing on glucose. However, generally candidates were able to describe the effect of limited glucose and oxygen.

a.

Candidates struggled to access all three marks for the question. Many were only able to achieve the first two mark points.

b.

Many candidates struggled to define a motor programme, and commonly gave very vague answers.

c.i.

Many candidates struggled to apply the concept of a motor programme; few candidates achieved more than 1 mark.

c.ii.

Generally candidates tried to balance their response and explain both factors. Candidates often listed the factors rather than explaining their effect.

d.

Candidates were able to describe basic elements of each system. However, candidates struggled to discuss their contribution and relationship during an 800m.

e.

Syllabus sections

Topic 3: Energy systems » 3.3. Nutrition and energy systems » 3.3.11. Evaluate the relative contributions of the three energy systems during different types of exercise.
Topic 3: Energy systems » 3.3. Nutrition and energy systems
Topic 3: Energy systems

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