Analyse the movement at the knee and hip as the rower moves from position A to position B in the diagram.

Outline one type of muscle tissue.

Describe how the characteristics of slow-twitch muscle fibres are suited to a rower.

Describe the production of ATP from fatty acids.

Discuss the increased maximal oxygen consumption of athletes after a period of endurance training.

Knee joint:
extension;

agonist is the quadricep/rectus femoris;*

concentric contraction of agonist/quadricep;

antagonist is the hamstrings;

Hip joint:
extension;

agonist is the gluteus maximus;

concentric contraction of agonist/gluteus maximus;

antagonist is the iliopsoas;

Quadricep group is acceptable.
*Direct reference to agonist/prime mover as cause of extension is required.

Cardiac:
striated branches <of intercalated discs>;

myogenic/specialized cells contract on their own intrinsic rhythm
OR
involuntary muscle tissue which cannot be controlled consciously;

contracts to pump blood/only example is the heart;

extremely high resistance to fatigue;

Smooth:
non-striated tissue/spindle shaped tissue;

predominantly involuntary muscle <which cannot be consciously controlled>
OR
sustain long periods of contractions;

often found in the walls of hollow organs/blood vessels/eyes
OR
moves food/regulates blood flow/secretions;

Skeletal:
striated in appearance <due to cylindrical cells>;

voluntary control of contractions by nerve impulses
OR
contract in short, intense bursts;

attached to bones/ the skeleton <via tendons>;

support posture/movement of the skeletal system;

produces heat and protects organs;

Muscle type must be named to be awarded marks.

Award [2] max for characteristics from only one muscle type (the one with the highest total marks).

high capillary density which allows large amounts of oxygen/nutrients to be delivered during rowing;

high myoglobin content which allows for increased transport of oxygen from capillaries into the cell;

high number of mitochondria which allows greater ATP production through aerobic processes;

high triglyceride stores therefore greater aerobic capacity and ability to metabolize large amount of ATP for rowing;

therefore greater fatigue resistance and ability to maintain performance during distance rowing;

fatty acids are broken down by beta oxidation;

catabolized into acetyl CoA;

acetyl CoA enters the Krebs cycle;

electrons are released from the Krebs cycle and beta oxidation into the electron transport chain;

produces triple the amount of glycogen / 100–150 ATP;

waste products are CO₂ and water;

endurance training results in increased stroke volume / left ventricular volume;

therefore increase in cardiac output;

endurance training results in increased capillarization of muscle
OR
therefore increased delivery of blood flow to working muscles;

endurance training results in increased hemoglobin;

endurance training results in increased myoglobin
OR
therefore increase in arteriovenous oxygen difference;

A mixture of answers. Responses concerning the knee joint were generally answered better than those for the hip joint.

Generally well answered.

Challenging for the students to achieve full marks.

Quite poor answers.

Very average and some students did not interpret the question appropriately, responding about something other than VO₂max