Negative Feedback - the system which maintains a condition in the body within a narrow range by detecting and counteracting a change bringing the level back to normal.
Receptors - used to detect deviations from the norm.
Effector - carries out response which brings about a corrective change.
Homeostasis - the maintenance of a stable internal environment.
Thermoregulation - temperature control in the body, controlled by the Hypothalamus.
Respirometer - a piece of equipment that measures the rate of oxygen being taken up by an organism and therefore the rate of respiration.
Glycolysis - the first stage of respiration, the ‘splitting of sugar’. Takes place in the cytoplasm.
Phosphorylation - The addition of phosphate molecules to a glucose molecule to increase its reactivity, produces TP. Catalysed by Phosphofructokinase.
Oxidation - the removal of H+ ion from TP to form pyruvate.
Skeletal muscle - muscles which allow us to move, under the control of the voluntary nervous system, attached to bones.
Myofibrils - long, cylindrical organelles within each muscle fibre, made up of proteins which are highly specialised for contraction.
Sarcomere - units which make up a myofibril made up of actin and myosin.
Sarcolemma - the cell membrane of muscle fibres.
Sarcoplasm - the cytoplasm of the muscle cells.
Sarcoplasmic Reticulum - a network of internal membranes which runs through the sarcoplasm, stores and released Ca2+ ions that are needed for muscle contraction.
Myosin - thick myofilaments that appear dark under a microscope (A bands).
Myosin Heads - globular head on the myosin which is hinged so it can move back and forth. Has a binding site for actin and ATP.
Actin - thin myofilaments that appear light under a microscope (I bands). Have actin-myosin binding sites.
Tropomyosin & Troponin - Two proteins that are found between actin filaments, they are attached to each other and help myofilaments move past each other.
Cross-Bridges - form when myosin heads bind with myosin binding sites on the actin.
Slow Twitch Muscle Fibres - muscle fibres which are adapted for steady action over a period of time, which contract relatively slowly.
Fast Twitch Muscle Fibres - muscle fibres which are adapted for rapid bursts of activity, which contract very rapidly.
Cartilage - found between bones, a good shock absorber, hard but flexible, elastic and able to withstand compressive forces.
Tendons - join muscle to bone, gives a secure…