run for your life Flashcards
name 2 molecules needed for aerobic respiration that can move into the mitochondria
pyruvate
oxygen
reduced NAD / ADP
the outer mitochondrial membrane is not permeable to hydrogen ions.
explain the importance of this feature of the membrane
to stop H+ diffusing out (of mitochondrion)/ into cytoplasm
maintaining a high concentration (of H+) in the inter membrane space
so H+ can move down conc grad
by chemiosmosis
to synthesise ATP
explain why some ATP is broken down during glycolysis
donated phosphate to/ phosphorylates glucose
supplies energy to break down the glucose
to produce trios phosphate
explain the role of carrier molecules in the electron transport chain
receive hydrogen from reduced NAD/ FAD
break hydrogen into H+ and e-
electrons transferred by a series of redox reactions
energy released is used to pump H+ into inter membrane space
liver cells can absorb lactate from the blood
deduce what happens to the lactate in these cells
oxidised to form/ converted to pyruvate
pyruvate converted to glucose/ glycogen
pyruvate/ glucose used in respiration
explain the need for reduced NAD to be oxidised in a mitochondrion
so that hydrogen can be delivered to the etc
to allow ATP synthesis/ chemiosmosis
to regenerate NAD
describe how the concentration of calcium ions around the myofibrils is controlled
calcium ions released from SR
in response to nerve impulse/ action potential in neuromuscular junction
calcium channels open to allow calcium ions to cross membrane/ enter sarcoplasm
calcium ions taken back up into SR by active transport
which structure joins bone to bone in an elbow joint
ligaments
describe the changes caused when Ca2+ bind to troponin
tropomyosin is moved by troponin
myosin binding sites on actin are exposed
explain how myosin binding sites being exposed causes muscles to contract
myosin heads can bind to binding sites
myosin changes shape
actin filaments slide/ pulled over the myosin
muscle fibres/ myofibril/ sarcomeres shorten
ATP hydrolysed
describe the interaction between troponin and tropomyosin that allows muscle contraction
troponin changes shape
causing tropomyosin to move away from the myosin binding sites
explain the importance of the primary structure for the functioning of ATPase
primary structure determines interactions between amino acids/ R groups
determines folding/ tertiary structure
affecting shape of active site
active site is complementary to ATP
explain how the extensor and flexor muscles bring about movement of the lower leg
tendons attach muscles to bones
muscles act as an antagonistic pair
when the extensor muscle contracts, it pulls on the tibia to extend the leg
when the flexor muscle contracts, it pulls on the fibula flexing the leg
describe 2 structural differences between fast and slow twitch muscle fibres
fast have no/ few mito, slow have many
fast have no/ few caps present, slow have many
explain how the structure of a muscle fibre is related to its specialised function
sarcolemma contains voltage gates channels to allow depolarisation of muscle fibre
many mito for aerobic respiration/ to supply ATP
presence of myofibrils/ actin and myosin
myofibrils allow contraction of muscle
describe how the tertiary structure of myosin is related to its function
part folded into a specific shape w globular head
that can bind to actin
myosin has a site that can bind w ATP
part straight to form a bundle w other myosin molecules
