energy system in muscle cells Flashcards
what is the only stage of respiration that can occur without the presence of oxygen?
glycolysis
what does pyruvate convert into
lactate
what causes lactate metabolism?
when muscle cells don’t get enough oxygen to support the electron transport chain, this results in an alternative respiratory pathway.
what is added to pyruvate during lactate metabolism?
hydrogen, NAD must ‘transfer’ its hydrogen to become free to allow glycolysis to continue.
lactate builds in the muscle tissues, why is this a problem?
the build up of lactate lowers the pH of muscle cells, causing acidosis in muscle tissue.
what is the pain in muscles called
muscle fatigue
why is the process of lactate metabolism reversible?
a period of rest allows the ocygen debt to be repaid.
what is myoglobin and what does it do?
myoglobin has a very high affinity for oxygen and binds with it. It extracts 02 from blood in high concentrations and stores it for muscle cells to use in aerobic respiration.
what are the 2 types of skeletal muscle fibres called
- fast twitch
- slow twitch
name some slow twitch muscle fibre properties.
contraction time : slow
respiration : aerobic
number of mitochondria: high
blood supply: good/better
myoglobin: high concentration
fuel used: fats
name some fast twitch muscle fibre properties.
contraction time : fast
respiration : anaerobic
number of mitochondria: fewer/less
blood supply: lower
myoglobin: lower concentration
fuel used: glycogen
what activities would best suit the muscle fibres?
fast twitch = sprint
slow twitch = marathon (endurance)