Finish muscles, circulatory system -- Lecture 22 Flashcards
(38 cards)
2 types of skeletal muscle fibers:
slow-twitch fibers (characteristics)
generate full contractions more slowly but are very resistant to fatigue
has a darkish red color (dark meat)
2 types of skeletal muscle fibers:
fast-twitch fibers (characteristics)
generate full contractions quickly but also fatigue much more quickly
is white in color (white meat)
2 types of skeletal muscle fibers:
muscles are a ___ of fast and slow-twitch muscle fibers
% depends on a ___
mix
muscle’s function
muscle function and fiber composition:
postural muscles –
what do they do?
what is their muscle fiber composition?
can maintain continuous contractions and are slow to fatigue
have a high % of slow-twitch fibers
muscle function and fiber composition:
bicep muscles –
what do they do?
what is their muscle fiber composition?
generate full contractions quickly, but also fatigue quickly
have higher percentage of fast-twitch fibers
fiber type composition naturally ___ in people
varies
fiber type composition naturally varies in people:
marathon athletes fiber type composition
more slow-twitch fibers than fast-twitch
fiber type composition naturally varies in people:
middle distance athletes fiber type composition
have roughly the same % of fast-twitch as slow-twitch
fiber type composition naturally varies in people:
spinters’ fiber type composition
more fast-twitch fibers than slow-twitch
fiber type composition naturally varies in people:
exercises that engage particular fibers will make those fibers ___ and more ___
larger and more efficient
muscle energy generation:
muscle performance depends on ___
ATP supply
muscle energy generation:
muscles have ___ ATP supply systems
3
muscle energy generation:
3 muscle ATP supply systems:
immediate system –
what does it do
how long does it last
uses existing ATP supplies and ATP regenerated using phosphocreatine
lasts 30 seconds
muscle energy generation:
3 muscle ATP supply systems:
how is phosphocreatine created in the immediate system?
creatine kinase transfers a phosphate group to ADP –> produces phosphocreatine
muscle energy generation:
3 muscle ATP supply systems:
what is phosphocreatine?
an energy reserve
muscle energy generation:
3 muscle ATP supply systems:
glycolytic system –
what does it do
how long does it last
metabolizes readily available carbohydrates to generate ATP
lasts 10-15 minutes
muscle energy generation:
3 muscle ATP supply systems:
oxidative system –
what does it do
how long does it last
metabolizes stored carbohydrates and fats to generate ATP
lasts until muscle failure
circulatory system:
a circulatory system functions to ___
transport materials around the body
circulatory system:
multicellular organisms need to:
deliver oxygen and nutrients to and waste products from all cells in the body
circulatory system key components:
muscular pump – the heart
fluid – blood or hemolymph
series of conduits – blood vessels
categories of circulatory systems:
open circulatory system:
fluid exits the vessels, flows thru the tissues, then returns to the heart and the vessels
categories of circulatory systems:
closed circulatory system:
fluid never exits the vessels, is contained in a continuous system of vessels
open circulatory system (insects)
what happens?
a tubular heart pumps the circulatory fluid (hemolymph) thru vessels
hemolymph leaves the vessels
disperses thru the tissues –> returns to the heart thru openings called ostia
open circulatory systems (insects):
hemolymph (definition)
circulatory fluid in insects
has hemocyte instead of red blood cells
has hemocyanin instead of hemoglobin (blue-green color)
