1/15
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
4 characteristics of skeletal muscle
Prefixes
Mus- little mouse
Myo- muscle
Sarco- flesh
Nearly ½ of a body’s mass is skeletal muscle (40%)
Essential function is contraction
Muscles are machines
→ they pull on bones to create movement
Epimysium
Tough, connective tissue covering of the muscle
Fascicles
Bundles of muscle fibers that make up individual muscles
Muscle fiber
Individual muscle cell
Perimysium
Tough, fibrous connective tissue covering the fascicle
Endomysium
Delicate connective tissue covering the muscle fiber
Myofibril
Large ribbon like structures; extended end to end of muscle fiber
Membrane potential
Difference in charge across a cell’s membranes
Like a tiny battery
Needed for nerves, muscles, and normal cell fxn
Graded response
The strength of response can change
Happens in muscles and nerves
It depends on how much stimulation is sent like from a nerve is sent
ATP and how it is broken down
ATP: Adenine, ribose, 3 phosphate groups
It gets broken down when the body needs energy
Important for muscle contraction
3 ways ATP can be regenerated
Direct phosphorylation of ADP and CP
Aerobic respiration
Anaerobic respiration + lactic acid fermentation
Muscle fatigue
Occurs when
Muscles are excersized strenuously for a long time
Even though the cells are stimulated they can not contract bc a muscle can only do as much work as how much o2 is available
Skeletal
Several nuclei
Movement is voluntary
Situations = yes
Shaped: single, long, cylindrical
O2 debt= yes
Fastest
Cardiac
One nuclei
Involuntary
Striations = yes
Shaped: branching chains of cells connected
O2 debt = yes
Middle
Smooth
One nuclei
Movement is involuntary
Striations = no
Shaped: Fusiformis (spindle shaped) tapered at both ends
O2 debt = no
Slowest
Types of movement
Flexion: bones get closer, angle decreases
Extension: bones get father apart, angle increases
Abduction: Moving Away from middle
Adduction: Moving Towards middle
Circumduction: Combination of F/F, A/A in ball and socket joint
Rotation: movement around the longitudinal axis