Muscles Flashcards
What are the three types of muscle?
Skeletal, cardiac, smooth
Which type of muscle moves joints by strong and rapid contractions?
Skeletal muscle
Which two types of muscles are involuntary?
Cardiac and Smooth Muscle
What type of nucleus does a skeletal muscle have?
Multinucleated
What type of nucleus does a cardiac muscle have?
Single central nucleus often branched
What type of nucleus does a smooth muscle have?
Single central nucleus
What type of junction do cardiac muscles contain?
Gap junctions, adherens junctions, desmosomes
What type of muscles are tightly connected by specialized junctions?
Cardiac muscle
What shape are smooth muscles?
Spindle shaped
Where are smooth muscles found?
Found in walls of most blood vessels and tubular organs
What is the function of gap junctions?
Allow cells to be electrically coupled, so that they beat in synchrony
What is a static bone?
Point of origin of muscle connection
What is a moving bone?
The point ofinsertion of a muscle connection
What is an antagonistic pair?
when one contracts, the other relaxes to enable opposing movements
Examples of opposing movements
Flexion versus extension
Abduction vs adduction
Protraction vs retraction
What are flexor muscles?
Any of the muscles that decrease the angle between the two sides of a joint
Example of flexor muscle
bending the elbow or knee
What is an extensor?
Any of the muscles that increase the angle between two sides of a joint
Example of extensor
Straightening the elbow or knee
What are the 3 parts of the jointed exoskeleton of the hind leg?
Femur, tibia, tarsus
What are the 2 antagonistic muscles that connect an insect leg’s femur and tibia?
flexor tibiae muscle and extensor tibiae muscle
What happens when the flexor muscle contracts and the extensor muscle relaxes?
the tibia and femur are brought closer together
What happens when the extensor muscle contracts and the flexor muscle relaxes?
the tibia is pushed away from the femur
