4.1: Skeletal Muscle Flashcards
Structure and Function
What percentage of cells in our bodies are muscle tissue cells?
60%
What is the study of activities and functions of the living body and support systems?
Physiology
smallest unit of chemical compound, always in motion, made up of atoms that are held together by chemical bonds formed from sharing or exchanging electrons
Molecule
any organized/specialized structure within a living cell (nucleus, mitochondria)
Sub-Cellular / Organelle
known as the ‘building blocks of life’, able to independently replicate themselves,; smallest structural and functional unit of all living things.
Cell
What are the two types of cells?
Prokaryotic and Eukaryotic
What type of cell has no nucleus (ie. bacteria) ?
prokaryotic
What type of cell has a nucleus (animals, plants, humans) ?
eukaryotic
collection of similar cells from the same origin that function together for a specific purpose
Tissue
group of tissues joined together to function for a specific purpose inside living organism
Organ
group of organs working together
Organ system
the material structure, as a whole, of any living thing
Organism
What are the 3 different “germ layers”?
ectoderm, mesoderm, endoderm
What is the endoderm?
becomes inner layer; becomes nervous system, and linings of various tubes and vessels
What is the ectoderm?
becomes outer layer; skin and other outer covering structures
What is the mesoderm?
becomes middle layer; skeleton, connective tissue, heart and muscle tissue
What is skeletal muscle?
under voluntary control and responsible for movement at all bodily joints; striated muscle
A muscle that has the shape of a spindle, wider in the middle and narrows at both ends. Greater range of motion but limited strength.
Fusiform
Muscle that is square shaped, with parallel fibers that run directly from origin to insertion
Quadrate
Muscle with wide origin that converges to a narrow insertion resembling a triangular shape
Triangular
Muscle with parallel fibers consisting of tendinous intersections that run perpendicular to the direction of the fibers
Longitudinal
Muscle fibers that run obliquely with respect to the tendon
Pennate muscles
Muscle where fibers are on the same side of the tendon
Unipennate
Muscle where fibers on both sides of the central tendon
Bipennate
Muscle where central tendon branches within a pennate muscle
Multipennate
Involuntary muscle; no “conscious control” over the muscle’s contraction; under control of the autonomic nervous system
Smooth Muscle
What do smooth muscles in the blood vessels do?
vasoconstriction (narrowing) and vasodialation (widening)
What systems are smooth muscles found?
blood vessels, digestive tract, reproductive, respiratory and urinary systems
What has a striated appearance and can hypertrophy but is involuntary and exhibits rhythmicity of contraction like smooth muscle.
Cardiac Muscle
Myofibrils are only found in which muscle fiber tissue type?
Skeletal
Which muscle tissue fatigues the quickest?
Skeletal
Which muscle tissue does not fatigue at all?
Cardiac
Which muscle tissue is controlled by the autonomic nervous system?
smooth
Which muscle tissue is controlled by the central nervous system?
cardiac
Which muscle tissue is stimulated by the nervous system to work?
skeletal
What are the 3 main functions of the skeletal muscles?
motion / resistance to external force; stabilization; heat production