CH 4: Muscular System Flashcards
responsible for body
movements, stabilizing joints, and generating
heat.
muscles
Muscles generate the force required to
cause movement by
contracting
a process in which proteins inside the muscle fibers overlap more than when they are at rest.
contracting
muscle function
- Produce Movement
- Maintain Posture and Body Position
- Stabilize Joints
- Generate Heat
- Additional Functions
_____ are packaged into organs
called skeletal muscles that attach to the skeleton.
Skeletal muscle fibers
Skeletal muscle fibers are packaged into organs called ____ that attach to the skeleton.
skeletal muscles
cover our bone and cartilage framework, they help form the smooth contours of the body
skeletal muscle
Skeletal muscle fibers are large, ______, multinucleate cells.
cigarshaped
Skeletal muscle is also known as (2)
striated muscle
voluntary muscle
no striations and is involuntary
Smooth muscle
difference in tissue and function
- skeletal muscle and smooth muscle
skeletal muscle
-striated
-voluntary
smooth muscle
-non striations
-involuntary
smooth muscle is found mainly in the walls of
hollow (tubelike) organs
Smooth muscle fiber characteristics
-shape
-nucleus
-surrounded
-arranged
shape- spindle-shaped
nucleus-uninucleate
surrounded- scant endomysium
arranged-two layers (circular and longitudinal)
spindle-shaped, uninucleate, and surrounded by scant endomysium and are arranged in two layers (circular and longitudinal)
smooth muscle fibers
striated, uninucleated and under involuntary control
cardiac muscle
The cardiac cells are cushioned by small amounts of endomysium and are arranged in
spiral or figure
8–shaped bundles
branching cells joined by special gap junctions called intercalated discs
cardiac muscle
Cardiac muscle fibers are branching cells joined by special gap junctions called
intercalated discs
are the structural and functional
units of skeletal muscle.
sarcomeres
precise arrangement of even smaller structures within sarcomeres– Thick and Thin Myofibrils
myofilaments
interconnecting tubules and sacs that is used for store calcium and to release it on demand when the muscle fiber is
stimulated to contract
Sarcoplasmic reticulum
Sarcoplasmic reticulum interconnecting tubules
and sacs that is used for
store calcium and release
Muscle fibers have several special functional properties (3)
Irritability
Contractility
Extensilibity
also called responsiveness, which is
the ability to receive and respond to a stimulus.
Irritability