AP chapter 8 Flashcards
Each fine thread is a muscle cell usually called a ___
muscle fiber
What are three muscle fibers types?
skeletal, cardiac, and smooth
Threadlike cylindrical ___ cells appear in bundles
skeletal muscle
What are the 3 names for Skeletal muscle?
#1 skeletal muscle because it attaches to bone #2 striated muscle because of its cross stripes or striations #3 voluntary muscle because its contractions can be controlled voluntarily
The bulk of the heart is made up of ___
cardiac muscle
What two muscles are involuntary?
Cardiac muscle and smooth muscle
___ fibers are tapered at each end and have a single nucleus
smooth muscle
What are 4 names for the Smooth muscle?
#1 smooth muscle #2 nonstriated muscle fibers, because they lack cross stripes on striations #3 involuntary, because we normally do not have control over their contractions #4 visceral muscle
___forms an important part of the walls of blood vessels and of many hollow internal organs (viscera) such as the gut, urethra, and ureters
smooth muscle
Group of muscle fibers are called
fascicles
___ is the loose connective tissue outside the muscle organs that forms a flexible, sticky “packing material” between muscles, bones, and the skin
Fascia
The muscle’s attachment to the more stationary bone is called its ___
origin
The muscle’s attachment to the more movable bone is called the muscle’s ___
insertion
The entire muscle (except its two ends) is called the ___
body of the muscle
Small fluid-filled sacs called ___ lie between some tendons and the bones beneath them
bursae
The synovial membrane secretes a slippery lubricating fluid, called synovial fluid, that fills the ___
bursae
___ reduces friction and makes it easier for a tendon to slide over a bone when the tendon’s muscle shortens
bursa and tendon sheaths also
What encloses some tendons?
tendon sheaths
The fiber’s internal framework is organized into many long cylinders, each made up of two kinds of thread-like microfilaments called ___ and ___
thick and thin myofilaments
The thick myofilaments are formed from a protein called ___
myosin
thin myofilaments are composed mainly of the protein called ___
actin
Muscle fibers are also called ___
contractile cells
The basic contractile unit of skeletal muscle
sarcomere
The repeating units, or sarcomeres, are separated from each other by dark bands called ___
Z lines or Z disks