TEAS 7 - Science (Muscular System) Flashcards
One of three major muscle types, this muscle is found only in the heart.
cardiac muscle
___ are very fine contractile fibers, groups of which extend in parallel columns along the length of striated muscle fibers.
Myofibrils
The ___ is the fundamental unit of contraction and is defined as the region between two Z-lines.
sarcomere
___ are thin filaments of protein that form (together with myosin) the contractile filaments of muscle cells, and are also involved in motion in other types of cells.
Actin
___ are thick filaments of fibrous protein that form (together with actin) the contractile filaments of muscle cells and are also involved in motion in other types of cells.
Myosin
Muscles move bones by ___ and ___.
contracting
relaxing
There are 3 types of muscles. What are they?
- skeletal muscle
- cardiac muscle
- smooth muscle
___ muscle moves bones and generates heat.
Skeletal muscle
Skeletal muscle moves ___ and generates heat.
bones
The cells in skeletal muscle are called ___ and they contain a reddish pigment called ___. These cells have ___ nuclei.
myocytes
myoglobin
multiple
If you looked at skeletal muscle under a microscope, you would see that it has tiny lines called ___.
striations
The striations of skeletal muscle mark the contractile units called ___. In other words, between each set of striations is a sarcomere.
sarcomeres
What is between each set of striations?
a sarcomere
The myocytes also contain ___ nuclei.
multiple
___ muscle looks a lot like skeletal muscle since it is also striated.
Cardiac muscle
Why do cardiac muscle and skeletal muscle look alike?
they both have striations
The cells of cardiac muscles are called ___. These cells have ___ nucleus
cardiomyocytes
1
Cardiac muscle contains special cell junctions called ___ ___.
intercalated discs
___ muscle contains special cell junctions called intercalated discs which help the cells contract ___ which is important in moving blood through the ___.
Cardiac muscle
together
heart
Smooth muscle has a ___ organized structure than skeletal or cardiac muscle.
less
Smooth muscle contains cells with only ___ nucleus and there are __ striations.
1
no
What is the only type of muscle without striations?
smooth muscle
What is the only type of muscle with intercalated discs?
cardiac muscle
What is the only muscle cell with multiple nuceli?
myocytes (skeletal muscle)