-Multiple nuclei located at the edge of the cell 

-A single skeletal muscle cell is long and approximately cylindrical in shape 
-Myofibril had rod like shape and it is a unit of the muscle cell
-Myofibril is compose of protein such as actin, myosin and titin
-These protein organise into think or thin filament called myofilament that repeat along the length of myofibril in sections called sarcomeres
-arrangement of contractile unit (sarcomeres) along the length of fibre give the cell striped appearance. 
-Think myofilament made up of protein myosin. It has rod like shape with 2 round heads at the end called cross bridges
-Thin myofilament made up of protein actin. It consist of double stranded coil and also contain regulatory protein called tropomyosin and troponin.
Function:
-Responsible for voluntary movement 

-Provide movement by muscle contraction

-Movement of limb, toe, neck etc. 
-Contract and make small adjustment to hold body in stationary position eg. sitting, standing
-Add stability to joints that have poor reinforcement 
-Contraction of skeletal muscle produce heat which help to maintain the body temperate

Involves reaction of actin and myosin (this is the same reaction that is produced in skeletal muscle contraction) 

smooth muscles are affected by two
neurotransmitters, aceticholine and norepinephrin

1)definition: 

Muscle tissue is a soft tissue that composes muscles in animal bodies, and gives rise to muscles' ability to contract. 

 

2) components (in general): 

Muscle tissue consists of long cells called muscle fibers, which contract in response to nerve signals 

 

This is opposed to other components or tissues in muscle such as tendons or perimysium.

Muscle tissue varies with function and location in the body. 

 

In mammals the three types are: 

-skeletal or striated muscle is responsible for voluntary movement
 

-smooth or non-striated muscle is responsible for involuntary body activities 

- cardiac muscle is responsible for contraction of the heart 
 

3)Structures and Functions 

Muscle tissue has some important functions, including: 

-Movement (both voluntarily and involuntarily) 

-Maintaining posture 

-Supporting soft tissues within body cavities 

-Guarding entrance and exists of the body 

-Maintaining body temperature 

-Striated like skeletal muscle 

-Cardiac muscle fibre branch and interconnected via intercalated disk 
-Gap junction located in the intercalated disk enable ionic communication and continuity between adjacent cardiac muscle fibres 

-Have a single central nucleus 
Function:
-Carry out unconscious task: contraction of the heart 

-Intercalated disk relay signal from cell to cell and help to synchronize heartbeat. 
-Exhibit autorhythmicity and spontaneously generate stimuli

Step A: Myosin head attaches to actin. (High energy ADP + P configuration)

Step B: Power stroke:  myosin head pivots pulling the actin filament toward the center.

Step C: The cross bridge detaches when a new ATP binds with the myosin.

Step D: Cocking of the myosin head occurs when ATP à  ADP + P. Another cross bridge can form.

Involves reaction of actin and myosin (this is the same reaction that is produced in skeletal muscle contraction) 

smooth muscles are affected by two
neurotransmitters, aceticholine and norepinephrin