Lecture 11 -18

Which hormone listed below causes contraction of the smooth muscle of the uterus in terminal stages of pregnancy.  

oxytocin 

Which accessory protein in the sarcomere caps actin and regulates the length of the thin filaments?

tropomodulin 

Which muscle type below is voluntary and makes up most of the flesh of our limbs and also the covering musculature of our body. 

skeletal muscle

When the action potential or stimulus for contraction reaches the muscle fiber, the first thing that happens is:  

Calcium ions are released from the sarcoplasmic reticulum 

The sarcomere is the area on a skeletal muscle fiber which is located between two:

Z liness

For a relaxed sarcomere, choose the answer below that would fit for being present in the I Band region.  

only actin filaments

The cytoplasm of a muscle cell is called the:  

Sarcoplasm 

Muscle tissue is highly vascularized and innervated but does not have much connective tissue associated with it for its functional activity.

False

The actin filaments contain club-shaped extensions that contain ATPase which is utilized to break down ATP for muscle contraction.

False

The major function of the sarcoplasmic reticulum is to sequester phosphate ions for the production of ATP. 

False

The contractile unit of a muscle is called a:  

sarcomere 

Which skeletal muscle fiber type below is not found in human skeletal muscles.

Type III (slow glycolytic fibers)

Which hormone listed below causes contraction of the smooth muscle of the uterus in terminal stages of pregnancy.  

vasopressin

Individual muscle cells of this type have only one nucleus per cell and usually display a long slender form.  

smooth muscle 

Intercalated disks are junctions of two cardiac muscle fibers which occur only at the: 

I-band

Which muscle type below is categorized as involuntary and forms the musculature of most hollow organs such as the bladder and alimentary canal.

smooth muscle 

Which connective tissue fibers form a network which wraps itself around individual muscle fibers where smooth muscle fibers are arranged in bundles such as in the intestine.

Reticular Fibers