This topic contains a solution. Click here to go to the answer

Author Question: Blepharoptosis is drooping of the eyelids. Indicate whether the statement is true or ... (Read 94 times)

Metfan725

  • Hero Member
  • *****
  • Posts: 552
Blepharoptosis is drooping of the eyelids.
 
  Indicate whether the statement is true or false

Question 2

Explain how a muscle fiber contracts.
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

stillxalice

  • Sr. Member
  • ****
  • Posts: 339
Answer to Question 1

TRUE

Answer to Question 2

Each muscle fiber is connected to a single nerve cell at the neuromuscular junction. When the electrical impulse reaches the end of the nerve cell, the nerve cell releases the neurotransmitter acetylcholine. Acetycholine is a chemical messenger that moves across the neuromuscular junction and acts as a key to unlock receptors on the muscle fiber. This changes the permeability of the cell membrane and allows calcium ions to flow into the muscle fiber. Calcium ions cause the thin filaments to slide between the thick filaments, shortening the muscle and producing a muscle contraction.




stillxalice

  • Sr. Member
  • ****
  • Posts: 339

 

Did you know?

The eye muscles are the most active muscles in the whole body. The external muscles that move the eyes are the strongest muscles in the human body for the job they have to do. They are 100 times more powerful than they need to be.

Did you know?

Less than one of every three adults with high LDL cholesterol has the condition under control. Only 48.1% with the condition are being treated for it.

Did you know?

Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.

Did you know?

Critical care patients are twice as likely to receive the wrong medication. Of these errors, 20% are life-threatening, and 42% require additional life-sustaining treatments.

Did you know?

Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.

For a complete list of videos, visit our video library