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 28 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?

About one in five American adults and teenagers have had a genital herpes infection—and most of them don't know it. People with genital herpes have at least twice the risk of becoming infected with HIV if exposed to it than those people who do not have genital herpes.

Did you know?

Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.

Did you know?

Patients should never assume they are being given the appropriate drugs. They should make sure they know which drugs are being prescribed, and always double-check that the drugs received match the prescription.

Did you know?

Though newer “smart” infusion pumps are increasingly becoming more sophisticated, they cannot prevent all programming and administration errors. Health care professionals that use smart infusion pumps must still practice the rights of medication administration and have other professionals double-check all high-risk infusions.

Did you know?

Vaccines prevent between 2.5 and 4 million deaths every year.

For a complete list of videos, visit our video library