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

Author Question: Explain the function of the lacrimal sac. What will be an ideal ... (Read 74 times)

OSWALD

  • Hero Member
  • *****
  • Posts: 580
Explain the function of the lacrimal sac.
 
  What will be an ideal response?

Question 2

Describe the layers of pleura and how they prevent friction caused by breathing.
 
  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

dpost18

  • Sr. Member
  • ****
  • Posts: 345
Answer to Question 1

The enlargement of the upper portion of the lacrimal duct is known as the lacrimal sac. Tears secreted by the lacrimal glands are pulled into this sac and subsequently forced into the nasolacrimal duct by the blinking action of the eyelids. The sac is dilated and pulls in fluid as the muscles associated with blinking close the lids. The sac constricts, forcing the fluid down the nasolacrimal duct as the lids are opened.

Answer to Question 2

The visceral pleura is the membrane that covers the outside of the lungs. The parietal pleura is the membrane that lines the pleural or lung cavities. Between these two pleura is a small space which is filled with a serous fluid to prevent friction when the lungs expand and deflate.




OSWALD

  • Member
  • Posts: 580
Reply 2 on: Jun 27, 2018
Excellent


hramirez205

  • Member
  • Posts: 345
Reply 3 on: Yesterday
Thanks for the timely response, appreciate it

 

Did you know?

Children with strabismus (crossed eyes) can be treated. They are not able to outgrow this condition on their own, but with help, it can be more easily corrected at a younger age. It is important for infants to have eye examinations as early as possible in their development and then another at age 2 years.

Did you know?

Stevens-Johnson syndrome and Toxic Epidermal Necrolysis syndrome are life-threatening reactions that can result in death. Complications include permanent blindness, dry-eye syndrome, lung damage, photophobia, asthma, chronic obstructive pulmonary disease, permanent loss of nail beds, scarring of mucous membranes, arthritis, and chronic fatigue syndrome. Many patients' pores scar shut, causing them to retain heat.

Did you know?

Side effects from substance abuse include nausea, dehydration, reduced productivitiy, and dependence. Though these effects usually worsen over time, the constant need for the substance often overcomes rational thinking.

Did you know?

Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.

Did you know?

Though the United States has largely rejected the metric system, it is used for currency, as in 100 pennies = 1 dollar. Previously, the British currency system was used, with measurements such as 12 pence to the shilling, and 20 shillings to the pound.

For a complete list of videos, visit our video library