Author Question: What is the total volume of one side of a hemocytometer if the ruled area is 3 3 mm and the depth ... (Read 27 times)

futuristic

  • Hero Member
  • *****
  • Posts: 638
What is the total volume of one side of a hemocytometer if the ruled area is 3  3 mm and the depth is 0.1 mm?
 
  a. 0.3 mm3
  b. 0.9 mm3
  c. 1.0 mm3
  d. 9 mm3

Question 2

Which of the following would cause a manual cell count to be falsely high?
 
  a. Unopette not mixed before charging the hemocytometer
  b. Not wiping excess blood from outside of pipette when filling
  c. Using a smaller volume pipette than that specified by the Unopette system
  d. Pulling blood out of the pipette when wiping away excess on the outside



kishoreddi

  • Sr. Member
  • ****
  • Posts: 329
    • Your online Help in Biology and chemistry
Answer to Question 1

ANS: B
Volume = area  depth = (3  3)  0.1 = 0.9 mm3

Answer to Question 2

ANS: B
Blood left on the outside of the pipette will add to the blood in the pipette when the pipette tip is placed in the Unopette reservoir. This will increase and invalidate the cell count (falsely high). If the Unopette was not mixed before charging, then the count would most likely be low. Pulling blood out of the pipette when wiping away the excess on the outside will falsely lower the cell count because less blood will be present. Using a smaller volume pipette than required will lower the count, again because less blood will be present.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

More than 4.4billion prescriptions were dispensed within the United States in 2016.

Did you know?

People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.

Did you know?

About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.

Did you know?

Many supplement containers do not even contain what their labels say. There are many documented reports of products containing much less, or more, that what is listed on their labels. They may also contain undisclosed prescription drugs and even contaminants.

Did you know?

The strongest synthetic topical retinoid drug available, tazarotene, is used to treat sun-damaged skin, acne, and psoriasis.

For a complete list of videos, visit our video library