can someone help me with these calculations. I counted 60 cells in the picture 2

Question

can someone help me with these calculations. I counted 60 cells in the picture

2. Here is a sample of undiluted yeast cells on a hemocytometer. a) How many cells do you count? Ignore the ragged debris. (oo your work. 3. In your onion cells a) What are the average dimensions (width and height)? Remember your field width measurements b) Assuming the depth of the cell is 20 um, what is the volume of an average onion cell? c) I purchased an onion at Willies. It was spherical, with a diameter of 6cm. How many did I buy? d) That onion weighed 500g. What is the average weight of an onion cel?

Explanation / Answer

2a. As you mentioned, you counted 60 cells. we will use this to arrive at our solution for 2b.

2b. If you read the text and the principle behind hemocytometer, you will notice that the suare that we just counted (above) can hold only 4 nl  of the volume.

So, to get the actual density in cells per ml, we just have to scale up. I will explain you how.

1 nl =10-3 microliter (ul)= 10-6 milliliter (ml)

4 nl =4 x 10-3 microliter (ul)= 4 x 10-6 milliliter (ml)

4 x 10-6 ml have 60 yeast cells.

1 ml will have [60/(4 x 10-6) ] = 1.5 x 107 yeast cells/ ml

3a. 0.2mm x 0.2mm

3b.  As onion cells are rectangular cells, their volume can be calculated by ( width x height x depth)

given depth = 20 um= 20 x10-3 mm= 0.02mm

= 0.2mm x 0.2mm x 0.02 mm

=8 x 10-4 mm3

3c. It looks like part of the question c is missing. Please check the same.

3d. I looks like the answer for the 3d depends on 3c, please upload the 3c correctly. Check if any part is missing from the picture.

Please do let us know to help you with the questions.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.