Question

A simplified model for an erythrocyte is a spherical capacitor with a positively charged liquid interior...

A simplified model for an erythrocyte is a spherical capacitor with a positively charged liquid interior of surface area A. The interior fluid is separated by a membrane of thickness b from the surrounding, negatively charged, plasma fluid. The potential difference across the membrane is 128 mV, and the thickness of the membrane is about 100 nm with a dielectric constant of κ = 5.1. Use 1.06 g/cm3 as the density of blood.

(a) Calculate the volume of the blood cell assuming that an average erythrocyte has a mass 1 ✕ 10−12 kg. From the volume determine the surface area of the erythrocyte (in m3).

volume________ m3

surface area________m3

(b) Calculate the capacitance of the blood cell. For this calculation, model the membrane as a parallel plate capacitor with the area found in part (a).

(c) Calculate the charge on the surface of the membrane (in m2). How many elementary charges does this represent?

volume_______ m3

surface area______ m2

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A model of a red blood cell portrays the cell as a spherical capacitor, a positively...
A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid by a membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness is estimated to be 99 nm and has a dielectric constant of 5.00. (a) If an average red blood cell has a...
A model of a red blood cell portrays the cell as a spherical capacitor, a positively...
A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid by a membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness is estimated to be 103 nm and has a dielectric constant of 5.00. (a) If an average red blood cell has a...
Let’s consider a spherical cell (it’s a simplified model) with conducting fluids inside and out and...
Let’s consider a spherical cell (it’s a simplified model) with conducting fluids inside and out and an insulating membrane in between. The capacitance of the cell membrane is 90 pF; the resistance across the membrane is 30 MΩ. Under normal circumstances, the potential inside the cell is 70 mV than the potential outside. An action potential is triggered if the motion of charges across the cell membrane changes this potential difference by 15 mV. 1) If the thickness of the...
1,The same voltage is applied between the plates of two different capacitors. When used with capacitor...
1,The same voltage is applied between the plates of two different capacitors. When used with capacitor A, this voltage causes the capacitor to store 15 μC of charge and 3.4 x 10-5 J of energy. When used with capacitor B, which has a capacitance of 7.9 μF, this voltage causes the capacitor to store a charge that has a magnitude of qB. Determine qB. 2,The membrane that surrounds a certain type of living cell has a surface area of 6.0...
Some cell walls in the human body have a layer of negative charge on the inside...
Some cell walls in the human body have a layer of negative charge on the inside surface and a layer of positive charge of equal magnitude on the outside surface. Suppose that the charge density on either surface is ± 0.50×10−3 C/m2, the cell wall is 5.1 nm thick, and the cell-wall material is air. Notes about Problem 18.77 and a Hint for Part D: The cell wall/membrane creates a separation of charge between the inside and outside of a...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT