Question

Bacteria vary somewhat in size, but a diameter of 2.9 μm is not unusual.

A) What would be the volume (in cubic centimeters) of such a bacterium, assuming that it is spherical?
B) What would be the surface area (in square millimeters) of such a bacterium, assuming that it is spherical?

Answer 1

See below

Step-by-step explanation:

Volume of a sphere = 4/3 pi r^3

we are given diameter r = 1/2 dia = 1.45 u-meter = 1.45 x 10^-4 cm

4/3 pi (1.45 x 10^-4)^3 = 1.277 x 10^-11 cm^3 = VOLUME

1.45 u-meter = .00145 mm

Surface area = 4 pi r^2 = 4 pi (1.45 x 10^-3 ) ^2 = 2.64 x 10^-5 mm^2

Answer 2

a) 6.4 x 10^-12 cm^3

b) 17 x 10^-6 mm^2

Explanation

a). The shape is assumed to be spherical The volume = volume of a sphere = \frac{4}{3} \pi r^3

3

4

πr

3

V = \frac{4}{3}*3.142* 1.15^3

3

4

∗3.142∗1.15

3

= 6.3715 μm^3

1 μm^3 = 10^-12 cm^3

6.3715 μm^3 = 6.3715 x 10^-12 cm^3

==> 6.4 x 10^-12 cm^3