Modeling Cell Size

Steve Harris

SPASH - Biology

Cell SizeA.) 1cm x 1cm x 1cmB.) 2cm x 2cm x 2cmC.) 4cm x 4cm x 4cm

Group #DateHour

Group #DateHour

Glue TabsDot Dot

Just a Drop!Or

Dot Dot DotNot a Lot!

Dot DotDon’t Need a

Lot!Or

Dot Dot DotDon’t eat a Lot!

SA=6S 2 V=lxwxh

CellDimemsions

(cm)Surface Area

(cm2) Volume (cm3)

Ratio Surface Area :

Volume

A

B

C

Sample 5cmx5cmx5cm

SA= 6(5cm) 2

SA=150cm 2

V=5cmx5cmx5cm

V=125cm 3

150:125

1.2 : 1

Like This!!1. Formula2. Sub. W/Units3. Answer w/Units

1 1

2

3

2

3

SA=6S 2 V=lxwxh

CellDimemsions

(cm)Surface Area

(cm2) Volume (cm3)

Ratio Surface Area :

Volume

A 1cmx1cmx1cmSA=6(1cm) 2

SA=6cm 2

v=1cmx1cmx1cm v=1cm 3 6:1

B 2cmx2cx2cmSA=6(2cm) 2

SA=24cm 2

v=2cmx2cmx2cm v=8cm 3 3:1

C 4cmx4cmx4cmSA=6(4cm) 2

SA=96cm 2

v=4cmx4cmx4cm v=64cm 3 1.5:1

Sample 5cmx5cmx5cm

SA= 6(5cm) 2

SA=150cm 2

V=5cmx5cmx5cm

V=125cm 3

150:125

1.2 : 1

CHECK YOUR WORK

What are the largest & smallest Cells in the human body?

• The human ovum is typically around 120um and yes, it is visible to the human eye. The Anterior Horn Cell of the spine however, is around 135um thus making it the largest in circumference. One micron is one-thousandth of a millimeter.

• The smallest cell is not the human sperm. The human sperm including flagellum (tail) is approximately 25um. The head of the sperm is on average 5um-6um. The Granule Cell of the Cerebellum is typically 4um - 4.5um thus making is smaller than the human sperm.

• Typically the RBC (Red Blood Cell or Red Blood Corpuscle to be exact) is used as the standard measurement for cell size in the human body. Normal RBC size typically ranges from 4.5um - 8.5um.