Objectives for today:
• Differentiate between fibrous and globular proteins.
• Compare and contrast the structure and functions of DNA and RNA.
The smallest
known living thing on Earth is a bacteria in the genus Coxiella. These
bacteria are about 8 millionths of an inch (0.2 micrometers) in diameter.
Their small size means these bacteria contain only 100 million to 120
million atoms. It is believed that fewer atoms would be unable to build
the structures needed to store information and carry out the metabolic
processes needed for life.
Coxiella is a very small
cell and it contains about 120 million atoms. Animal cells are much larger
and the human body has over 5 Billion of them.
The largest known animal
is the blue whale, Balaenoptera musculus. It is known to reach lengths
over 100 feet (30+ meters) and weigh 120 tons. Even though it is the largest
of animals, it feeds on microscopic organisms.
This chart indicates that
all animal cells are about 10 micrometers in diameter. This means that
the cells of a blue whale and a human are essentially the same size. The
whale just has many more.
Calculate the surface area and volume of each to 2 significant digits
.
* Show how you set up the following calculations
on your paper.
* Use 3.1 for in these calculations.
* The formula for calculating the surface area of a sphere issurface area = 4
r ˆ2
* The formula for calculating the volume of a sphere is
V = 4/3
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