Chapter and fungal spores out. During the first

Published by admin on

Chapter 3 Prokaryotes:

There were four scientists mentioned in this
presentation. The first in time is Antonie van Leeuwenhoek. Leeuwenhoek was the
first to see microbes and named them animalcules (which means small little
animals). He also made more than 250 microscopes that magnified with only one
lens. “He is called the Father of bacteriology and protozoology” (power point
presentation). The next scientist was Louis Pasteur who was the first to make
vaccines and develop a thorough understanding of fermentation. Pasteur is best
known for his disapproving the theory of spontaneous generation. He knew that
when food is left out it goes bad, but wanted to understand why. To do this he
made a flask called the swan flask, that had the ability to let air in but keep
bacterial and fungal spores out. During the first experiment, he boiled and
sterilized the flask. During the second experiment, he boiled the flask and
broke the neck. When observing the unbroken flask, he noticed had no presence
of microbes, while the broken flask had a presence of microbes because it had a
port of entry for the microbes. Joseph Lister was the first doctor who discovered
the cause of postsurgical infections. He purposed an aseptic technique in the
OR, which was composed of sterilizing surgical instruments with heat and
washing hands with chemicals. The last scientist mentioned was Robert Koch.

Koch was responsible for many things the main being developing a culturing
method, and developing a theory that a specific pathogen caused a specific disease
which is known as Koch’s postulates.

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

Everything that is living is made up of a single
cell or several cells (multicellular). All cells have four features. The first
feature is the plasma membrane, which is the protective barrier that separates
cells. Second is the cytoplasm which is the inside the cell. Third are the
ribosomes which make protein to keep the cell alive and thriving. Fourth is the
DNA. Cells need DNA to reproduce because it is also the material that is passed
onto another cell.

Prokaryotic cells all lack a nucleus and are
unicellular. They also have a plasma membrane, cytoplasm, DNA, ribosomes and
most Prokaryotic cells also have a cell wall. Some Prokaryotic cells have
flagella, which provides the cell with motility. Pili are often shorter than
flagella and help the cell attach to a host. Fimbriae are also shorter than
flagella and can attach to hosts as well as attach to other cells. The capsule
is the outermost layer of the cell.

There are three different osmolarities. When a
solution is Isotonic it means the concentration of solutes are the same outside
as they are inside the cell.  A
Hypertonic solution is when the concentration of the solute is higher outside
of the cell than it is inside the cell. A hypotonic solution means the concentration
of the solute is lower outside of the cell. Plant cells always have a cell wall
so even if the plant is placed in a hypotonic solution the cell wall will not
lysis (burst). If a plant cell was placed in a hypertonic solution the cell
would crenate (shrink) due to the higher concentration outside of the cell. If
the cell did not have a cell membrane and was placed in a hypertonic solution
with a higher concentration the cell would crenate. If the cell without a cell
membrane was placed in a hypotonic solution with lower concentration the cell
would increase in size until it lysis. If a cell with or without a cell
membrane was placed in an isotonic solution there would be no movement of the
particles because the cell would be satisfied with the osmolarities.

Categories: Articles


I'm Iren!

Would you like to get a custom essay? How about receiving a customized one?

Check it out