Stem cells explained
By: Katherine Knies
In 1955, Rudolf Virchow, a German physiologist, discovered that cells come from preexisting cells in an organism. These types of cells were later to be called stem cells. Stem cells are cells that keep the ability to divide in the human body. These cells divide...
Biology class activity: Eukaryotic cell structure
By: Tami Port MS
This classroom activity can be used to familiarize students with basic cell structure and encourage them to think about how the membrane system of eukaryotes works. The exercise should be done after the class has been instructed in eukaryotic cell structure and function. Following the...
Prokaryotic Microbe Cell Biology
By: Tami Port MS
Prokaryotes are evolutionarily ancient, for billions of years the only form of life. Here's a summary of the basic "parts & pieces" of these primitive cells. Prokaryotes Pro = "before", karyon = "nucleus"Prokaryotes were the first type of cell to evolve, and unlike eukaryotic cells...
What are enzymes and what are they used for?
By: Helena Whyte
The school definition says that enzymes are biological catalysts. Enzymes are protein molecules. Enzymes increase the rate of reaction in a cell without the enzyme being used up. Enzymes increase the rate of only one type of biological reaction. Enzymes act on specific molecules. Researchers...
By: Tarek Musslimani
Eukaryotic cells differ than prokaryotic cells in that the latter do not possess nucleus while eukaryotes do possess nucleus. The structure of eukaryotes is comprised of a membrane which surrounds the cell in addition to organelles suspended inside the membrane. The organelles are suspended within...
What are prokaryotic and eukaryotic cells?
By: Jordan Baker - 543381
The foundation for life itself begins with the cell. The cell is the fundamental unit of structure and function in every living thing; however, there are two different types of cells. There are prokaryotic and eukaryotic cells. Prokaryotic cells are smaller and less complex...
By: Tarek Musslimani
The cells inside our body are in a continuous process of growing and dividing and differentiating during their life cycle. The extent of growing and maturating depend on the tissue that is involved. Growth under normal conditions in addition to mitosis and differentiation are all...
By: N. David
The cell is the basic unit of all life. For an organism to grow and reproduce, new cells must come into being. This happens through a process called cell division, wherein one cell becomes two or more cells. In prokaryotes, or simple organisms such as...
By: Perry McCarney
Cellular respiration refers to the transfer of oxygen and carbon dioxide across the cell membrane. The cell membrane is the outer layer of all cells within the body; the barrier enclosing every cell from it's surrounding tissue or fluid. While this transfer of gases is...
The structure and function of digestive cells
By: Mehtab Khan
Many of us, who have no specialized knowledge about biology or who have forgotten the minute details of how and where food travels, should read this article to find out. Biological research has advanced so far that we can see the tiny cells lining our...

 

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