The Cell
Essay by review • November 26, 2010 • Essay • 750 Words (3 Pages) • 1,160 Views
The Cell
It was the first day of elementary science class. The students were seated and eager to learn about the wonders of a the cell. "Good morning class, my name is Mrs. White and I will be your science teacher." All of the students seemed excited to learn about the parts of the cell, except for one. Her name was Ashley, she didn't understand why you need to learn about a cell, when you needed a microscope to see one. Ashley thought that cells were unimportant and didn't serve any purpose. But, her attitude will soon change.
Mrs. White drew a picture of a cell on the chalk board and labeled each of the parts. She then began to tell what a cell is. "A cell is the basic unit of all forms of life" said Mrs. White. First there is the cell membrane which is a thin flexible barrier around the cell. The cell wall is a strong layer around the cell membrane. "So the cell wall is like the outer wall of your house" said Ashley. "you are correct" said Mrs. White. Some cells also have a nucleus. This is a large structure that contains a cells genetic materials and controls the cells activities. Inside the nucleus is the nucleolus. Johnny asked "What is the nucleolus function?" "Well , Johnny for many years the function of the nucleolus was a mystery. Scientist now know, that this is where the assembly of ribosomes begins." The ribosomes aid in the production of protein in the cell. The endoplasmic reticulum is the organelle in which components of the cell membrane in some proteins are modified. Mrs. White asked "what are the two types of endoplasmic reticulum?" Ashley raised her hand and said "rough and smooth." The rough endoplasmic reticulum is involved in the synthesis of proteins. It gets its name because o the ribosomes that stud its surface. Newly made proteins move directly from these ribosomes into the rough endoplasmic reticulum where the become chemically modified. The smooth endoplasmic reticulum contains collections of enzymes that perform specialized tasks, such as the synthesis of lipids. "Wow! I can't believe that the smooth and rough endoplasmic reticulums had such interesting jobs" said Ashley. Mrs. White then went on to explain that these proteins produced by the rough endoplasmic retculum moves into a stack o membranes called the golgi apparatus. "What happens to the proteins once they reach the golgi apparatus?" asked Judy. "The enzymes in the golgi apparatus attach carbohydrates and lipids to the proteins" replied Mrs. White. Lysosomes are small organelles filled with enzymes. One function of the lysosomes is to break down lipids, carbohydrates, and proteins from food into particles that can be used by the rest of the cell. They also help break down organelles that have outlived their usefulness. "This is an
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