Unformatted text preview: SC121 Unit 4 Assignment SC121 Unit 4 Assignment
NAME: Van Edwards
DATE: 12/2/18 SC121 Unit 4 Assignment PART 1
1. Why are cells are important to the body
Cells are important because they execute many different functions that help the systems of
the body to achieve and maintain homeostasis (Tortora & Derrickson, 2017).
2. Which organelle do you think would kill you the fastest if you lost it? Explain your answer.
I believe that all organelles are important, and each serves its own function within a cell, but
I feel that losing the nucleus would kill you the fastest. The nucleus holds much of the DNA
in a cell and acts as the control center, controlling cellular structure and activity, as well as
producing ribosomes in nucleoli (Tortora & Derrickson, 2017). Without DNA the cell would not
be able to function. Genes are the instruction manual for life itself, as well as all life
3. How is cell shape related to function? Give at least 3 examples and explain.
Cell shape is directly linked to the function of that cell. Blood cells, for instance, are disc
shaped, with a large surface area. This increased surface area helps the blood cell to pass
oxygen to other cells. Sperm cells have a tail called the flagellum that is used to move the
cell around since sperm cells need to cover a significant distance. Nerve cells have axons
that extend out, allowing the nerve cell to cover greater distance which helps their function
of passing nerve impulses, while the smaller dendrites allow nerve cells to receive incoming
information (Tortora & Derrickson, 2017).
4. Choose one organelle or cellular component and research a disorder that affects it. Then,
answer the following:
● What is the name of the disorder?
● Which part of the cell is affected?
Cystic Fibrosis affects the endoplasmic reticulum of a cell.
● What are the consequences of this disorder?
Cystic fibrosis starts when a mutated form of a gene is passed on. The CF gene causes
the production of a defective protein called Cystic Fibrosis Transmembrane Conductance
Regulator (CFTR) which is a protein that gets stuck within the cells’ endoplasmic
reticulum. The endoplasmic reticulum is the site within a cell where certain proteins are
synthesized and transported. The CFTR protein causes the epithelial cells of the lungs to SC121 Unit 4 Assignment
have a thick, sticky mucus layer (F. Livingston, 2014). Bacteria and germs get caught in
this mucus and therefore cause chronic lung infections. SC121 Unit 4 Assignment PART 2
Name of tissue: Skeletal muscle tissue
Two characteristics used for identification: Striated fibers, cylindrical Question #2
Name of epithelium: Stratified cuboidal epithelium.
Discuss the classifications of epithelial tissue based on:
The stratified epithelium has multiple layers of cells, some of which are not connected to the
basement membrane. Shape
Cuboidal cells are cube shaped cells that are similar in size and shape.
How did this knowledge help you to identify the epithelium?
I knew that epithelium is classified by the shape of the cells as well as the layers of cells and
the arrangement of those layers. From looking at the image, I noticed that the cells are cube
shaped and have multiple layers, with one of the layers not attached to the basement
membrane. Question #3
Structure name: Nerve cell.
Identify each label:
A – Dendrite
B – Cell body
C – Axon SC121 Unit 4 Assignment
Direction of the nerve impulse: The dendrite receives a nerve impulse and passes it to the
nucleus in the cell body. The axon delivers the nerve impulse from the nucleus to where the
nucleus tells it to. Question #4
Name the tissue: Areolar connective tissue. List of all fibers present and function of each fiber
Elastic fibers form a fibrous network within connective tissue and give the connective tissue
the ability to stretch and retract without breaking (Tortora & Derrickson, 2017).
Collagen fibers are very strong but not rigid and create strength within connective tissue
letting it resist stretching, but still allowing flexibility (Tortora & Derrickson, 2017).
Reticular fibers are bundled up and have a layer of glycoprotein. They are very thin and
create networks. They give strength and support to connective tissue also (Tortora &
List 5 types of cells present and function for each cell Macrophages are a type of white blood cell that moves through tissue, grouping at sites of inflammation or infection to ingest bacteria and other material.
Plasma cells are commonly found in the gastrointestinal and respiratory tracts and secrete antibodies to get rid of foreign substances(Tortora & Derrickson, 2017).
Mast cells react to injury or infection by producing histamine. This causes blood vessels to dilate during the inflammatory process.
Fibroblasts travel through connective tissue secreting fibers and help to maintain structure of connective tissue.
Adipocytes store fats. They help to insulate and protect different parts of the body. SC121 Unit 4 Assignment
Tortora, G. J., Derrickson, B. H. (2017). Principles of Anatomy and Physiology, 15th Edition.
[Purdue University Global Bookshelf]. Retrieved from
F. Livingston, M.D. (2014). Cystic Fibrosis. Retrieved from
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- Spring '18
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