Cell Functions Mrs. Reed

Cell Diversity What you have studied is an average human cell Trillions of cells in body 200 cell types (different sizes, shapes, and function)

Shape relates to Function The shape of human cells and the relative abundances of their various organelles relate to their function in the body. We will look at a few…

1. Cells that connect body parts Fibroblast Elongated shape Secretes fibers Many rough ER Large Golgi Apparatus

1. Cells that connect body parts Erythrocyte (red blood cell) Carries oxygen in the bloodstream Concave disc shape (extra surface area to take up oxygen and flows easily through bloodstream) No organelles because it needs room for its oxygen-carrying pigment

2. Cells that covers and lines body organs Epithelial cells Hexagonal shape (like the “cell” of a beehive) Allows the cell to pack together in sheets Many intermediate filaments to resist tearing

3. Cells that move organs and body parts Skeletal Muscle AND Smooth Muscle Cells Elongated Filled with contractile filaments Shorten to move bones or change size of internal organs

4. Cells that store nutrients Fat Cell (lipocyte) Huge spherical shape Produced by a large lipid droplet in its cytoplasm

5. Cells that fight disease Macrophage (a phagocytic cell) Uses long pseudopods (“false feet”) to crawl through tissue to reach infection sites. Many lysosomes are needed to digest the infectious organisms it engulfs

6. Cell that gathers information and controls body functions Nerve cell (neuron) Long processes to receive and transmit messages Extensive plasma membrane Lots of rough ER to make membrane components

7. Cells of reproduction Oocyte (female) Largest cell in body Contains many of copies of all organelles To give to daughter cells when the fertilized egg divides to become an embryo Sperm (male) Long (built for swimming to the egg for fertilization) Flagellum acts like a motile whip to propel the sperm