Cell Structure & Function
Definition of Cell A cell is the smallest unit that is capable of performing life functions.
Examples of Cells Amoeba Proteus Plant Stem Red Blood Cell Nerve Cell Bacteria
“Typical” Animal Cell /~ acarpi/NSC/images/cell.gif
“Typical” Plant Cell
Cell Parts Organelles – inside the cell
1. Nucleus Controls cell processes – contains DNA 2. Nuclear Membrane Surrounds nucleus Made of two layers Provides support and protection for the nucleus
3. Chromatin In nucleus Made of DNA + Protein which gives us chromosomes. Contain instructions for traits & characteristics (looks like cooked spaghetti)
4. Nucleolus Inside nucleus Produces ribosomes for the cell (pink center in the drawing)
5.Nuclear Pores Holes which allow material to move into or out of the nucleus.
6.Cytoplasm Fluid-like mixture Supports the cell organelles.
Endoplasmic Reticulum 7.Smooth type (SER): lacks ribosomes. Contains enzymes to make lipids. 8.Rough type (RER) (pictured): ribosomes embedded in surface. Lipids and proteins are assembled for export from the cell.
9.Ribosomes Each cell contains thousands Make proteins Found on endoplasmic reticulum & floating throughout the cell VERY SMALL!!
10.Mitochondria Powerhouse of the cell Converts the energy in food to the energy that the cell can use (ATP).
11.Golgi Bodies Modify, sort and package protein.
12.Lysosome Contain enzymes to break down proteins, fats, and carbs. Garbage collector of the cell.
13. Vacuoles Membrane-bound sacs for storage, digestion, and waste removal Contains water solution Help plants maintain shape
14. Chloroplast Usually found in plant cells Converts sunlight into plant food. Where photosynthesis takes place
15.Centrioles Aid in cell division –only 2 in cell Only found in animal cells.
Cytoskeleton 16. Microtubules – maintain cell shape and help form the spindle in cell division. (hollow) 17. Microfilaments – aid in movement and support. (solid)
18. Cell Wall Provides support and protection for a plant cell. Found only in plants.
19. Cell membrane Regulates what enters and leaves a cell Provides protection and support for the cell