The cells in the following images all look very different. While cells can have different appearances and functions, they have the same basic structure.
Fig. 4 Plant cells
Fig. 5 Sperm cells
Fig. 6 Red and white blood cells
Fig. 7 Nerve cells
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Most cells have the following structures: Cell membrane: Holds the cell together. It controls what can enter and leave the cell. Cytoplasm: This is a watery, jelly-like fluid in which the other structures are suspended. Nucleus: Contains the information needed to keep a cell alive and working properly. It contains genetic information in the form of DNA. DNA is contained in structures called chromosomes. The nucleus controls cell activities. Small vacuole: Used for temporary storage of food and waste. Mitochondrion: Carries out a chemical reaction called respiration inside the cell. This reaction releases energy from glucose for various cellular activities.
Chromosomes Coiled threads of DNA and protein. Found in the nucleus of cells.
Respiration Chemical reaction that occurs in a cell to release energy from glucose.
