3The World of Cells1The NucleusIn the cells of organisms except bacteria, the hereditary material is in an organelle called the nucleus (NEW klee us).
4The Nucleus 1 Inside the nucleus are chromosomes (KROH muh zohmz). The World of Cells1The NucleusInside the nucleus are chromosomes (KROH muh zohmz).Chromosomes contain an important chemical called DNA. It determines which traits an organism will have.
5nucleus Controls all cell activities Has heredity information in chromosomes and DNA
6The World of Cells1Energy and the CellCells, except bacteria, have organelles called mitochondria (mi tuh KAHN dree uh).An important process called cellular respiration takes place inside a mitochondrion.
8The World of Cells1StorageIn cells, food, water, and other substances are stored in balloonlike organelles in the cytoplasm called vacuoles (VA kyuh wohlz).Some vacuoles store wastes until the cell is ready to get rid of them.
10The World of Cells1Inside the CellThe inside of a cell is filled with a gelatinlike substance called cytoplasm (SI tuh pla zum).Approximately two-thirds of the cytoplasm is water, but it also contains many chemicals that are needed by the cell.
11cytoplasmGel-like substanceHas water and important chemicals
13The World of Cells1Outside the CellThe cell membrane is a flexible structure that holds the cell together.The cell membrane forms a boundary between the cell and its environment.
14Cell membraneSurrounds cellControls what passes in and out of cell
15Nature's Solar Energy Factories The World of Cells1Nature's Solar Energy FactoriesMost photosynthesis in plants occurs in leaf cells.Inside these cells are green organelles called chloroplasts (KLOR uh plats).
16Nature's Solar Energy Factories The World of Cells1Nature's Solar Energy FactoriesAnimals obtain food from their surroundings.Plants, algae, and many types of bacteria make food through a process called photosynthesis (foh toh SIHN thuh sus).
17Nature's Solar Energy Factories The World of Cells1Nature's Solar Energy FactoriesDuring plant photosynthesis chloroplasts capture light energy and combine carbon dioxide from the air with water to make food.As the plant needs energy, its mitochondria release the food's energy.
18chloroplast Conducts photosynthesis Found mostly in leaf cells Contains chlorophyll-green color
19The World of Cells1Outside the CellSome cells also have a structure outside the cell membrane called a cell wall.The cell wall helps support and protect these cells.
20Cell wallProvides support and protectionPlant cell only
22The World of Cells1OrganellesExcept for bacterial cells, cells contain organelles (or guh NELZ).These specialized cell parts can move around in the cytoplasm and perform activities that are necessary for life.
23organelles Parts of the cell that have a specific job Inside the cell in the cytoplasm