The World of Cells 1 What are cells made of?

The World of Cells 1 Organelles

The World of Cells 1 The Nucleus In the cells of organisms except bacteria, the hereditary material is in an organelle called the nucleus (NEW klee us).

The Nucleus 1 Inside the nucleus are chromosomes (KROH muh zohmz). The World of Cells 1 The Nucleus Inside the nucleus are chromosomes (KROH muh zohmz). Chromosomes contain an important chemical called DNA. It determines which traits an organism will have.

nucleus Controls all cell activities Has heredity information in chromosomes and DNA

The World of Cells 1 Energy and the Cell Cells, except bacteria, have organelles called mitochondria (mi tuh KAHN dree uh). An important process called cellular respiration takes place inside a mitochondrion.

mitochondria Turns food into energy

The World of Cells 1 Storage In 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.

vacuole Storage Holds water and disposes wastes

The World of Cells 1 Inside the Cell The 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.

cytoplasm Gel-like substance Has water and important chemicals

chromosomes In nucleus has heredity information-DNA

The World of Cells 1 Outside the Cell The cell membrane is a flexible structure that holds the cell together. The cell membrane forms a boundary between the cell and its environment.

Cell membrane Surrounds cell Controls what passes in and out of cell

Nature's Solar Energy Factories The World of Cells 1 Nature's Solar Energy Factories Most photosynthesis in plants occurs in leaf cells. Inside these cells are green organelles called chloroplasts (KLOR uh plats).

Nature's Solar Energy Factories The World of Cells 1 Nature's Solar Energy Factories Animals obtain food from their surroundings. Plants, algae, and many types of bacteria make food through a process called photosynthesis (foh toh SIHN thuh sus).

Nature's Solar Energy Factories The World of Cells 1 Nature's Solar Energy Factories During 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.

chloroplast Conducts photosynthesis Found mostly in leaf cells Contains chlorophyll-green color

The World of Cells 1 Outside the Cell Some cells also have a structure outside the cell membrane called a cell wall. The cell wall helps support and protect these cells.

Cell wall Provides support and protection Plant cell only

Plant cells vs. animal cells Both cells

The World of Cells 1 Organelles Except 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.

organelles Parts of the cell that have a specific job Inside the cell in the cytoplasm

Organelles Not organelles