Cell Structure -Describe the structure and function of the cell nucleus. -Describe the roles of the organelles. -Describe the function of the cell membrane.

Lesson Overview Lesson Overview Cell Structure Cell Organization Many cellular structures act as if they are specialized organs. These structures are known as organelles or “little organs.”

Lesson Overview Lesson Overview Cell Structure The Nucleus The nucleus is the control center of the cell. The nucleus contains nearly all the cell’s DNA.

Lesson Overview Lesson Overview Cell Structure Vacuoles Many cells contain structures called vacuoles that store water, salts, proteins and carbohydrates. Animal cells store carbohydrates in the form of glycogen. Plant cells store carbohydrates in the form of starch.

Lesson Overview Lesson Overview Cell Structure Lysosomes Lysosomes are small organelles filled with digestive enzymes that function as the cell’s cleanup crew.

Lesson Overview Lesson Overview Cell Structure The Cytoskeleton Eukaryotic cells are given their shape and internal organization by a network of protein filaments known as the cytoskeleton.

Lesson Overview Lesson Overview Cell Structure Cilia and Flagella Cilia and Flagella aid in movement. Cilia allow movement of the cell, as well as, substances around a cell, like mucus in the Respiratory System. Flagella allow movement of the cell itself, such as with sperm.

Lesson Overview Lesson Overview Cell Structure Ribosomes Ribosomes produce proteins, some are found in the cytoplasm others are attached to the rough ER.

Lesson Overview Lesson Overview Cell Structure Endoplasmic Reticulum (ER) The rough endoplasmic reticulum, or rough ER, is involved in the synthesis of proteins. The smooth endoplasmic reticulum, or smooth ER, has no ribosomes on its surface. The smooth ER is involved in the synthesis of membrane lipids and detoxification of drugs.

Lesson Overview Lesson Overview Cell Structure The Golgi apparatus modifies, sorts and packages proteins and other materials from the ER for storage in the cell or release outside the cell. It is like the UPS of the cell, where items are packaged and shipped. Golgi Apparatus

Lesson Overview Lesson Overview Cell Structure Chloroplasts Plants and other photosynthetic organisms contain chloroplasts. Chloroplasts are the biological equivalents of solar panels. They capture the energy from sunlight and convert it into energy in a process called photosynthesis.

Lesson Overview Lesson Overview Cell Structure Mitochondria Nearly all eukaryotic cells, including plants, contain mitochondria. Mitochondria are the power house of the cell. They convert the chemical energy stored in food into ATP (ENERGY!). The mitochondria is also unique because it has its own DNA, which came from the ovum, or egg, and therefore came directly from your MOM!

Lesson Overview Lesson Overview Cell Structure Centrosome (aka Centrioles) An organelle that lies close to the nucleus in ANIMAL CELLS ONLY. This tiny organelle is involved in nuclear division.

Lesson Overview Lesson Overview Cell Structure Cellular Boundaries Cells are surrounded by a barrier known as the cell membrane. Many cells, including most prokaryotes, also produce a strong supporting layer around the membrane known as a cell wall.

Lesson Overview Lesson Overview Cell Structure Cell Walls The main function of the cell wall is to provide support and protection for the cell. Prokaryotes, plants, algae, fungi have them. Animal cells do not have cell walls.

Lesson Overview Lesson Overview Cell Structure Cell Membranes All cells contain a cell membrane that regulates what enters and leaves the cell and also protects and supports the cell. The composition of nearly all cell membranes is a double-layered sheet called a lipid bilayer. The cell membrane is selectively permeable (only let’s certain things in).

Lesson Overview Lesson Overview Cell Structure The Cell Membrane (aka Phospholipid Bilayer The fatty acid portions of such a lipid are hydrophobic, or “water-hating,” while the opposite end of the molecule is hydrophilic, or “water-loving.”