Presentation on theme: "Section 2: Looking Inside Cells"— Presentation transcript:
1 Section 2: Looking Inside Cells 7.1.b Students know the characteristics that distinguish plant cells, including chloroplasts and cell walls.7.1.c Students know that the nucleus is the repository for genetic information in plant and animal cells.
2 Enter the Cell Organelles- carry out specific functions within a cell Cell Wall- a stiff wall that surrounds the membrane giving the cell a rigid boxlike shapeKey concept: “The cell wall helps to protect and support the cell.”In plants the cell wall is made of celluloseCell wall is tough but some things can pass through like water and oxygenAnimal cells DO NOT have cell walls
3 Enter the CellAnimal cells have cytoskeleton- a protein “framework” inside the cell that gives the cell its shapeCell Membrane- forms a protective barrier between the cytoplasm and the environment outside the cell because an animal cell does not have a cell wallALL cells have cell membranesKey concept: “The cell membrane controls what substances come into and out of a cell.”To survive a cell must get food, oxygen, and as well as let out waste (like a window screen)
6 Sail on to the NucleusNucleus is surrounded by the nuclear envelope to protect the nucleusChromatin- thin strands floating in the cell that contains genetic material, instructions for directing the cells functionsNucleolus- where ribosomes are made
7 NucleusKey concept: “The nucleus is the cell’s control center, directing all of the cell’s activities.”
8 Organelles in the Cytoplasm Cytoplasm- a gel-like fluid that many different organelles are found inFluid in the cytoplasm is constantly movingKey concept: “In the cytoplasm are many organelles, including mitochondria, endoplasmic reticulum, ribosomes, Golgi bodies, chloroplasts, vacuoles, and lysosomes. Each of these organelles has specific functions in the cell.”
9 Organelles in the Cytoplasm Endoplasmic ReticulumMitochondria are known as the “powerhouses” of the cellThey convert energy in food molecules to energy the cell can use to carry out its functionsEndoplasmic Reticulum is similar to the system of hallways in a building.Proteins and other materials move throughout the cell using the endoplasmic reticulum.The spots on this organelle are ribosomes, which produce proteins.Mitochondria
10 Organelles in the Cytoplasm Golgi Body- receive proteins and other newly formed materials from the endoplasmic reticulum, package, and distribute them to other parts of the cell.Called the cells mailroomFlattened sacs and tubesGolgi BodyChloroplasts- capture energy from the sunlight and use it to produce food for the cellOnly in plant cells (and some other organisms)They are green in color giving the plant a green colorPlant cells
11 Organelles in the Cytoplasm Vacuole- stores water, food, waste, and other materialssome animal cells have vacuoles that store food, water, waste, and other materialslarge water filled sacksmost plant cells have oneRibosomes- small structures that function like factories to produce proteinsthey may float in the cytoplasm or be attached to the endoplasmic reticulum
12 Organelles in the Cytoplasm Lysosomes- small organelles that contain chemicals that breaks down food particles and worn-out cell partssmall round structuresthe “clean-up crew”
13 Cell DiversityNerve CellBlood CellKey Concept: “The variety of structure in cells reflects differences in cell function.”Some cells have certain organelles but not othersSome cells have more of one type of organellesCells come in different shapes
14 Looking BackWhat role do the cell wall and cell membrane play in the cell?What is the role of the nucleus in the cell?What organelles are found in the cytoplasm and what are their functions?How do cells differ?