Cell Structure and Function

1. Cell Structure and Function Unit 3 Section 2

2. Cell Overview • Basic unit of structure and function in living things = cell

3. Cell and Function • Obtaining oxygen, rid waste products, obtain food & growth

4. How the cell works • Each kind of cell structure has a different function within a cell

5. Enter into the Cell!! • Smaller structures inside the cell called organelles, carry out specific functions within the cell

6. Cell Wall • Nonliving material that surrounds the cells of plants and other organisms • Not in animal cells • Helps to protect and support cell • Made of cellulose – many materials can pass through

7. Cell Membrane • Forms outside boundary of cell – all cells • Separates cell from environment • Controls what substances come into and out of cell

8. Nucleus • Cells control center • Directs all cell’s activities

9. Nucleolus • Makes ribosomes – small grain-shaped organelles that produce proteins

10. Nuclear Envelope • Membrane that surrounds nucleus • Protects nucleus • Materials pass in and out of nucleus through pore on envelope

11. Chromatin • Thin strands of material that fill the nucleus • Contain information for directing a cell’s function.

12. Cytoplasm • Is a clear, thick, gel-like fluid • Fills region between cell membrane and nucleus • Moves constantly

13. Mitrochondria • Floats in cytoplasm • Rod-shaped • Powerhouse of the cell – converts energy stored into food energy

14. Endoplasmic Reticulum (ER) • Maze of passageways – network of membranes • Helps form proteins – from ribosomes • Ribosomes are attached to the ER & float in the cytoplasm

15. Ribosomes • Attach to surface of ER • Small grain-like bodies • Others float in cytoplasm • Function: factories to produce proteins • New made proteins released through wall of ER • Transported to Golgi Bodies

16. Golgi Bodies • Flattened sacs and tubes • Thought as the cells “warehouse” • Receive proteins & other materials formed from ER • Packs and distributes materials to other parts of cell to outside of cell

17. Vacuoles • Water-filled sacs floating in cytoplasm • Stores water, food, other materials needed for cell • Plants – one large central vacuole • Animal – many small • Can store waste products until removed

18. Lysosomes • Small round sac-like organelle • Contains chemicals that break down certain large food particles into small ones • Break down old cells, release substances to be used again • Cells recycling center

19. Cilia • Hair-like projections on some cell membranes Flagellum: •  a whip-like structure that allows a cell to move Both: • Provides locomotion or move liquids

20. Chloroplasts • Only plant cells – in the cytoplasm • Capture energy from sunlight and use it to produce food • Makes leaves green – where they are located

21. How Cells work together in an Organism • Multicellular: Made of many cells – often look different from one another and perform different functions Plants and animals included • Unicellular: Single cell organism

22. Specialized Cells • Multicellular organisms must carry out key functions – get oxygen, remain alive • Cells may specialize – perform specific functions that benefit the whole organism • One type of cell does one kind of job, while another does a different job

23. Examples of specialized cells • Red blood cells: • Carry oxygen to other cells and remove waste • Nerve cells: • Relay information to other cells in the body

24. Specialized cells (continued) • Differ in structure: • Each type has a distinct shape

25. Organization of Living Things • Level One (cont.) • Organisms that have many cells – multicellular – different cells have different jobs • All cells need the other cells to keep the organism alive

26. Level 2 • Tissue – a group of similar cells that perform the same function • Examples: in animals – blood, muscle, bone and nerve in plants – xylem (moves water) phloem ( moves food)

27. Level 3 • Organs – groups of different tissues working together to do a specific job Example: skin tissue, heart tissue, skeletal tissue

28. Level 4 • Organ systems –a group of organs that work together to perform a specific function or jobs • Example: Cardiovascular system, respiratory system

29. Level 5 • Organism – an entire living thing that can carry out all basic life functions

30. Single Celled organisms - Unicellular Level One: • Cell – the building blocks of living things (organisms) • They are free living and does all the jobs needed to keep organism alive