1. Cell Structure and Function

2. Cells Smallest living unit Most are microscopic

3. Cell Size

4. Cells Have Large Surface Area-to-Volume Ratio

5. Characteristics of All Cells Cell Membrane (Plasma Membrane) Cytoplasm – cell contents in thick fluid Control center with DNA

6. Cell Types Prokaryotic Eukaryotic

7. Prokaryotic Cells First cell type on earth Cell type of Bacteria and Archaea

8. Prokaryotic Cells No membrane bound nucleus Nucleoid = region of DNA concentration Organelles not bound by membranes

9. Eukaryotic Cells Nucleus bound by membrane Include fungi, protists, plant, and animal cells Possess many organelles Protozoan

10. Representative Animal Cell

11. Representative Plant Cell

12. Cytoplasm Viscous fluid containing organelles components of cytoplasm –Interconnected filaments & fibers –Fluid = cytosol –Organelles (not nucleus) – storage substances

13. Nucleus Double membrane filled with nucleoplasm Control center of cell Houses and protects cell’s genetic info Control’s cells functions

14. DNA Hereditary material Chromosomes –DNA and protein –Only visible when cell is dividing (but present all the time)

15. Nuclear Envelope and Pores Double membrane Separates nucleus from rest of cell Has pores Allows only certain materials to enter and exit nucleus

16. Nucleolus Dark dense area inside nucleus Where DNA is concentrated when making ribosomal RNA

17. Cell (Plasma) Membrane Double layer of phospholipids, proteins and cholesterol Contains cell contents Controls what enters/exits the cell

18. Endoplasmic Reticulum Helps move substances within cells Network of interconnected membranes Two types –Rough endoplasmic reticulum –Smooth endoplasmic reticulum

19. Rough Endoplasmic Reticulum Ribosomes attached to surface Helps to move proteins around cell May modify proteins from ribosomes

20. Smooth Endoplasmic Reticulum No attached ribosomes Helps to make lipids Detoxifies and breaks down harmful chemicals

22. Ribosomes Attached to ER or free floating in cytoplasm

23. Golgi Apparatus Stack of flattened membranes Packaging & shipping station of cell Proteins go here after leaving ER and are modified and shipped out of cell in small sacs called vesicles

25. Lysosomes Small sac-like structures Contain digestive enzymes Functions –Recycling centers –Break down old cell parts –Digests invaders Found in animal cells

26. Peroxisomes Small sac-like structures Abundantly found in liver and kidneys Help to detoxify Names for the hydrogen peroxide they produce as a waste from their reactions.

27. Mitochondria Break down sugars and fats in cellular respiration and release energy in the form of ATP Cells that need more energy have more

28. Mitochondria Has its own DNA (endosymbiotic theory)

29. Cytoskeleton Filaments & fibers –Microfilaments –Microtubules –Intermediate filaments 3 functions: – mechanical support – anchor organelles – help move substances Include cilia, flagella and centrioles

31. Centrioles Pairs of microtubular structures Play a role in cell division Found only in animal cells

32. Cell Walls Found in plants – composed of cellulose Surrounds plasma membrane Provides support, strength and protection

33. Central Vacuoles Membrane bound storage sacs In plants Very large Contents –Water –Food –Wastes *animals have small vacuoles throughout cell

34. Chloroplasts Solar energy capturing organelle – carry out photosynthesis Contain chlorophyll and are green Have their own DNA

35. Chromoplast Contain pigments Help capture more light energy for photosynthesis Help to make other parts of the plants other colors (fruits, flowers, roots etc.)

37. End Chapter 5