Basic Structure of a Cell

1. Basic Structure of a Cell

2. Introduction to Cells Cells are the basic units of organisms Cells can only be observed under microscope Basic types of cells: Bacterial Cell Animal Cell Plant Cell

3. The Cell Theory • All living things are composed of cells. • Cells are the basic units of structure and function in living things. • New cells are produced from pre-existing cells.

4. Number of Cells • Organisms may be: • Unicellular – composed of one cell • Multicellular- composed of many cells that may organize

5. Cells May be Prokaryotic or Eukaryotic • Prokaryotes include bacteria & lack a nucleus or membrane-bound structures called organelles • Eukaryotes include most other cells & have a nucleus and membrane-bound organelles (plants, fungi, & animals)

6. Prokaryotes • Nucleoid region contains the DNA • Cell membrane & cell wall • Contain ribosomes (no membrane) to make proteinsin their cytoplasm

7. Contain 3 basic cell structures: Nucleus Cell Membrane Cytoplasm with organelles Eukaryotic Cell

8. Two Main Types of Eukaryotic Cells Animal Cell Plant Cell

9. Organelles Very small size Can only be observed under a microscope Have specific functions Found throughout cytoplasm

10. Organelles Found in Cells Examples of Organelles include: Endoplasmic reticulum (rough & smooth) – canals for movement Golgi Bodies – wrap & export proteins Nucleolus – makes ribosomes Lysosomes – digests & gets rid of wastes Ribosomes – makes proteins

11. Golgi Bodies • Stacks of flattened sacs • Have a shipping side & a receiving side; • Packaging center of the cell. Transport vesicle

12. Lysosome • Contain digestive enzymes • Break down food and worn out cell parts for cells

13. Nucleolus • Cell may have 1 to 3 nucleoli • Inside nucleus • Makes ribosomes that make proteins

14. Smooth & Rough Endoplasmic Reticulum Smooth ER lacks ribosomes & makes proteins USED In the cell Rough ER has ribosomes on its surface & makes proteins to EXPORT

15. Mitochondrion( mitochondria ) Cell Powerhouse • Rod shape • Site of Cellular respiration

16. In Animal Cells: Mitochondria • Active cells like muscles have more mitochondria

17. Cell membrane Surrounding the Cell • Lies immediately against the cell wall in plant cells • Made of protein and phospholipids • Selectively permeable

18. Cell or Plasma Membrane Cell membrane • Living layer • Controls the movement of materials into and out of the cell • Selectively permeable

19. Cell Wall Cell wall • Nonliving layer • Gives structure and shape to plant and bacterial cells.

20. Cytoplasm Cytoplasm of a Cell • Jelly-like substance enclosed by cell membrane. • Contains organelles to carry out specific jobs

21. Nucleus Control Organelle • Control center of the cell; • Contain the DNA • Bounded by a nuclear membrane • Contains chromosomes

22. Chloroplast Plant Cell Organelles • Contain the green pigment chlorophyll; • Traps sunlight to make sugars (food); • Process called photosynthesis

23. Plant Cell Cell wall • Protect and support the enclosed substances (protoplasm); • Give shape to the cell

24. Vacuole Plant Cell Organelles • Have a large central vacuole; • Contains cell sap • Sugars, proteins, minerals, wastes, & pigments

25. Onion Epidermal Cells Guard Cells root hair Root Hair Cell Different kinds of plant cells

26. Animal cell vacuole cytoplasm No cell wall or chloroplast Stores glycogen in the cytoplasm for food energy nucleus mitochondrion cell membrane glycogen granule

27. Near the nucleus Paired structures Help cell divide Animal Cell Organelles

28. white blood cell Amoeba red blood cell muscle cell sperm cheek cells nerve cell Paramecium Different kinds of animal cells

29. Similarities between plant cells and animal cells Both have a cell membrane surrounding the cytoplasm Both have a nucleus Both contain mitochondria

30. Differences between plant cells and animal cells Animal cells Plant cells Relatively smaller in size Relatively larger in size Irregular shape Regular shape No cell wall Cell wall present

31. Differences between Plant Cells and Animal Cells Animal cells Plant cells Vacuole small or absent Large central vacuole Glycogen as food storage Starch as food storage Nucleus at the center Nucleus near cell wall

32. Compound Microscope • Instrument for observing small objects • Magnify images up to 2000X their size

33. Different parts of a microscope

34. Revolving nosepiece Eyepiece Body tube Objective Coarse adjustment Clip Fine adjustment Condenser Arm Stage Iris diaphragm Condenser control knob Mirror Base

35. Levels of organization • Cells are grouped together and work as a whole to perform special functions

36. Tissue • A group of similar cells to perform a particular function • Animals : epithelial tissue, muscular tissue • Plants :vascular tissue, mesophyll

37. Organ • Different tissues group together to carry out specialized functions • Heart :consists of muscles, nervous tissue and blood vessels • Leaf :consists of epidermis, mesophyll and vascular tissue

38. The Structures of a Leaf (Plant Organ) Chloroplast Palisade Mesophyll Cell Spongy Mesophyll Cell Air Space Stoma

39. The Structures of a Heart (Animal Organ)

40. System • Several organs and tissues work together to carry out a particular set of functions in a co-ordinated way • Human :digestive, respiratory, excretory, circulatory and reproductive systems • Plant :root and shoot systems

41. Human Body Systems Examples of systems : • Digestive System • Respiratory System • Circulatory System • Nervous System • Reproductive System

42. Examples of a Human Body System

43. Examples of a Human Body System

44. Examples of a Human Body System Circulatory System

45. Examples of a Human Body System Nervous System

46. Levels of Organization • CELLS (muscle cells,nerve cells) • TISSUES (muscle, epithelium) • ORGANS (heart, lungs, stomach) • SYSTEMS (circulatory system) • ORGANISM (human)

47. It’s You!