1. 1.2 Eukaryotic Cells
IB HL Biology

2. Essential Idea
Eukaryotes have much more complex cell structures than prokaryotes

3. Eukaryotic Cells
Algae
Fungi
Plants
Animals

4. Eukaryotic Properties
More complicated than prokaryotic
Nucleus with a nuclear membrane
Many membrane-bound organelles with distinct functions m

5. Eukaryotic Cell Structure
Nucleus – double membrane control centre
Store DNA chromosomes in form of chromatin
DNA replication and transcription
Nucleolus – in the nucleus
Made of RNA
Makes ribosomes

6. Eukaryotic Cell Structure
Ribosomes
Ribosomes – link amino acids into proteins like enzymes
Made in the nucleolus
Made of RNA and protein
~ 20nm
Size = 80s

7. Eukaryotic Cell Structure
Endoplasmic Reticulum-Folded membrane that carries materials through cytoplasm
Make proteins for secretion to outside the cell
Rough ER (rER)
Covered in ribosomes
Makes proteins
Smooth ER (sER)
No ribosomes
Synthesize fats and lipids

8. Eukaryotic Cell Structure
Golgi apparatus – folded membrane for storing, processing and packaging proteins from rER
Create vesicles (small sac)
Exocytosis - sac fuses with cell membrane and empties contents outside of cell
Mitochondria – double membrane with enzymes on cristae (folds)
Inside called matrix
Produce large amount of ATP for cell by cell respiration
Power plant of cell
What kind of cell would have lots of mitochondria? Why?

9. Lysosome Created by Golgi Apparatus
Vesicle filled with hydrolytic enzymes
Breakdown and recycle cell parts and biomolecules

10. Eukaryotic Cell Micrographs
Mitochondrion
Golgi apparatus
Nucleus
Lysosome

11. Liver Cell Micrographs
Rough ER
Mitochondrion
Free ribosome

12. Liver Cell Micrographs
Mitochondrion
Rough ER
Cell membrane
Nucleus

13. 2.3.1 Draw and label a diagram of the ultra structure of the liver as an example of an animal cell

14. Differences between Prokaryotic and Eukaryotic Cells
Prokaryotes
Smaller
Single, circular DNA
DNA in cytoplasm (no nucleus)
Small ribosomes (70S)
Usually no extra membranes: no mitochondria, ER, golgi, chloroplasts, vacuole, etc.
Eukaryotes
Larger, containing multiple mitochondria
Multiple strings of DNA organized by proteins
DNA in nuclear membrane
Large ribosomes (80S)
Many extra membranes forming compartments for special jobs for many organelles

15. Plant & Animal Cells

17. Animal Cell

18. Plant and animal cell differences
Cell wall (cellulose)
For structure, support and regular shape.
No cell wall
Large central vacuole
May have small temporary vacuoles
Autotrophs
Heterotrophs
Chloroplast - photosynthesis
No chloroplast
Carbs stored as starch
Carbs stored as glycogen (some fat)
No centrioles
Centrioles (mitosis)

19. Structures outside the cell: Cell wall of plants
Primary cell wall
Non-living
Cell wall is made of cellulose (carbohydrate)
Cellulose makes microfibril bundles with other molecules
Supports
Cell shape
Overall plant shape (opposes gravity)
Storage of carbohydrates
Prevents the cell from absorbing too much water and bursting (lysis) 19

20. Structures outside the cell: Animal Extracellular Matrix
Glycoproteins
proteoglycan
Plays a role in
Support
Adhesion
Movement
Helps in embryonic development 20

21. IB Objectives Eukaryotes have a compartmentalized cell structure.
Skill: Drawing of the ultrastructure of eukaryotic cells based on electron micrographs
Skill: Interpretation of electron micrographs to identify organelles and deduce the function of specialized cells.

22. Task:
Venn Diagram of prokaryotic and eukaryotic cells