1. TOPIC 1.2 – CELL ULTRASTRUCTURES

3. 1.2 – A - Prokaryotes

4. IB BIO – 1.2
Cells can be divided into categories based on their structures and complexity. The categories discussed in this topic are:
Prokaryotes
Eukaryotes 4
INTRO

5. IB BIO – 1.2
Prokaryotes are cells whose genetic material is not contained within a nucleus and who have a simple structure.
They were the first life forms and do not have compartmentalized organelles. 5
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Key Terms

6. IB BIO – 1.2
Unlike eukaryotes, prokaryotes divide through a process called binary fission.
It is a type of asexual reproduction where the cell duplicates its genetic material before splitting its DNA and cytoplasm in half. The daughter cells are identical. 6
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Applications
A2: Prokaryotes divide by binary fission.
Key Terms
Binary Fission

7. Prokaryotic Structures
IB BIO – 1.2
Prokaryotic Structures 7
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Applications
A2: Prokaryotes divide by binary fission.
Cell membrane - surrounds the cell and controls what travels in and out. It separates the cell from the environment.
Cytoplasm - the liquid contents within the cell membrane. It is the site of metabolic reactions.
Cell wall - located outside of the membrane. It provides structural support to the cells.
Key Terms
Cell Membrane
Cytoplasm
Cell Wall

8. Prokaryotic Structures
IB BIO – 1.2
Prokaryotic Structures 8
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Applications
A2: Prokaryotes divide by binary fission.
Ribosomes – site of protein synthesis
Nucleoid – region containing the naked DNA. This means it is not associated with any proteins.
Key Terms
Ribosomes
Nucleoid

9. Prokaryotic Structures
IB BIO – 1.2
Prokaryotic Structures 9
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Applications
A2: Prokaryotes divide by binary fission.
Cilia – hair-like structures that assist in mobility as well as moving extracellular materials
Flagella – long whip-like structures that is used as a ‘motor’ for movement
Key Terms
Cilia
Flagella

10. IB BIO – 1.2
Because prokaryotic cells are so small, light microscopes cannot be used to observe them.
Electron microscopes use electron beams to visualize small samples and so have a much higher resolution.
They can produce images like those to the left, which can be used to study prokaryotic structures 10
Understandings
U3: Electron microscopes have a much higher resolution than light microscopes.
Key Terms
Electron Microscope

11. 1.2 – B – Eukaryotes

12. IB BIO – 1.2
Prokaryotes are simple organisms and were the original life forms on Earth. Over time, they eukaryotes evolved from them. 12
INTRO

13. IB BIO – 1.2
Eukaryotes are organisms that are complex and that have compartmentalized structures called organelles. Most notably, their DNA is contained within a nucleus. Eukaryotic organelles include… 13
Understandings
U2: Eukaryotes have a compartmentalized cell structure.
Key Terms
Eukaryotes

14. IB BIO – 1.2 14
The nucleus contains the cells genetic information in the form of chromosomes. It is surrounded by a double membrane and is the site of DNA replication and transcription.
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
The cell membrane is a phospholipid bilayer that surrounds the cell. It controls what diffuses in/out and contains embeddd proteins that serve many functions.
Key Terms
Nucleus
Cell Membrane

15. Rough Endoplasmic Reticulum
IB BIO – 1.2
Ribosomes are the site of protein synthesis.
The rough endoplasmic reticulum has ribosomes on its outer surface. Its role is to package proteins for secretion. It sends them in vesicles to the Golgi apparatus. 15
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms
Ribosomes
Rough Endoplasmic Reticulum

16. IB BIO – 1.2
Vesicles are small sacs made of membrane that are used to transport materials within the cell.
The Golgi apparatus processes proteins that are received from the rough ER. Then it sends them in vesicles to the cell membrane. 16
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms
Vesicles
Golgi Apparatus

17. IB BIO – 1.2
Together, the rough ER, Golgi apparatus and vesicles play a key role in moving materials in/out of the cell through the cell membrane. 17
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms

18. IB BIO – 1.2
The mitochondrion is responsible for producing energy in the form of ATP. It does so through cell respiration.
Often called the ‘power house’ of the cell. 18
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
The chloroplast is responsible for photosynthesis, which converts light energy into chemical energy.
It is only found in autotrophic organisms, which includes plant cells.
Key Terms
Mitochondrion
Chloroplast

19. IB BIO – 1.2
Microtubules are fibers that play an important role in moving chromsomes during cell division. 19
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms
Microtubules
Centrioles
In animal cells, microtubules are anchored at structurs called centrioles.

20. IB BIO – 1.2
Vacuoles are similar to vesicles in they are made of phospholipid bilayers. Their role is to store water and can be quite large in plants, which provides structural support. 20
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms
Vacuole

21. IB BIO – 1.2
The cell wall is a rigid structure that is found outside the cell membrane in plant cells. Just like in prokaryotes, it provides structural support.
In plants, large vacuoles push against the cell wall which creates internal pressure. This allows plants to stand upright. 21
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms
Cell Wall

22. IB BIO – 1.2
The primary differences between animal and plant cells are:
Plant cells contain chlorosplasts
Plant cells have large vacuoles
Plant cells have cell walls 22
Applications
A1: Structure and function of organelles within exocrine gland cells of the pancreas and within palisade mesophyll cells of the leaf.
Key Terms

23. Identify the name and function of the following organelles
IB BIO – 1.2
Identify the name and function of the following organelles 23
REVIEW

24. Identify the organelles in the plant cell below
IB BIO – 1.2
Identify the organelles in the plant cell below 24
REVIEW
Mitochondria
Vacuole
Cell wall
Cell membrane
Chloroplast
Nucleus
Rough ER
Ribosomes

25. 1.2 – C – Micrographs & Drawings

26. IB BIO – 1.2
Electron micrographs are images obtained using an electron microscope. These can be used to observe internal structures. 26
Skills
S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.
Key Terms

27. Eukaryote structures micrograph
IB BIO – 1.2
Eukaryote structures micrograph 27
Skills
S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.
Identify the following structures in the micrograph ?
Structures:
Mitochondria
Lysosome
Key Terms

28. Epithelium Cell Micrograph
IB BIO – 1.2
Epithelium Cell Micrograph 28
Skills
S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.
Identify the following structures in the micrograph
Structures:
rER
Nucleus
Mitochondria
Lysosome
Golgi Apparatus
Free Ribosomes
Key Terms

29. Eukaryotes structures micrograph
IB BIO – 1.2
Eukaryotes structures micrograph 29
Skills
S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.
Identify the following structures in the micrograph
Structures ER
Nucleus
Nuclear membrane
Key Terms

30. Eukaryote structures micrograph
IB BIO – 1.2
Eukaryote structures micrograph 30
Skills
S3: Interpret electron micrographs to identify organelles and deduce the function of specialized cells.
Identify the following structures in the micrograph
Structures:
Vacuole
Chloroplast
Cell Wall
Key Terms

31. E. coli structures micrograph
IB BIO – 1.2
E. coli structures micrograph 31
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Identify the following structures in the micrograph
Structures:
Flagella
Cilia
Cell Wall
Key Terms

32. E. coli structures micrograph
IB BIO – 1.2
E. coli structures micrograph 32
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Identify the following structures in the micrograph
Structures:
Nucleoid
Cytoplasm
Cell Wall
Key Terms

33. E. coli structures micrograph
IB BIO – 1.2
E. coli structures micrograph 33
Understandings
U1: Prokaryotes have a simple cell structure without compartmentalization.
Identify the following structures in the micrograph
Structures:
Cytoplasm
Plasma membrane
Cell Wall
Nucleoid
Key Terms

34. IB BIO – 1.2 Animal Cell Diagram34
Skills
S2: Drawing of the ultrastructure of eukaryotic cells based on electron micrographs.
Guidance
G2: Drawings of should show a membrane enclosing cytoplasm that contains ribosomes and membrane-bound organelles
Rough ER Cell Membrane Nucleus Ribosomes Golgi Apparatus Mitochondrion

35. IB BIO – 1.2 Plant Cell Diagram35
Skills
S2: Drawing of the ultrastructure of eukaryotic cells based on electron micrographs.
Guidance
G2: Drawings of should show a membrane enclosing cytoplasm that contains ribosomes and membrane-bound organelles
Rough ER Cell Membrane Nucleus Ribosomes Golgi Apparatus Mitochondrion Cell Wall Vacuole Chloroplast

36. IB BIO – 1.2 Prokaryote Diagram36
Skills
S1: Drawing of the structure of prokaryotic cells based on micrographs.
Guidance
G1: Drawings of prokaryotic cells should show the cell wall, pili and flagella, and membrane enclosing cytoplasm that contains ribosomes and a nucleoid with naked DNA.
Cell Wall Plasma Membrane Cilia Flagella 70S Ribosomes Nucleoid

37. REVIEW IB BIO – 1.2 Compare prokaryotes and eukaryotes.
Compare the structure of plant and animal cells.
Outline the functions of the following organelles: - Nucleus - Cell Membrane - Mitochondria - Chloroplast - Cell Wall - Vacuole - Flagella - Cilia - Vesicle - Rough ER - Golgi Apparatus - Nucleoid
Draw and annotate diagrams of: - Prokaryotic Cell - Animal Cell - Plant Cell 37
REVIEW