1. Cell Biology & Cell Organelles

2. Anton von Leeuwenhoek (1674)
Get Hooke-d on Cells!
Scientist
Discovery
Robert Hook (1665)
Described the empty spaces between cork as “cells”
Actually viewed the cell walls of dead cells
Anton von Leeuwenhoek (1674)
First observed a living cell (identified bacteria)
John Dalton (1808)
Atomic Theory
All matter is made of atoms
Louis Pasteur (1864)
Living organisms can only arise from other living organisms

3. Cell Theory Cells are the basic unit of life
All organisms are made of one or more cells
All cells must come from pre-existing cells
The activity of an entire organism depends on the total activity of its independent cells

4. Prokaryote Cells Pro: before; karyote: nucleus First cells to evolve
Do not contain a membrane-bound nucleus
Do not contain organelles smaller than a ribosome
Bacteria
DNA is single, circular strand
Cell wall used as a target for antibiotics
Pseudomonas Bacteria

5. Eukaryote Cells Eu: good/true; karyote: nucleus
More complex internal structure and includes a nucleus
Include membrane-bound organelles
Early prokaryotes were engulfed by other prokaryotes and remained within
This formed a symbiotic relationship
Created a eukaryotic cell
Plant, animal, fungi, protists

6. Nucleus Structure Function
Large oval structure in the centre of the cell
Bound by the nuclear membrane
Contains the chromosomes and the nucleolus
Function
Control centre of the cell
Regulates all activities of the cell

7. Nucleolus Structure Function Small, dark area within the nucleus
Where ribosomes are made

8. Nuclear Membrane Structure Function
Encloses the nucleus of the eukaryotic cell
Function
Prevents the contents of the nucleus from being spread in the cytoplasm

9. Nuclear Pores Structure Function Openings in the nuclear membrane
Allows contact between the nucleus and cytoplasm
Allows ribosomes produced by nucleus (nucleolus) to move into the cytoplasm

10. Chromosomes Structure Function
Threadlike structures found in the nucleus
Function
Made of DNA which carries genetic information
DNA coils and become visible during cell division
Directs cell activities
Hereditary material
Chromosome = DNA + protein

11. Cell Membrane Structure Function
Bilayer of phospholipids with proteins embedded within it
Fluid and flexible
Phospholipid
Hydrophilic head
Hydrophobic tail
Function
Regulates the passage of materials in and out of the cell

12. Cytoplasm Structure Function
Everything between the cell and nuclear membrane
Consists of cytosol (mostly water) and organelles
Function
Organelles carry out functions within the cell

13. Cytoskeleton Structure Function Microtubules & Microfilaments
Tiny, tube-like fibres found in cytoplasm, cilia, flagella
Function
Maintains the shape of the cell
Microtubules
Transport materials throughout cytoplasm
Microfilaments
Help provide shape and movement for cells

14. Organelles - Mitochondria
Structure
Rod-shaped
Smooth outer membrane with a greatly folded inner membrane (cristae) which increases the surface area
Function
Powerhouse of the cell
Where food molecules are broken down and their energy used to make special energy-rich molecules

15. Organelles - Ribosome Structure Function
Small, grain-like body made primarily of RNA
Lack a membrane
May be attached to endoplasmic reticulum or floating freely in cytoplasm
Made in the nucleolus
Function
Site of protein synthesis

16. Organelles – Endoplasmic Reticulum
Structure
System of clear, tubular passageways which spreads through cytoplasm
Smooth: No ribosomes attached
Rough: Ribosomes attached
Function
Smooth: Transports proteins produced by ribosomes throughout the cell
Rough: Transports fats and proteins (synthesized on SER) throughout the cell

17. Organelles – Endoplasmic Reticulum
Smooth
Rough

18. Organelles – Golgi Apparatus
Structure
Membranous sacs piled on top of each other
Function
Modifies, collects, packages, and distributes proteins made in one location and used in another
Proteins released by exocytosis

19. Organelles – Lysosome Structure Function Small, round sac in cytoplasm
Contains digestive enzymes
Formed by the golgi apparatus
Function
Suicide sacs
Breaks down food, old cell parts, and dead or injured cells

20. Organelles – Vacuoles Structure Function Sac-like structures
Larger in plants than animals
Function
Store water, salts, proteins, and carbohydrates.
Allow plants to support leaves and flowers

21. Organelles – Plastids Structure Function Found only in plants
Similar structure to the vacuole
Function
Chloroplast: use sunlight for energy
Leukoplast: store starch granules
Chromoplast: Store pigment molecules (orange, yellow)

22. Organelles – Chloroplast
Structure
Large, green structure in the cytoplasm
Contains chlorophyll
Thylakoid: outer membrane
Stroma: inner membrane
Grana: stacks of chlorophyll
Function
Captures energy in sunlight and uses it to produce food

23. Organelles – Centrioles
Structure
Two bundles of fibres at right angles
Found in animal cells only
Present during mitosis (cell division)
Function
Migrate to poles during mitosis
Microtubules form between centrioles to pull chromosomes apart

24. Plant vs. Animal Cells Plant cells Animal Cells
Cell wall made of cellulose for support
Chloroplasts which convert energy through photosynthesis
Large vacuoles
No lysosomes
Animal Cells
Centrioles aid in cell division
Small vacuoles

25. Animal Cells

26. Plant Cell