1. Discovering the Plant Cell
Advanced Biotechnology c 5 (C)

2. Objectives The student will be able to:
Identify the parts of a plant cell
Describe the functions of each organelle
Compare plant cells to other cells

3. Intro to Plant Cells Plants cells have some unique structures
In particular, chloroplasts allow the plant to capture energy from the Sun
Eukaryotic cells
Means membrane-bound nucleus
Some organelles are similar between other types of cells.

4. Types of Specialized Plant Cells
Parenchyma Cells
Synthesize and store organic products, “filler” tissue; e.g., the soft part of the plant.
Collenchyma Cells
Extra structural support, esp. in areas of new growth
Sclerenchyma Cells
Provide main structural support

5. Plant Cell Characteristics
Plant cells generally larger than animal
Plant cells more consistent in size and shape
Unique structures:
Cell wall
Large vacuole
Plastids
chloroplasts

6. Plant Cell vs Animal Cell
Various sizes and shapes
Smaller than plant cells
Organelles typically not found in plant cells:
Centrioles
Lysosomes
Cilia/flagella
Consistent shape and size
Typically “cube-ish”
Organelles typically not found in animal cells:
Cell wall
Large vacuole
Plastids
Chloroplasts

7. Organelles Cell (Plasma) Membrane Mitochondria Nucleus Cell Wall
Nucleolus
Chloroplast
Nucleopore
Peroxisomes
Cytoplasm
Plasmodesmata
Cytoskeleton
Ribosomes
Endoplasmic Reticulum (ER)
Vacuole
Golgi Complex
Microtubules

9. Plasma Membrane Plasma Membrane:
Similar to other cell type plasma membranes
Phospholipid bilayer acts as a permeability barrier.
Location for transport of molecules into the cell.

10. Cell Wall Plant Cell Animal Cell Bacteria Cell
Mostly composed of cellulose
No cell wall
Prokaryotic cells made up of murein aka peptidoglycan.
The cell wall is a rigid layer on the outside of the plasma membrane. The cell wall offers structural support, filtration, and protection.

11. Chloroplasts Only found in plants Contain chlorophyll
Green pigment that makes plants green
Main function is photosynthesis
Chloroplasts contain their own DNA
Chloroplasts can host transgenes – better isolated than nuclear transformation

13. Cytoskeleton Supports cell shape and function.
Composed of proteins which can assemble or disassemble as the needs of the cell change.
Found in cells of all domains of life.

14. Endoplasmic Reticulum
Two types:
Rough (RER)
System of sacks found in cell’s cytoplasm
Rough is covered with ribosomes that give it a rough appearance.
Functions as transport through the cell, produces proteins
Transport vesicles take proteins from RER to Golgi apparatus
Smooth
System of tubes located in cytoplasm.
Function as transport through the cell.
Contains enzymes to assist in digestion of lipids proteins
Smooth ER buds off of rough ER.

15. Golgi Complex Also known as Golgi body or apparatus.
Flattened and layered organelle. Resembles a stack of pancakes.
Receives the vesicles from RER and converts proteins and lipids to various useable products
Transports out vesicles

16. Microtubules Component of the cytoskeleton
Helps maintain structure of a cell
Involved in cellular processes and intracelluar transport

17. Mitochondria Found in most eukaryotic cells.
The “powerhouse of the cell”.
Generate most of the cell’s adenosine triphosphate (ATP)  chemical energy
Maintains control over the cell cycle/growth.
Mitochondria has it’s own DNA (mtDNA).

18. Cell is undergoing mitosis
Nucleus
Cell is undergoing mitosis
Contains most of the cell’s genetic material
Blausen.com staff. "Blausen gallery 2014". Wikiversity Journal of Medicine. DOI: /wjm/  ISSN 

19. Nucleus continued Contains chromosomes which house the DNA
Nuclear pores around the nuclear membrane allow molecules to move across the membrane.
Movement is needed for gene expression and chromosome maintenance

20. Nucleolus Inside the nucleus is the nucleolus
Ribosomes are made inside the nucleolus

21. Peroxisome Produces enzymes for the breakdown of fatty acids
Assist in photorespiration of leaves and germination of seeds.

22. Plasmodesmata
Microscopic channels traversing cell walls of plant cells
Transport proteins, mRNA, viral genomes from cell to cell
Viral movement example: tobacco mosaic virus MP-30

23. Ribosomes
Ribosomes are technically NOT an organelle as they are non-membrane bound.
Free-floating and attached to rough endoplasmic reticulum.
Site of protein synthesis.
RNA translated into protein

24. Vacuole Present in all plant and fungal cells
Some protist, animal, and bacterial cells
Enclosed compartments filled with water
Functions:
Containing waste products
Containing water
Maintaining internal hydrostatic pressure
Support structures such as leaves and flowers

25. Vacuoles

26. Identification Game