Transcript Identifying Plant cELLS - Educational Excellence

Discovering the Plant Cell
Advanced Biotechnology c 5 (C)
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
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.
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
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
Plant Cell vs Animal Cell
Animal Cell
• Various sizes and shapes
• Smaller than plant cells
• Organelles typically not
found in plant cells:
– Centrioles
– Lysosomes
– Cilia/flagella
Plant Cell
• Consistent shape and size
– Typically “cube-ish”
• Organelles typically not
found in animal cells:
– Cell wall
– Large vacuole
– Plastids
• Chloroplasts
Organelles
• Cell (Plasma)
Membrane
• Cell Wall
• Chloroplast
• Cytoplasm
• Cytoskeleton
• Endoplasmic
Reticulum (ER)
• Golgi Complex
• Microtubules
• Mitochondria
• Nucleus
• Nucleolus
• Nucleopore
•
•
•
•
Peroxisomes
Plasmodesmata
Ribosomes
Vacuole
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.
Cell Wall
Plant Cell
• Mostly
composed of
cellulose
Animal Cell
• No cell wall
Bacteria Cell
• 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.
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
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.
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.
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
Microtubules
• Component of the cytoskeleton
• Helps maintain structure of a cell
• Involved in cellular processes and
intracelluar transport
http://images.nigms.nih.gov/index.cfm?event=view
Detail&imageID=3611
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).
Nucleus
• Contains most of the cell’s
genetic material
Blausen.com staff. "Blausen gallery 2014". Wikiversity Journal of
Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762.
Cell is
undergoing
mitosis
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
Nucleolus
• Inside the nucleus is the nucleolus
• Ribosomes are made inside the nucleolus
Peroxisome
• Produces enzymes for the breakdown of fatty
acids
• Assist in photorespiration of leaves and
germination of seeds.
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
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
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
Vacuoles
Identification Game
• http://www.sheppardsoftware.com/health/an
atomy/cell/plant_cell_game.htm