The CellCell Types

&Cell Parts

Cell Types

P lan t A n im a l F u n g i P ro tis ta

E u karyo teH ave N u c leu s

B ac te riaK in d g om M on era

P rokaryo teN o N u c leu s

C e ll Typ es

Prokaryotic Cells orProkaryotes

The Bacteria

Capsule

• A protective covering

• Made up of polysaccharides

• Keep the bacterium from drying out & to protect it

• The capsule is a major virulence factor in the major disease-causing bacteria,

• E.g. Escherichia coli and Streptococcus pneumoniae.

Cell Wall• Gives the cell its shape

• Surrounds the plasma membrane, protecting it from the environment.

• Helps to anchor appendages (pili and flagella)

• Responsible for keeping the cell from bursting when there are large differences in osmotic pressure between the cytoplasm and the environment.

Nucleoid• A region of cytoplasm where the

chromosomal DNA is located.

• It is not a membrane bound nucleus

• Most bacteria have a single, circular chromosome

• Small circular DNA strands, called plasmids, are also found in the cytoplasm.

Pili

• Small hairlike projections emerging from the outside cell surface.

• Assist the bacteria in attaching to other cells and surfaces, such as teeth, intestines, and rocks.

• Without pili, bacteria lose their ability to infect

because they're unable to attach to host tissue.

Prokaryotic Ribosomes

• Site of protein synthesis

• Bacterial ribosomes are never bound to other organelles

Bacterial Shapes

Bacterial Arrangements

Eukaryotic Cells Or Eukaryotes

Nucleus & Membrane Bound

Organelles

Animal Cell

Cell Membrane

VacuoleCytoplasm

Nucleus

Nucleolus

RibosomeRough Endoplasmic Reticulum

Nuclear Membrane

LysosomeGolgi Apparatus

Mitochondria

SmoothEndoplasmic Reticulum

Centriole

http://micro.magnet.fsu.edu/cells/animals/animalmodel.html

Plant Cell

Cell Membrane

Vacuole

Cytoplasm

NucleusNucleolus

Ribosome

Rough Endoplasmic Reticulum

Nuclear MembraneGolgi Apparatus

Mitochondria

SmoothEndoplasmic Reticulum Chloroplast

Cell Wall

http://micro.magnet.fsu.edu/cells/plants/plantmodel.html

Cell Membrane• Controls what enters and leaves cell

• Protects and supports the cell

• Made of a Phospholipid Bi-layer

• Proteins – act as channels, carriers, or pumps to pass molecules into or out of the cell

• Cholesterol molecules prevent phospholipids from sticking to each other

• Fluid Mosaic

Phospholipid Bilayer

Cell Membrane

Cell Membrane

• Carbohydrate chains

• Act like chemical ID cards – allows cells to recognize each other.

Cell Wall• Plants, algae, some bacteria • Helps support and protect cell• 2 or more layers thick

– Outer layer is where cells meet – gluey substance – pectin

– Primary cell wall is next – made of cellulose

Nucleus• large dark structure• Not all cells have a nucleus

– Eukaryotes– Prokaryotes

• Information center and holds DNA (genetic code)

• Chromosomes – DNA and Proteins – Genetic code

Nucleolus

• Inside Nucleus• Made of RNA• Makes Ribosomes

– Ribosomes are the site of protein synthesis

Cytoplasm• Jelly like substance• Holds organelles• Most chemical reactions happen

here

Cytoplasm• Made up of

* Proteins including enzymes * Vitamins * Ions * Nucleic acids and their precursors * Amino acids and their precursors * Sugars, carbohydrates and their derivatives * Fatty acids and their derivatives

• These are all part of continuous chemical reactions.

Mitochondria• Powerhouse of the cell• Break down sugars for energy

– Convert ADP to ATP

• 2 Membranes– Outer surrounds mitochondria– Inner increases surface area – more

efficient

Mitochondrion

Chloroplast• Only in plant cells• Have Chlorophyll• Convert Sun energy into chemical

energy

Chloroplast

Ribosome• Composed of RNA and protein • some attached to membranes, some

free • smallest organelles

·  25 nanometers (1 billionth of a meter)

Endoplasmic Reticulum• Network of channels – ER

• Transports materials through the inside of the cell

• Rough ER – Has Ribosomes covering it

• Smooth ER – NO RIBOSOMES ON IT (Detoxifies)

• Synthesized proteins are moved to Golgi Apparatus for modification

Golgi Apparatusor Golgi body

• Looks like flattened stack of pancakes • Modifies, collects, packages, and

distributes proteins

Lysosomes The Cleanup Crew

• Lysosomes help digest particles – contain enzymes and chemicals necessary for digestion

• Break down organelles that have outlived their usefulness

• Formed by Golgi Apparatus

• Only in Animal Cells

Cellular Junctions