Cells: Prokaryote vs Eukaryote 1

Two Type Of Cells: Prokaryote “style” Eukaryote “style” 2

Prokaryote cells are smaller and simpler Commonly known as bacteria 10-100 microns in size Single-celled(unicellular) or Filamentous (strings of single cells) 3

Prokaryotic Eukaryotic Group of organisms that lack a cell nucleus (= karyon), or any other membrane-bound organelles. An organism whose cells contain complex structures enclosed within membranes and a nuclear membrane around DNA.

http://learn.genetics.utah.edu/content/begin/cells/scale/ Cell Size and Scale

BACTERIA - This is what you will see!!! VERY SMALL

Stronger Microscope!!!

Euglena

Paramecium

Amoeba

Onion Root

Frog blood & Sickle Cell Anemia

Prokaryote vs Eukaryote Two structural types of cells are recognized: Prokaryotic Archaea and bacteria Eukaryotic: plants, algae, fungi, protists, and animals (variety) Comparing prokaryotic and eukaryotic cells Prokaryote comes from the Greek words for prenucleus. Eukaryote comes from the Greek words for true nucleus.

Prokaryote Introduction Prokaryotes are much more diverse in both habitat eukaryotes. Nearly all prokaryotes are single-celled. Two major kingdoms: the Eubacteria (sometimes just called Bacteria) and the Archaea (or Archaebacteria). Very different genetically.

Prokaryotic Examples ONLY Bacteria And archae bacteria

Prokaryotes vs. Eukaryotes All living things are classified into two major groups. They are either Prokaryotes or Eukaryotes. Prokaryotes Eukaryotes *Have a defined nucleus *Membrane-bound organelles *May be single or multi- cellular * No definite nucleus * No membrane bound organelles *All are bacteria! *Unicellular

Simpler internal structure Prokaryotic vs. Eukaryotic Cells Prokaryotic cells No Nuclear membrane No Organized Organelles Cell Wall of peptidoglycan 1 circular chromosome Smaller ribosomes Eukaryotic Cells Nucleus Organelles If cell wall, Cellulose or chitin Linear chromosomes Ribosomes bigger

Prokaryotic Cells Shapes of Bacterial Cells cocci bacilli spiral

E. coli bacteria on the head of a steel pin. These are prokaryote E. coli bacteria on the head of a steel pin. 19

Prokaryote cells are simply built (example: E. coli) capsule: slimy outer coating cell wall: tougher middle layer of peptidoglycan cell membrane: delicate inner skin 20

Prokaryote cells are simply built (example: E. coli) cytoplasm: inner liquid filling DNA in one big loop pilli: for sticking to things flagella: for swimming ribosomes: for building proteins 21

Prokaryote lifestyle unicellular: all alone colony: forms a film filamentous: forms a chain of cells 22

Prokaryote Feeding Photosynthetic: energy from sunlight Disease-causing heterotrophs: feed on living things Decomposers: feed on dead things 23

Motility Almost all Spiral bacteria are motile About 1/2 of Bacilli are motile Almost all Cocci are non-motile

How Do Antibiotic Work on Bacteria without Killing Host Cell? 1. Attack Bacteria cell wall 2. Attack bacteria ribosomes Both of these structures are different in prokaryotics so drugs can specifically target them!!!

Bacterial cell wall - chemically unlike any other structure in Animal cells Target for drugs that can attack and kill bacteria without harming the host cell MANY ANTIBIOTICS are specifically directed at Cell Wall Synthesis Penicillin works by damaging the pentaglycine crossbridges of the peptidogylcan layer Works best against Gram (+) bacteria

Selective Toxicity Some antibiotics are aimed at the ribosomes of bacterial cells Streptomycin, Neomycin, Erythromycin and Tetracycline work by inhibiting protein synthesis by disrupting the ribosome

Eukaryotic Cells A eukaryote ( or ) is an organism whose cells contain complex structures enclosed within membranes including DNA.

Eukaryotes are bigger and more complicated Have organelles Have chromosomes can be multicellular include animal, plant, protists and fungi cells 29

Organelles are membrane-bound cell parts Mini “organs” that have unique structures and functions Located in cytoplasm 30

Cell Structures Cell membrane *semipermeable - allowing some items in and blocking others *delicate double layer of phosolipodslipid and protein skin around cytoplasm found in all cells 31

Nucleus a membrane-bound sac evolved to store the cell’s chromosomes and nucleolus Surrounded by membrane that has pores: holes Both plants and animals 32

Nucleolus inside nucleus location of ribosome factory made or RNA Both plants and animals 33

Mitochondrion converts glucose into ATP for energy Inner membrane folded into cristae the more energy the cell needs, the more mitochondria it has Both in plants and animals 34

Ribosomes Site of protein synthesis from amino acids may be free-floating, or may be attached to ER made of RNA Both plants and animals 35

Endoplasmic reticulum (smooth) may be smooth: builds lipids and carbohydrates. No ribosomes!! Controls Ca levels in muscles Both plants and animals 36

Rough ER Rough because covered in ribsomes. Transports material through the cell and produces proteins in sacs called cistern. Both plants and animals

Golgi Complex Flattened sacs that modifies proteins and packages them into vesicles for export. Both plants and animals 38

Lysosomes sacs filled with digestive enzymes digest worn out cell parts digest food absorbed by cell Both plants and animals 39

Centrioles Dense center of centromere pair of bundled tubes organize cell division Both plants and animals 40

Cytoskeleton made of microtubules found throughout cytoplasm gives shape to cell & moves organelles around inside. Both plants and animals 41

Structures found in plant cells Cell wall very strong made of cellulose protects cell from rupturing glued to other cells next door 42

Vacuole huge water-filled sac keeps cell pressurized stores starch 43

Chloroplasts filled with chlorophyll turn solar energy into food energy 44

How are plant and animal cells different? 45

Structure Animal cells Plant cells cell membrane Yes yes nucleus nucleolus ribosomes ER Golgi centrioles no cell wall mitochondria cholorplasts One big vacuole cytoskeleton 46

Eukaryote cells can be multicellular The whole cell can be specialized for one job cells can work together as tissues Tissues can work together as organs 47

Advantages of each kind of cell architecture Prokaryotes Eukaryotes simple and easy to grow can specialize fast reproduction multicellularity all the same can build large bodies 48

Examples of specialized euk. cells liver cell: specialized to detoxify blood and store glucose as glycogen. 49

Examples of specialized euk. cells liver cell: specialized to detoxify blood and store glucose as glycogen. 50

sperm cell: specialized to deliver DNA to egg cell 51

Mesophyll cell specialized to capture as much light as possible inside a leaf 52

How do animal cells move? Some can crawl with pseudopods Some can swim with a flagellum Some can swim very fast with cilia 53

Pseudopods means “fake feet” extensions of cell membrane example: ameoba 54

Flagellum/flagella large whiplike tail pushes or pulls cell through water can be single, or a pair 55

Flagellum/flagella large whiplike tail pushes or pulls cell through water can be single, or a pair 56

Cilia fine, hairlike extensions attached to cell membrane beat in unison 57