Cell Structure and Organization

5.1 Cell theory and size

What is a cell? Smallest unit of living matter First discovered in 1700s with

microscope Cell theory

All organisms are made of cells Cells are the smallest unit of living

matter Cells come from pre-existing cells Cells are self-reproducing

Why are cells so small? Surface area Volume Ratio determines

ability of substances to enter cell Need high SA to vol.

ratio

Cell Structure and Organization

5.2 Prokaryotic cells

What is a prokaryotic cell again? Pro = _______ Karyo = ________ Eu = ________ Prokaryotes include

Archeae Bacteria

What is inside a bacterial cell—1? No true organelles Cell envelope

Cell wall Peptidoglycan

Plasma membrane Mesosomes

Where most metabolic activities occur Glycocalyx

Capsule

What is inside a bacterial cell—2? Cytoplasm

Nucleoid region Circular chromosome

anchored to _____ Plasmids

Ribosomes Inclusion bodies Thylakoids

(cyanobacteria) Appendages

Fimbriae Flagella Sex pili

What’s different inside an Archeae cell? More cell shape

diversity No peptidoglycan

in cell wall Other similar

molecules Most likely

ancestor for eukaryotes

Cell Structure and Organization

5.3 Eukaryotic cells

What distinguishes eukaryotes from prokaryotes? Eukaryotes

Nucleus True organelles

Membrane bound Compartmentalization

Keeps incompatible rxns separate Increases efficiency of rxns

Derived from prokaryotic ancestor Endosymbiotic hypothesis

What organelles are found in eukaryotes? Nucleus Mitochondria Endomembrane

system Lysosomes Peroxisomes

vesicles and vacuoles

Choloroplast (only in plant cells)

What other structures are found in eukaryotes? Ribosome Cytoskeleton Centriole Cilia and

flagella

What is the nucleus composed of? Chromatin Chromosomes Nucleoplasm Nuclear envelope Nucleotides Nuclear pore

What is the mitochondria composed of? Inner and outer

membrane Cristae Matrix

What are lysosome, peroxisomes ,veiscles and vacuoles? Lysosomses

recycling system Peroxisomes

Specialized Peroxides

Vesicles Membraneous sacs

Vacuoles Larger than vesicles

What is the endomembrane system?

Parts Nuclear

envelope ER Golgi vesicles

Secretory pathway hypothesis Describes

production, packaging and export of proteins

What are ribosomes? Protein synthesis Two sub-units Differ in ‘s’ value

collect, package, and distribute molecules synthesized at one location in the cell and utilized at another location

What kind of Cytoskeleton are present in the cell?

actin filaments intermediate filaments microtubules Functions:

cell shape cell movement transport of materials anchoring organelles

What are cilia and flagella? Cilia

Hairlike many

Flagella Whiplike One or two 9 + 2 pattern Functions: movement