I' Microscopy

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I. Microscopy

• magnification

Ocular x Objective

• resolving power

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Electron Microscopes
Better resolving power than light microscopes
TEM ? aims an electron beam at a thin stained
section
Used to study internal cell structure
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SEM ? beam scans the surface of a specimen coated
with a thin layer of gold

• Visualized entire image

• Creates a 3-D image

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BUT, EMs can only view dead cells
PHASE CONTRAST ? allow unstained, living tissues
to be observed
CELL FRACTIONATION ? using a centrifuge to
separate cell components based on
DENSITY
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PROKARYOTIC vs. EUKARYOTIC

• found in Kingdoms Protista, Fungi, Plantae,
  Animalia

• found only in Kingdom Monera

• no true nucleus lacks nuclear envelope

• true nucleus bounded by nuclear envelope

• genetic material in nucleoid region

• genetic material within the nucleus

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PROKARYOTIC vs. EUKARYOTIC

• contains cytoplasm w/ cytosol and membrane-bound
  organelles

• no membrane-bound organelles

• have a plasma membrane and usually a cell wall

• usually smaller than eukaryotes

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PROKARYOTIC vs. EUKARYOTIC
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CELL SIZE is limited by

• metabolic requirements

• surface area to volume ratio

II. PARTS of the CELL
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• nucleus

histones
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• cytoplasm

• cytosol

• nucleolus

• ribosomes

• endoplasmic reticulum

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• Golgi apparatus

• lysosomes

• intracellular digestion

• apoptosis

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• vacuoles

• peroxisomes

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• mitochondria

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• Cytoskeleton

• microtubules

• intermediate filaments

• microfilaments

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• cell walls

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• glycocalyx

• Intercellular Junctions

• tight junctions

• desmosomes

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• gap junctions

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IV. MEMBRANES

• Singer-Nicolson Fluid Mosaic Model

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• Selective Permeability

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• Water Potential

• hypoosmotic environments

• isotonic environments

• hyperosmotic environments

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• Diffusion and Osmosis

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• Facilitated Diffusion

• Active Transport

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• Forms of Active Transport

• ATP Pump

• Symport

• Antiport

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• Receptor-mediated endocytosis