1. Tour Of The Cell
Chapter 6

2. Microscopy
What is the difference between magnification and resolving power?
Magnification is how much larger the object can now appear
Resolving power is the ability to distinguish between two points It is limited by the wavelength of visible light

3. The different microscopes
Light microscope - resolving power is limited by the wavelengths of light
Specimen should be stained, but can be alive
compound microscope
stereomicroscope
Electron microscope - resolving power is greater since wavelengths of electrons are smaller than those of light
SEM - 3D image
TEM - flat image
electron microscopes cannot use live specimens

5. How did scientists first discover the different cell parts?

6. As organisms get larger, why do they become multicellular?

7. It’s all about the surface area to volume ratio!

8. Prokaryotic vs. Eukaryotic Cells
Prokaryotic cells
Bacteria, Archaea
genetic material not in a nucleus
no membrane bound organelles
Eukaryotic cells
Protists, Plants, Fungi and Animals
true nucleus with genetic material
has membrane bound organelles

9. The Prokaryotic Cell

10. The Plasma Membrane

11. General Eukaryotic Cells

13. Two Areas of the Eukaryotic Cell
What is the space between the cell membrane and the nucleus called?
The cytoplasm. This includes the organelles and the cytosol
The cytosol is the fluid medium found in the cytoplasm

14. The nucleus

15. Nuclear Components
Envelope = double layered membrane that has pores for molecular transport
Chromatin = DNA + protein complex of threadlike fibers that make up the eukaryotic chromosome
Chromosome = Chromatin fibers condense into visible chromosomes during cell division

16. Ribosomes Prokaryotic ribosomes differ from eukaryotic ribosomes
Function = Site of protein synthesis

17. The Endomembrane system
Related through direct continuity or by transfer on membrane segments through vesicles
Structure of membranes is not identical
Includes:
Nuclear envelope --> Endoplasmic reticulum --> Golgi apparatus --> lysosomes --> vacuoles -->plasma membrane

20. Transport vesicle from ER
New vesicle forming
Transport vesicle from Golgi

21. Functions of Golgi apparatus
Modifies stores and routes products of ER
Alters membrane phospholipids
Targets products for parts of the cell

23. Vacuoles Larger than vesicles food vacuoles = formed by phagocytosis
contractile vacuole = found in fresh water protozoans, keeps water balance
central vacuole = found in most plant cells stores organic compounds, has enzymes to break macromolecules, has poisonous and unpalatable compounds, etc.

25. Mitochondria and Chloroplasts
not part of endomembrane system
their membrane proteins are made by free ribosomes and their own ribosomes
both have small amount of DNA
grow and reproduce on their own within the cell
involved in energy transformation

27. Plastids amyloplasts - store starch, in roots and tubers
chromoplasts - non-chlorophyll pigments responsible for non-green colors
chloroplasts - chlorophyll containing plastids

29. Peroxisome
Contains enzymes that transfer hydrogen from substrates to oxygen producing hydrogen peroxide
Some use oxygen to fuel the breakdown of fatty acids to smaller molecules that can be used in the mitochondrion
In liver they detoxify alcohol and other poisons by transferring hydrogen from poison to oxygen
Hydrogen peroxide is toxic. What enzyme can be used to break this down?

30. Cytoskeleton Provides structural support
Functions in motility and motion

31. Microtubules cellular support
provides tracks for movement within the cell: e.g. transport vesicles
composes cilia and flagella, locomotive appendages of certain cells
separation of chromosomes during cell division (spindle fiber)
composes centrioles in animal cells

33. Microfilaments smaller than microtublues
participates in muscle contraction
support
localized cell contractions

35. The Cell Surface cell walls in plant cells
membrane linked channel - plasmodesmata that connects cytoplasm between cells

37. Animal Cell Surfaces
glycocalyx - strengthens cell surface, helps glue animal cells together
tight junctions - holds cells together to block transport
desmosomes - rivets cells together into strong sheets but permits transport
gap junctions - analogous to plasmodesmata in plant cells

40. Let’s Review Name the cell structure and its function
Be able to tell if this structure is found in prokaryote, eukaryote, plant and/or animal cells