311C S12 L7OL - Introduction to Cells Cell Theory All...

Info iconThis preview shows pages 1–20. Sign up to view the full content.

View Full Document Right Arrow Icon
Introduction to Cells
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Cell Theory All living organisms are made up of cells The cell is the structural and functional unit of all living organisms All cells come from pre-existing cells
Background image of page 2
Common features of cells Plasma membrane Cytosol and cytoplasm Cytosol: semifluid aqueous solution Cytoplasm: Cytosol + suspended particles + organelles Everything outside of DNA region
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Common features of cells DNA Stores genetic information Organized into one or more chromosomes Ribosomes
Background image of page 4
Common features of cells Must obtain energy and raw materials (nutrients) Small!
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 6.2 10 m 1 m 0.1 m 1 cm 1 mm 100 μ m 10 μ m 1 μ m 100 nm 10 nm 1 nm 0.1 nm Atoms Small molecules Lipids Proteins Ribosomes Viruses Smallest bacteria Mitochondrion Most bacteria Nucleus Most plant and animal cells Human egg Frog egg Chicken egg Length of some nerve and muscle cells Human height Unaided eye Light microscopy Electron microscopy Super- resolution microscopy Cells are (usually) small
Background image of page 6
Cells are (usually) small The logistics of carrying out cellular metabolism sets limits on the size of cells Lower limit set by basic requirements for life Upper limit set by surface area-to-volume ratio
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Surface area increases while total volume remains constant Total surface area [sum of the surface areas (height × width) of all box sides × number of boxes] Total volume [height × width × length × number of boxes] Surface-to-volume (S-to-V) ratio [surface area ÷ volume] 1 5 6 150 750 1 125 125 1 1.2 6 6 Figure 6.7 Why Cells Are Small
Background image of page 8
Studying Cells
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Microscopy
Background image of page 10
Figure 6.4 TECHNIQUE Homogenization Tissue cells Homogenate Centrifugation Differential centrifugation Centrifuged at 1,000 g (1,000 times the force of gravity) for 10 min Supernatant poured into next tube 20,000 g 20 min 80,000 g 60 min Pellet rich in nuclei and cellular debris 150,000 g 3 hr Pellet rich in mitochondria (and chloro- plasts if cells are from a plant) Pellet rich in “microsomes” (pieces of plasma membranes and cells’ internal membranes) Pellet rich in ribosomes Cell Fractionation Separation and isolation of cellular contents Centrifuge Biochemical analysis
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Cellular Diversity: Two types of cells Prokaryotic cells Domain Bacteria Domain Archaea Eukaryotic cells Domain Eukarya
Background image of page 12
Prokaryote v. Eukaryote
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 14
Prokaryotic Cells Smaller Do not contain a nucleus Do not contain membrane-bound organelles
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Prokaryotic Cell
Background image of page 16
Prokaryotic Characteristics Cell shapes Cell surface structures Motility Internal organization Genomic organization
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Prokaryotic Cell Shapes 1 μ m 2 μ m 5 μ m (a) Spherical (cocci) (b) Rod-shaped (bacilli) (c) Spiral
Background image of page 18
Prokaryotic Cell Surface Structures Cell wall Maintains cell shape Provides physical protection Prevents bursting Peptidoglycan layer Cell wall Plasma membrane Protein Gram- positive bacteria 20 μ m Outer membrane Peptidoglycan layer Plasma membrane Cell wall Lipopolysaccharide Protein Gram- negative bacteria
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 20
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 80

311C S12 L7OL - Introduction to Cells Cell Theory All...

This preview shows document pages 1 - 20. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online