Unit 1 - Introduction to the Cell Flashcards
(31 cards)
Transmission Emission Microscopy
looks at thin sections of tissues - the ‘guts’ of the cell
Fluorescence Microscopy
illumination and electronic image processing, sees cell components in finer detail
Yeast (Saccharomyces cerevisiae)
cell cycle/mitosis
worm - C. elegans
first animal genome to be sequenced
E.coli
DNA replication
Evidence of endosymbiont theory
M & C …
- similar size to bacteria
- double membranes
- own ribosomes
- own genomes
- genetically-similar to ‘parent’ bacteria as apposed to eukaryotic cells
Endosymbiont Theory
- early eukaryotes originated as predators
- mitochondria and chloroplasts evolved from smaller prokaryotes that were engulfed by larger cells
Mitochondria
generates energy to power cell
Golgi
collection, packaging and distribution
Rough ER
synthesis of proteins for export, insertion into membranes, lysosomes
Nucleus
stores chromosomes, DNA
Animals
- Multicellular
- Heterotrophs
- No cell walls
Plants
- Autotrophs - self-feeding
- cell walls
- multicellular
Fungi
- single celled or multi cellular
- cell walls
- heterotrophs - dependent on external source of organic compounds
Protists
- single celled
- most diverse group
- much larger compared to bacteria
Prokaryotic Cell Shapes
- Rod-like
- Spherical
- Corkscrew
Generic Prokaryotic Cell
- No membrane-bound nucleus
- DNA is a single strand, circular and free-floating
- Most have a cell wall in addition to the plasma membrane
- Ribosomes, plasmids, cytoplasm, chromosomes, flagellum (occasionally)
archeabacteria
have cell walls
(eu)bacteria
have cell walls (exception: mycoplasma)
Functions of All Cells
- Acquire and use energy
- Carry out a variety of chemical reactions (cellular metabolism)
- Engage in mechanical activities (transport, assembly/disassembly, movement)
- Respond to signals
The Cell Theory
- All living organisms are composed of cells
- The cell is the basic unit of structure for all organisms
- All cells arise from pre-existing cells
Theodore Schwann
1839, similar aspects observed in animal cells
Matthias Schleiden
Schleiden
1838, embryonic plants arose from single cell, all plant tissue composed of cells
Robert Brown
1833, noticed every plant cell had a ‘kernel’ - later names nucleus