Lecture six Flashcards
Tour of the cell
Compare and contrast the basic structural components of bacterial and eukaryotic cells
Bacterial cells - Sex pilus, flagella, ribosome, nucleoid, chromosomes, cell wall, capsule, fimbriae
Eukaryotic cells - membrane bound organelles (mitochondria), inner and outer membrane (matrix), nucleus, cytoplasma, cytosol, complex compartmentalisation, cystoskeleton
Describe essential functions carried out by major organelles in the eukaryotic cell
Animal cell:
Cytoskeleton (reinforces cell shape made of proteins)
Mitochondria (cellular respiration occurs and ATP is generated)
Lysosome (digestive organelle)
Peroxisome (produces hydrogen as a by-product then converts it to water)
Golgi apparatus (mod, sorting and secretion of cell products)
Ribosomes (bound to rough ER/nuclear envelope. Make proteins)
ER (active in membrane synthesis and metabolic processes)
Smooth ER (synthesis of lipids, storage of Calcium ions, detoxification of alcohol)
Rough ER (Proteins intended for special destinations, such as secretion out of the cell, are
threaded into the RER as they are made, and then chemically altered, usually by
glycosylation)
Plant cell:
Chloroplast (converts energy of sunlight to chemical energy stored in sugar molecules)
Central vacuole (storage and breakdown of waste products)
What are three components of the nucleus
Nuclear envelope - double membrane enclosing the nucleus
Nucleolus - involved in production of ribosomes
Chromatin - material consisting of DNA and proteins. Condenses chromosomes
Describe the endosymbiont theory of eukaryotic cell evolution and explain the major lines in evidence for thus?
Evolutionary theory which explains the origin of eukaryotes from ancestral prokaryotes. Proposes that (Mitochondria and Chloroplasts), evolved from free-living prokaryotes that were engulfed and subsequently became obligate endosymbionants.
List evidence to support the endosymbiont theory
− Chloroplasts and mitochondria have their own circular DNA (like prokaryotes) and
ribosomes.
− The size of these organelles is the same as many prokaryotes (chloroplasts are larger
than mitochondria, but prokaryotes vary considerably in size).
− They have multiple membranes.
− Chloroplasts and ribosomes reproduce (by binary fission, as do prokaryotes)
