prokaryotes and eukaryotes Flashcards
what is a prokaryote?
A microscopic single-celled organism which has neither a distinct nucleas with a membrane nor other specialised organelles
Give two examples of prokaryotes
1) Bacteria
(Bacillus anthracis [causes Anthrax], Escherichia coli [food posoning], Yersinia pestis [causes plague]
2) Archaea
(sulfolobus spp [found in hotsprings], methanosarcina rumen [found in the rumen, produces methane gas and thrives in areas with little or no oxygen], staphylothermus marinus [found in deep-sea hypothermal vents, can survive high temperatures]
What is a Eukaryote?
A cell which contains a nucleas and other membrane-bound organelles.
(Plants, animals, fungi and protists are all eukaryotes)
Describe the cell walls of eukarytotes and prokaryotes
Eukaryotes
simple- cellulose or chitin
Prokaryotes
chemically complex- typically peptidogylcan
Describe the chromosomes of prokaryotes and eukaryotes
prokaryotes
single, curcular chromosomes without histones
eukaryotes
multiple, linear chromosomes with histones
Describe how cell division occurs in prokaryotes and eukaryotes
prokaryotes
binary fission
eukaryotes
mitosis
Name three kinds of animal cells
Stem cells
Somatic cells
Germ-line cells
What are stem cells?
Eukaryotic cells
Able to differentiate into specialised cells in the body
Can also divide by mitosis to provide more stem cells
What are somatic cells?
Eukaryotic cells
With specialised functions dependent on location, anatomy and physiology
Often referred to as ‘body cells’ and reproduce via mitosis
What are germ-line cells
Eukaryotic cells
Sex cells: sperm and ova
Reproduce via meiosis and their sole purpose is for fusing with each other to create offspring
Name two pathogenic eukaryotes
Fungi
(most common thrush infections in humans)
Protozoa
(malaria: [lasmodium falciparum)
