Basics of Cells Flashcards
What is the primary difference between prokaryotes and eukaryotes?
There is no membrane around the cell’s genetic information in prokaryotes.
Give some other key differences between prokaryotes and eukaryotes in terms of the organelles present
Prokaryotes have one DNA molecule, eukaryotes more than one. Eukaryotes have mitochondria, Golgia apparatus, endoplasmic reticulum, nuclear membrane and low heat resistance. Prokaryotes do not have these components but they are heat resistant due to presence of cell wall.
What genetic material do viruses contain?
Either deoxyribonucleic acids or ribonucleic acids.
What is the genetic material covered by in a virus?
A protein coat called a capsid
What are the stages of viral injection?
Bacteriophages (bacterial-infecting viruses) attach to the cell wall of a host cell. Inject viral nuclear material into the host cell. The bacteriophage nucleic acids reproduce inside the host cells to produce more phages. Host cells lyse or break apart and the phage particles are released to infect new host cells.
How can viruses be useful in genetic engineering?
Replace viral genetic material with desired genes to be inserted into patient. Viral capsid protects inserted gene in human host until reaches targeted cell.
The three different cell groups
- Eukaryotes - multicellular or unicellular. This is in plants, animals, protists (algae, fungi, protozoa)
- Eubacteria - prokaryotic - cell chemistry similar to eukaryotes. This is most bacteria including E. coli
- Archaebacteria - prokaryotic, distinctive cell chemistry
The differences between a gram positive and gram negative cell
A gram positive cell has no outer membrane, it has a thicker peptidoglycan layer and chemical composition of cell wall is different from outer membrane of gram negative cell. Gram positive has a cell wall, gram negative does not have a cell wall but rather an outer membrane.
What is peptidoglycan?
Complex polysaccharide with amino acids (gives strength and rigidity)
Features of archaebacteria
They have no peptidoglycan. Nucleotide sequences in ribosomal RNA distinctly different than in eubacteria. Lipid composition of cytoplasmic membrane is very different for the two groups.
Describe the cell wall and which cells have it and which cells do not.
Animal cells have no cell wall which makes them fragile in bioreactor design. Plant cells do have a cell wall, containing peptidoglycan, polysaccharides.
Describe the plasma membrane
This is made up of proteins and a phospholipid bilayer structure). Prokaryotes contain sterols in membrane so stronger and more rigid.
Describe the nucleus
Contains the chromosome as nuclear material surrounded by a membrane
Describe the mitochondria
Powerhouse of eukaryotic cells where respiration and oxidative phosphorylation occurs.
Describe the endoplasmic reticulum
One part contains ribosomes and is responsible for protein synthesis and modification. The other half is responsible for lipid synthesis
