Cell: The Unit Of Life Flashcards
What was the contribution of Matthias Schleiden to Cell Theory?
1838, German botanist, studied plant cell and stated that all plants are made of cells and their products
What was the contribution of Theodore Schwann to Cell Theory?
1839,
studied animal cell, reported presence of plasma membrane,
studied plant cell and discovered cell wall
proposed that bodies of animals and plants are composed of cells and their products
What was the contribution of Rudolf Virchow to Cell Theory?
1855,
explained that new cells are formed from pre-existing cells- Omnis cellula-e cellula
What is the size of:
1. RBCs
2. Bacteria
3. Mycoplasma
4. PPLO
- 7 micron
- 3 - 5 micron
- 0.1 - 0.3 micron
- less than 0.1 micron
What is glycocalyx composed of?
polysaccharides, may sometimes contain proteins
What is the cell wall of prokaryotes composed of? How is it affected by penicillin?
It is composed of peptidoglycan(murein or mucopeptide)
Penicillin inhibits cross linking of peptidoglycan strands, cause cell to undergo lysis
What are the functions of mesosome?
Cell wall formation, DNA replication and distribution to daughter cells, respiration, secretion
What is structure of flagellum in prokaryotes? What is its function?
basal body, hook, filament(made of flagellin protein)
function: locomotion and movement
Describe the process of gram staining.
Bacterial smear
Air drying
Stain with crystal violet
Stain with iodine(mordant)- formation of CVI complex
Treatment with alcohol(destaining)
Counter staining with safranin
blue stained - gram positive
pink stained - gram negative
Give three examples of bacteria that have chromatophore.
Cyanobacteria (blue green algae) - Nostoc, Anabaena
Green sulfur bacteria
Purple sulfur bacteria
What are pili made of? In what type of bacteria are they usually found? What is their function?
made of protein pilin
found in gram-negative bacteria
function: formation of conjugation tubule to allow transfer of genetic material between compatible bacteria
What is plasmid?
Plasmid is extrachromosomal, ds circular DNA present in some bacteria.
Flagellum is attached to ____.
Cell wall
Where are ribosomes found in prokaryotes? What is their function in each location?
cytoplasm and plasma membrane
in cytoplasm - they synthesize proteins which remain within the cell
in plasma membrane - they synthesize proteins which are transported out
What is a polysome? What is its function?
When several ribosomes attach to a single mRNA they form a chain called polysome.
Ribosomes of a polysome translate the mRNA into proteins.
