Topic 1 Cell Structure Flashcards
Magnification Formula
Magnification=Image/Actual
Calculate EPG (eye piece graticule) in um
100 EPG=0.1mm
100 EPG= 0.1mm
EPG= 0.1/100 (x1000)
EPG= 1um
Difference between magnification and resolution
Magnification- Number of time an image is enlarged compared with the actual size of the object
Resolution- Ability to distinguish between 2 points clearly as seperate
features of an electron microscope
radiation- free electron
wave length- approx. 1nm
max. magnification- x250,000
max. resolution- 0.5 nm
state of specimen- dead
colour- black and white
unit- nm
features of a light microscope
radiation- light
wave length- approx. 400-700nm
max. magnification- x1500
max. resolution- 200 nm
state of specimen- live/dead
colour- coloured
unit- um
Animal cell structure
- cell surface membrane
- nuclues (nuclear envelope, nuclear pore, nucleolus)
- Rough endoplasmic reticulum
- smooth endoplasmic reticulum
- Golgi body
- mitochondria
- ribosome
- lysosome
- centriole
- cillia
- microvilli
Plant cell structure
- cell wall
- cell surface membrane
- nuclues (nuclear envelope, nuclear pore, nucleolus)
- Rough endoplasmic reticulum
- smooth endoplasmic reticulum
- Golgi body
- mitochondria
- ribosome
- lysosome
- chloroplast
- plasmodesmata
- permanent vacuole (tonoplast)
Prokaryotic cell structure
- cell wall
- cell membrane
- cytoplasm
- ribosome (70s)
- circular DNA
- Flagellum
- capsule
- mesosome
- plasmid
- pilli
Cell membrane function
- controlls exchange of material in and out of cells
cell wall function
- fully permeable
- made of cellulose
- structural support for plants
nucleus function
- Contains chromatin (complex of DNA and protein)
nuclear envelope- double membrane
nuclear pore- allow ribosomes to travel out of nucleus
nucleolus- production of ribosomes
Mitochondria function
- site of aerobic respiration
- produce ATP
Chloroplast function
- site of photosynthesis
- contain chlorophyll
Ribosome function
- site of protein synthesis
Rough endoplasmic reticulum function
- processing & transporting ribosomes
Smooth endoplasmic reticulum function
- production, processing, transportation and storage of lipid, carbohydrates and steroids
Golgi body function
- modify protein and package them into vesicles or lysosomes
Vesicle function
- transport
- storage
Permenant Vacuole function
- handle waste products
Lysosome function
- specialist form of vesicles
- break down waste materials
Centriole function
- spincle fibre made of microtubules
- involved in cell division
Microtuble function
- provide support and movement of the cell
microvilli function
- increase in surface area for absorption
cillia function
- allows movement of substances over the cell surface
plasdemodesmata function
- allows direct exchange of substances between membranes
cytoplasm function
- holds internal component of cells
flagellum function
- motion for prokaryotic cell
Capsule function
- extra protection from the immune system
Mesosome function
- may allow photosynthesis
Plasmid function
- small circle of DNA
Pilli function
- for attachment to other cells
- involved in reproduction
Virus features
- non-cellular particles
- between 20-300nm
contains:
- nucleic acid core
- capsid (protects DNA)
Prokeyotic cell features
- unicellular
- generally 1-5um
- peptidoglycan cell walls
- contains 70s Ribosomes
- absence of double-membrane organelles
