1.1 cell biology Flashcards
cell theory states that
- all living organisms are made of one or more cells
- the cell is the basic unit of structure and organization in organisms
- all cells come from other cells
what are 3 exceptions to cell theory?
Striated muscle fibres, Aseptate fungal hyphae, and giant algae
why are striated muscle fibers an exception to cell theory?
- Muscle cells fuse to form very long fibres (>300mm)
- multi-nucleated
- Challenges the idea that cells always function as autonomous units
why is Aseptate fungal hyphae an exception to cell theory?
- continuous cytoplasm
- challenges the idea that cells are individual units
why is giant algae an exception to cell theory?
- giant, grow up to 100mm in length w only 1 nucleus
- challenges the idea that larger organisms are always made of many microscopic cells
acronym for functions of life
mr h gren
functions of life
metabolism
response
homeostasis
growth
reproduction
excretion
nutrition
metabolism
all the enzyme-catalyzed reactions in the cell or organism. this includes respiration
response
the ability to respond to and interact with the environment
homeostasis
the maintenance and regulation of internal cell conditions
growth
changing size/shape
reproduction
producing offspring by sexual or asexual reproduction
excretion
the removal of metabolic waste
nutrition
obtaining organic molecules via absorption (eg feeding) or synthesis (eg photosynthesis)
heterotroph
an organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter (consumers, not producers)
functions of life in paramecium
M - metabolic reactions mostly in cytoplasm, respiration in mitochondria
R - cilia feel particles in the surrounding environment
H - contractile vacuole regulate water content by expelling water from the cell membrane
G - gain biomass
R - cell division (mitosis)
E - the cell membrane regulates excretion. vesicles release materials (exocytosis)
N - the cell membrane surrounds food and takes it into the cell (endocytosis)
paramecium
genus of unicellular heterotroph protozoans
chlorella
photosynthetic unicellular organism