B1.1 what is in cells? Flashcards
sub-cellular structures
structures found in cells
-mitochondria
-ribosomes
-cytoplasm
-cell membrane
-chloroplast
-nucleus
nucleus
the control center of the cell
cytoplasm
where chemical reactions take place (in living cells)
cell membrane
a layer that holds the cytoplasm in a cell and controls what enters or leaves the cell
mitochondria
structures in the cytoplasm where energy is produced from chemical reactions
ribosomes
small structures found in the cytoplasm of living cells where protein synthesis takes place
cell wall
a protective layer found outside the cell membrane of a plant, fungal and bacterial cells. it helps support the cells
cellulose
a carbohydrate that makes up the cell wall of plants
vacuole
a fluid-filled hole inside a cell that is used for storage and support
containing cell sap
chloroplast
a structure that contains chlorophyll (which makes it green). it is found in algae and plants that carry out photosynthesis
prokaryotic cells
(bacteria, protists, fungi) that don’t have a nucleus or organelles (like mitochondria)
eukaryotic cells
cells that have a nucleus and sub-cellular organelles (like mitochondrial)
plasmid
a small circle of DNA in prokaryotic cells (instead of a nucleus)
resolution
the smallest distance apart 2 objects can be and still be seen as seperate objects
electron microscope
a device that fires electrons at a specimen to obtain a high resolution image
magnification
how many times larger an image is then the actual object
agar
a jelly made from algae that is used to culture microorganisms
culture
a substance that provides the nutrients for the artificial growth of bacteria and other cells
petri dish
a round shallow dish used to grow bacteria
chromosomes
a long molecule found in the nucleus of all cells, made from DNA
DNA
molecules which contain genetic information and make up chromosomes
cell cycle
the series of growth and division events that a cell goes through during its lifetime
undifferentiated
a cell that has not yet become specialised (carry out a specific job)
surface area to volume ratio
a way of comparing the surface area of an organism to its volume - the smaller this ratio the harder it is to exchange substances with the environment at a fast enough rate
factors of light microscopes
cheap
shows living cells
low resolution
factors of electron microscopes
expensive
shows dead cells
high resolution
magnification equation
size of the real object
mm
Mm size in meters 10^
nm
mm= 10^-3
Mm=10^-6
nm=10^-9
why are muscle cells specialised
protein fibres(to contract)
lots of mitochondria for energy
how are sperm cells specialized
flagella
acrosome(to penetrate egg)
lots of mitochondria
how are red blood cells specialized?
no nucleus(for more space to carry oxygen)
contain haemoglobin( which binds to oxygen)
small(to fit through narrow vessels)
how are white blood cells specialized?
Irregular shape(to get to infections faster)
how do white blood cells engulf substances?
surrounding then destroying the substance
