cells Flashcards
def magnification
is the num of the times larger an image is compared to the real size of an object
equ for mag
i/am
def resolution
ability to distinguish two objects close together rather than see them as a single object
what is a nuclear envelope
two membranes that form the outside
what is the nuclear pore
small gaps between, within the envelope
what does nuclear pore do
helps things go in an out (DNA doesn’t leave)
what is mRNA (messenger)
protein synthesis that is a copy of DNA
what two things does mRNA do
leaves through pores
attaches to ribosomes to synthesise (proteins)
what is a nucleolus
where DNA for making ribosomes is found
what is the endoplasmic reticulum
network of membranes
how many types of endoplasmic reticulum
2: RER contains ribosomes, SER lacks ribosomes
what is RER
a continuation of the nuclear envelope
what is a cisterna
a flattened membrane vesicle found in the endoplasmic reticulum and Golgi apparatus
where does protein synthesis take place
RER
is SER cell specific or not
its cell specific
what does SER do
acts as storage organelle (saves ions for later)
what is the Golgi apparatus
A stack of small flat sacs formed by membranes inside the cell’s cytoplasm (gel-like fluid) (pancake shape)
what arear does the membrane surround
area of fluid
where is protein made
in endoplasmic reticulum (ER), vesicles produced
where do vesicles float though
cytoplasm to the golgi ap to be absorbed
what is created and released into the cytoplasm
secretory vesicle
where do vesicles move to
cell membrane and molecules are released out of cell
how many membranes does mitochondria have
2, outer covers organelle, inner folds many times (cristae)
what is a cristae
inner folds of inner membrane (increases surface area)
which membrane does chemical reactions take place inner membrane out outer
inner, increased SA allows small organelles to work more
what is the matrix
fluid inside the mitochondria where DNA is found
what is chloroplast
where protein synthesis takes place (fund in plants and algae)
what is a thylakoid
enclosed third membrane, folded into disks
what is a grana
thylakoid disks that get stacked into piles
what is a stroma
space between inner membrane and thylakoid
Cell surface membrane
what is
what is does
made up of lipids and protein
controls what goes in and out
has receptors to respond to chemicals
mitochondria
what is
what is does
double membrane, matrix (contains enzymes for respiration)
where aerobic respiration takes place, requires a lot of energy
ribosomes
what is
what is does
made up of proteins (not surrounded by membrane)
where proteins are made
lysosome
what is
what is does
round organelle surrounded by membrane
digestive enzymes, kept away from cytoplasm by membrane, break down components out of cell, digest invading cells
nuclear envelope
what is
what is does
maintain shape of nucleus (2nd membrane)
helps regulate flow if molecule in and out pores
golgi apparatus
what is
what is does
fluid filled , membrane bound, flattened sacs with vesicles on edges
processes and packages new proteins and lipids
makes lysosomes
cytoplasm
what is
what is does
gel like substance
most chemical reactions in cells take place
rough endoplasmic reticulum
what is
what is does
system of membranes enclosing fluid filled space covered in ribosomes
folds and processes protein ribosomes have made
nucleolus
what is
what is does
ribosomal synthesis (RNA) produces ribosomes
contains DNA to make ribosomes
nucleus
what is
what is does
large organelle surrounded by nuclear envelope (contains pores)
contains chromatin (made of DNA nd proteins)
DNA has info on making proteins
allows substances (RNA) to move between nucleus and cytoplasm
what is transcription
first stage of protein synthesis in whuch an mRNA copy of gene is made from DNA in the nucleus
DNA stands for
deoxyribonucleic acid, nucleic acid contains pentose sugar deoxyribose
vacuole PL
what is
what is does
organelle that contains cell sap
store water, nutrients and waste material to get rid of them
cell wall PL
what is
what is does
supports plant cells
carbohydrate cellulose, rigid structure
chloroplast PL
what is
what is does
double membrane + thylakoid
forms grana
channel>
,0 PL
what is
what is does
plasmodesmata, intercellular communication
allow molecules to pass from cell to cell (substance exchange)
