Organelles Flashcards
organelles are membrane-bound compartments within the cell that have –
specialized functions
organelles help with cellular organization and – by ensuring that specific reactions have specific organelles in which to occur
efficiency
organelles and other structures, but not the – are contained within the cytoplasm
nucleus
cytoplasm encompasses the space between the – and the nucleus
plasma membrane
liquid portion of the cell
cytosol
cytosol consists of water, –, ions, and waste and it can be the site of a variety of chemical reactions within the cell
nutrients
all eukaryotic cells contain a membrane-bound nucleus that houses the genetic material in form of –
chromosomes
outer boundary of the nucleus is referred to as the – and keeps the contents of the nucleus separate from the rest of the cell
nuclear membrane/envelope
nuclear membrane has – that allow certain substances to enter and exit the nucleus
pores
make the ribosomal ribonucleic acid (rRNA) needed to produce ribosomes
nucleolus
ribosomes are made from rRNA and –
protein
a ribosomes consists of one large subunit and one small subunit that are assembled when – is needed
protein synthesis
ribosomes can be found loose in the –
cytosol
free ribosomes and membrane-bound ribosomes are identical in structure and function but they differ in the – that are being made
proteins
make proteins that are destined to function in the cytosol, mitochondria, chloroplast or nucleus
free ribosomes
make proteins that will be translocated into the ER lumen or into the ER membrane (depending on the protein structure) and either function within the ER membrane, lumen of an organelle or can be released
membrane-bound ribosomes
consists of several organelles within the eukaryotic cell that work together as a unit to synthesize and transport molecules within the cell
endomembrane system
folded network of membrane-bound space that has the appearance of a maze
endoplasmic reticulum (ER)
rough ER has – on the surface
bound ribosomes
while the rough and smooth ERs are – their functions are distinct
connected
produce lipids needed by the cell
smooth ER
in the liver, smooth ER produces –
detoxifying enzymes
ribosomes produce proteins that enter the rough ER where they will be – and moved to the smooth ER
chemically modified
the combined contents of the smooth and rough ER are then shipped by vesicles to the – for sorting
Golgi complex
tiny pieces of membrane that will break off and carry the contents of the ER throughout the endomembrane system
vesicles
in the Golgi complex, molecules are further modified, repackaged, and – for their eventual destination
tagged
contents of the Golgi complex leave via vesicles and many of them will be moved to the – for secretion out of the cell
cell membrane
large, membrane-bound sacs that contain digestive enzymes used to break down any substances that enter it
lysosomes
process of cells taking in molecules by enclosing them in a vesicle pinched off of the cell membrane
endocytosis
pH of lysosome must be –
acidic
lysosomes contain – H+ pumps that pump H+ ions into the lysosome, causing it to become more acidic
ATP driven
lysosomes’ membrane proteins are highly – to protect them from proteases
glycosylated
in some cases, cells purposefully rupture their lysosomes in an attempt to commit cellular suicide in a process known as –
apoptosis
type of vacuole found within the endomembrane system that digest fatty acids and amino acids
peroxisomes
peroxisomes can also degrade – a metabolic waste product to water and oxygen gas
hydrogen peroxide
energy producing organelle
mitochondria
mitochondria have an inner and outer membrane and contain their own – distinct from the one in the nucleus
DNA
T/F: mitochondria can self-replicate
true
– is composed of three types of fibers that exist within the cytoplasm
cytoskeleton
one type of hollow fiber, made of the protein tubulin, that is responsible for structural support and the maintenance of cell shape
microtubules
microtubules also provide – that allow for the movement of organelles within the cell
tracks
during cell division, – are used to help direct chromosomes through the cell
microtubules
made of protein actin, they assist with cellular movement
microfilaments
the – of filaments vary from one cell type to the next
composition
typically form a network throughout the cytoplasm and are anchored at the plasma membrane at specific points where the – from one cell is in contact with the - from another
intermediate filament
primary purpose of the intermediate filaments is – for the cell
four classes of structural support
four class of intermediate filaments = keratin filaments, vimentin filaments, neurofilaments, and –
nuclear lamins
hairlike structures on the surface of some cells that move in synchronized motion
cilia
cilia on the surface of cells lining the respiratory tract constantly – in an attempt to catch and remove bacteria and particles that may enter the respiratory tract
move
some animal cells, such as sperm, which essentially act as tails to allow for movement
flagella
plant cell wall is composed of – and serves to protect the cell from its environment and from desiccation
cellulose fiber
chloroplasts are similar to mitochondria in that they have their own DNA and –
replicate independently
plant cell’s reserve storage for water, nutrients, and waste products
large central vacuole
T/F: central vacuole typically takes up the majority of space within a plant cell
true
purpose of the cell (plasma) membrane to form a – barrier between the cell and its outside environment
selectively permeable
membrane is composed of a phospholipid bilayer scattered with –
proteins
phospholipid head is composed of a glycerol and – that carries a charge
phosphate group
phospholipid head is
hydrophilic
tails of the phospholipid are composed of – that are not charged and are hydrophobic
fatty acids
phospholipids – arrange themselves in a bilayer where the heads align themselves towards the inside and outside of the cell where water is located
spontaneously
phospholipids are dynamic and rapidly move – within within one plane of the membrane
laterally
phospholipids will rarely – to the opposite plane which is energetically unfavorable
flip
there are proteins called – that will flip a phospholipid from one plane to the other if this is required by the cell
flippases
T/F: many molecules are capable of moving through the plasma membrane
true
T/F: nonpolar molecules can travel across the plasma membrane
true
while O2 and N2 are easily cross the membrane because they are – and –
small and nonpolar
ethanol and water are also able to cross the membrane even though they are –
polar
the more important factor in determining whether or not a molecule will cross the lipid bilayer, in addition to the size limitation, is the – of the molecule
charge
charged molecules and – will not pass through the bilayer regardless of size
ions
K+, Na+, Ca2+, and Cl- will not pass through the membrane without the aid of a – or transporter even though they are smaller than O2, N2, ethanol, and water
protein channel
regulates the fluidity of the membrane
cholesterol
proteins within the cell membrane that contain carbohydrates on the surface
glycoproteins
lipids within the cell membrane that contain carbohydrates on the surface
glycolipids
glycoproteins and glycolipids often serve as identifying markers or – for the cell
antigens
