Chapter 4: Cell Structure and Function Flashcards
what is the cell theory?
every cell comes from a preexisting cell
what is the smallest unit of life?
the cell
what are all living things made of?
cells
What do all cells contain?
Plasma membrane
Cytoplasm
Ribosomes
DNA
what is the plasma membrane?
separates the living part of a cell from the non-living environment
what are the two main types of cells?
Prokaryotes and eukaryotes
what are the nucleus types in the types of cells?
pro- no membrane bound nucleus
euk- true nucleus
What is the structure of DNA in prokaryotes?
it is located in the nucleoid, a region of the cytoplasm
it is one large piece of circular DNA
it is naked so it only has a few proteins bound to it (no hisones)
there is no membrane around the DNA
no membrane bound organelles
prokaryotes
no complex internal membranes (no ER or golgi)
prokaryotes
small 79S ribosomes
prokaryotes
most have a cell wall
prokaryotes
reproduce only by binary fission
prokaryotes
some genetic recombination, but rare
prokaryotes
what are the kingdoms and domains for prokaryotic cells?
kingdom monera
Domain bacteria
Domain archaea
what does the domain bacteria contain?
eubacteria and the Cyanobacteria (photosynthetic)
what does the domain archaea contain?
archaebacteria (halophiles, thermophiles, methanogens)
what is the structure of DNA in a eukaryotic cell?
contains a true nucleus with a double membrane
linear DNA arranged in chromosomes
DNA is chromatin- DNA + many proteins
contains many membrane bound organelles
eukaryotes
complex internal membranes present: ER and golgi
eukaryotes
large 80S ribosomes
eukaryotes
binary fission or asexual reproduction (little or no genetic recombination)
sexual reproduction (lots of genetic recombination)
eukaryotes
what domains and kingdoms do eukaryotic cells have?
Domain eukarya
Kingdom Protista
Kingdom fungi
Kingdom plantae
Kingdom animalia
what are kingdoms together if they are very different from each other?
their cell structure is similar to
what are kingdom protistas?
single cell organisms
what is the plasma membranes function in organelles?
regulates entry into and out of the cell
what is the structure of the plasma membrane known as organelles?
phospholipid bilayer with proteins attached and embedded in it
50-50
which organelles are surrounded by a double membrane in a organelle?
nucleus (2 lipid bilayer)
mitochondria
chloroplast
what is the brain of the cell?
nucleus
what is the structure of the nucleus?
double membrane, nuclear pores, nucleolus, DNA in chromatin
what is the function of the nucleus?
stores DNA
DNA replication
RNA synthesis
what are nuclear pores?
controls what goes in and out of the cell
True or false
anything involving DNA has to take place in the nucleus because it can’t leave
True
When is the c chromosome in that shape?
when it divides
what is the cellular energy generator?
mitochondria
what is the cristae?
folded inner membrane, site of electron transport chain
what is the mitochondrial matrix?
liquid part, contains Krebs cycle, DNA, and ribosomes
what is the function of the mitochondria?
cellular respiration ( produces atp to produce energy)
(aerobic respiration breaks down sugars to produce atp)
is the mitochondria semiautonomous?
yes
what is the solar generator?
chloroplast
what are thylakoids?
green photosynthetic membrane (chlorophyll, light reactions)
what is the stroma?
liquid part, contains Calvin cycle, DNA, ribosomes
what are grana (granums)
stacks of thylakoids
what is the function of chloroplast?
photosynthesis, make sugars
how many membranes does chloroplast have?
2
liquid part of chloroplast
liquid part of mitochondria
stroma
matrix
is the chloroplast semiautonomous?
yes
what is the endosymbiont theory?
mitochondria and chloroplasts are derived from small bacteria that were engulfed by larger bacteria during the evolution of eukaryotic cells
what is the evidence for endosymboint theory?
mitochondria, chloroplasts, and bacteria are similar sizes
- all have prokaryotic DNA (circular and prokaryotic gene structure)
all have prokaryotic 60S ribosomes
what contains circular dna, prokaryotic gene structure, and small 60S ribosomes
Mitochondria and chloroplasts
where did the mitochondria originate from?
purple nonsulfur bacteria (aerobic, heterotrophic cells)
what is the advantage of mitochondria’s?
aerobic respiration produces much more energy (atp) than prokaryotes
what is the advantage of mitochondria’s?
aerobic respiration produces much more energy (atp) than prokaryotes
where did chloroplast originate from?
Cyanobacteria (autotrophic cells)
what is the advantage of chloroplasts?
cells can produce its own sugar by photosynthesis
are the mitochondria and chloroplasts free living?
no but they used to be
what organelle is bound by a single membrane?
vacuole
perixisomes
lysosomes
what is a vacuole?
storage and breakdown of substances, turgid pressure in plants
when a plant is dehydrated, where does it lose its water from?
Vacuole
what are perixisomes?
break down peroxide
what are lysosomes?
use acid hydrolysis to break down macromolecules (p, l, na, c)
what is the cells stomach
lysosomes
what do lysosomes contain?
digestive enzymes that break down macromolecules, nutrients and cell parts so they can be used and recycled in the cell
where do vesicles transport substances to be broken down at?
Lysosomes
what are ribosomes structure?
large subunit and small subunit
made of 50% rRNA and 50% protein (no membrane)
what is the function of ribosomes?
protein synthesis
what is the location of ribosomes?
cytoplasm and rough ER
what is in the endomembrane system?
smooth ER
rough ER
golgi
vesicles
lysosomes
endomembrane system is where in the cell
In
what is the structure of the smooth ER
tubular sheets of membranes continuous with rough ER, no ribosomes
what is the function of the smooth ER?
lipid and membrane synthesis- main function
Ca++ storage - muscle cells
detoxification - liver cells
carbohydrate metabolism
what is the structure of the rough ER?
sheets of membrane, contains ribosomes on surface
is continuous with nuclear membrane
what is the function of the rough ER?
protein synthesis
insertion (embedded) of proteins into membrane
gulcosylation: add sugars to certain proteins
what is the packaging and shipping center?
Golgi
what is the structure of the Golgi?
stacks of membranes
what is the lumen of the golgi?
area enclosed by Golgi membrane
what way do the ends of the Golgi face?
One faces rough ER and other faces plasma membrane
where are proteins in the Golgi received from?
Rough ER
in the Golgi are proteins modified
yes : sugars are attached to proteins (glycoaylation)
different chemical reactions take place in each stack so proteins are modified
what happens to proteins in the Golgi?
sorted based on tags
packed into vesicles depending on where they go
sent to their final location in the cell
what are vesicles?
small membrane sacs that transport substances between membranes or organelles
proteins made in the rough ER are sent to the
golgi
where is the ER lumen?
the area inside of the tube which is formed by the er membrane
proteins in the lumen of the ER are packed in
Vesicles
protein sorting in Golgi
where are proteins sent
Plasma membrane or lysosomes
what is intracellular transport?
proteins being sent and moved
what is the cytoskeleton?
network of molecules inside the cell
what is the cytoskeleton composed of?
actin filaments
Intermediate filaments
microtubules
what is the function of cytoskeleton?
gives structure to the cell and organelles
Involved in intracellular transport
Involved in cell movement
what are actin filaments?
made of actin, a long fibrous protein
where is actin usually found?
beneath plasma membrane and it gives shape to the cell
what is actin involved in?
cell movement
what are intermediate filaments?
are very strong and form a general scaffold inside the cell
can many different proteins form intermediate filaments?
ysa
what are microtubules?
hollow tubes made of tubular proteins
spindle fibers
what are microtubules involved in?
intracellular movement
what are microtubules components of?
flagella
what is intracellular movements?
track: microtubules
motor proteins: walks along track, carries cargo
cargo: vesicle, chromosome
what do motor proteins do?
tow vesicles along the microtubule highway in cytoskeleton
It uses atp everytime it steps
what do cilia and flagella contain?
microtubules
what do cilia and flagella move?
cell through liquid
air or water across a surface
size of cilia?
short and a ton of them
size of flagella?
longer and only a couple
what are cilia and flagella covered by?
plasma membrane
what is cilia and flagella’s inner core?
microtubules
what is a cell wall?
gives structure to cell not a barrier so anything can go in and out
where are cell walls located
outside of plasma membrane
what is middle lamella?
glue some cell to adjacent cell
what cells don’t have a cell wall
animal
what is the cell wall composed of?
cellulose
Protein
Sugars
what is the middle lamella made of?
calcium pectate/pectin
where is the animal extracellular matrix located? ECM
outside of plasma membrane
what is the animal ECM made of?
proteins and carbohydrates (proteoglycan)
why are plants more like animal cells?
both are eukaryotic, so are more alike than bacteria
they have the characteristics of a eukaryotic cell
plant eukaryotic cells contain
Nucleus, linear dna in chromosomes, chromatin, mitochondria and other organelles, large 80s ribosomes, RER, SER, Golgi, cytoskeleton, and plasma membrane
what structures are only in plant cells?
cell wall
chloroplast
large central vacuole (start little but fuse together)
what structures are found in all plant cells?
cell wall, mitochondria
chloroplast (only in some cells in green photosynthetic tissue, not roots, stems, flowers), large central vacuoles (only in mature cells not young dividing cells), and plasmodesmata
what is plasmodestmata?
cytoplasmic connections between cells
how cells communicate
do all plant cells have lysosome?
What are sorting signals?
short amino acid sequences that direct where proteins go
where is cholesterol with the cell?
near the fatty acid tails
What is mosaic, semipermeable, fluid, sided?
Membrane
which cell?
vacuoles
Plant and animal
which cell?
peroxisomes
Plant and animals
Lysosomes
Plant and animal