BIO 183 CH 4 - Cell Structure
four components are required to move material along microtubules:
1. a vesicle or organelle that is to be transported 2. a motor protein that provides the energy driven motion 3. a connector molecule that connects the vesicle to the motor molecule 4. microtubules on which the vesicle will ride like a train on a rail
eukaryotic cells may contain the following three types of cytoskeletal fibers, each formed from a different kind of subunit
1. actin filaments (microfilaments) 2. microtubules 3. intermediate filaments
what is the cell theory (3)
1. all organisms are composed of one or more cells and the life processes of metabolism and heredity occur within these cells 2. cells are the smallest living things 3. cells arise only from preexisting cells
what are the 3 types of fibers of the cytoskeleton
1. microfilaments 2. microtubules 3. intermediate filaments
four main features all cells have in common
1. nuclei of nucleus where genetic info is located 2. cytoplasm 3. ribosomes to synthesize proteins 4. a plasma membrane
objects must be _______ micrometers apart for the naked eye to resolve them
100
the ________ structure of flagella and cilia appears to be a fundamental component of eukaryotic cells
9+2
on the surface of the inner membrane of the mitochondria and also embedded within it are proteins that carry out the oxygen requiring process by which energy in macromolecules is used to produce _____
ATP
an important function of the SER is to store intracellular _____
Ca^2+
Schlseiden and Schwann proposed the
Cell theory
package DNA
Chromosomes
contains the genes that code for the proteins synthesized by the cell
DNA
the very structure of chromatin affects the function of _____
DNA
interns allow the _____ to influence cell behavior in important ways like altering gene expression and cell migration patterns by a combination of mechanical and chemical signaling pathways.
ECM
all eukaryotic cells must move materials from one place to another in the cytoplasm and one way cells do this is by using the channels of the _______ as an intracellular highway or using vesicles loaded with cargo that can move along the cytoskeleton like a railroad track
ER
many peroxisomal proteins are synthesized by cytoplasmic ribosomes and can also form from the fusion of ___-dervied vesicles
ER
the _____ is composed of a phospholipid bilayer embedded with proteins
ER
the sequence of the protein being synthesized determines whether the ribosome will become associated with the _____ or remain a cytoplasmic ribosome
ER
_____ proteins-recognition of "self" and "nonself" cells by the immune system
MHC
most eukaryotic cells possess ____________ nucleus, but some cells of fungi and other groups may have ____________
a single, several to many
__________ filaments play a major role in determining the shape of cells because they can form and dissolve so readily
actin
at the leading edge of a crawling cell, ________ filaments rapidly polymerize, and their extension forces the edge of the cell forward
actin
_________ are long fibers (about 7nm in diameter) composed of two protein chains loosely twined together like two strands of pearls with one positive and one negative end, each "pearl" or subunit on the chain is the globular protein ______
actin filaments, actin
essentially all cell motion is tied to the movement of ________ ______, _____________, or both
actin filaments, microtubules
essentially all cell motion is tied to the movement of ___________, _____________ or both
actin filaments, microtubules
_____________ junctions are based on the protein cadherin, found in animals ranging from jelly fish to vertebrates
adherens
_________ junctions were the first to evolve, found in all animal species, mechanically attach the cytoskeleton of a cell to the cytoskeletons of other cells or the ECM
adhesive
organism made of many small cells has an advantage/disadvantage over an organism composed of fewer, larger cells
advantage
various chemical compounds, including polysaccharides and proteins and even possibly inorganic components compose the cell walls of _______
archaea
the microtubules of the flagellum are derived from a ________ _________ situated just below the point where the flagellum protrudes from the surface of the cell
basal body
enzymes anchored within the ER are involved in the synthesis of a variety of _______ and ________
carbs and lipids
peroxisomes contain the enzyme ________ which breaks down hydrogen peroxide into water and oxygen
catalase
ratio of RER to SER depends on
cell function
the membrane surrounding the cell plays a key role in controlling _______________
cell function
protect the cell, maintain its shape, and prevent excessive uptake or loss of water
cell wall
strength and shape of the cell is determined by the __________ and influenced by the ____________
cell wall, cytoskeleton
the susceptibility of bacteria to antibiotics often depends on the structure of their _________
cell walls
in plants and protist the cell walls are composed of fibers of the polysaccharide _________, whereas in fungi the cell walls are composed of ________
cellulose, chitin
plant cells often have a large, membrane bounded sac called
central vacuole
the ________ _____ is also involved in cell growth by occupying most of the volume of the cell
central vacuole
the _________ _________ allows the cell to expand and contract since it maintains tonicity
central vacuole
the different types of vacuoles include _________ vacuole in plant cells, ___________ vacuole of some fungi and protists, and ________ vacuoles
central, contractile, storage
animal cells and most protists have __________ while plants and fungi usually lack them
centrioles
barrel shaped organelles found in the cells of animals and most protists, occur in pairs usually located at right angles to each other near the nuclear membranes
centrioles
the centrosomes of plants and fungi lack _________, but still contain microtubule organizing centers
centrioles
the _______ is also responsible for the reorganization of microtubules that occurs during cell division (along with microtubule organizing centers)
centrosome
the region surrounding the pair in almost all animal cells is referred to as a ______
centrosome
______ are microtubule organizing centers
centrosomes
region surrounding centrioles in almost all animal cells
centrosomes
mitochondria and _______ share structural and function similarities, which include both surrounded by a double membrane, contain their own DNA and protein synthesis machinery. functionally they are both involved in energy metabolism
chloroplasts
organelles present in cells of plants and some other eukaryotes that contain chlorophyll for photosynthesis
chloroplasts
plant cells and cells of other eukaryotic organisms that carry out photosynthesis typically contain from one to several hundred ________
chloroplasts
surrounded by 2 membranes and have their own RNA
chloroplasts
the chloroplast is surrounded by __ membranes, but is more complex than mitochondria
chloroplasts
in eukaryotes the dna is divided into multiple linear chromosomes which are organized with proteins into a complex structure called
chromatin
inside the nucleus the DNA is wound tightly around proteins and packaged into compact until called
chromosomes
short cellular projections that are often organized in rows, more numerous than flagella on the cell surface but with the same internal structure
cilia
the front/receiving end of the golgi, called the _____ face, is usually located near the ER
cis
the golgi apparatus has _____ and _____ faces
cis and trans
the individual stacks of membrane of the golgi body are called ________ and they vary in number from 1 or a few in the protists , to 20 or more in animal cells and to several hundred in plant cells
cisternae
_____________ junctions allow communication between cells by diffusion through small openings
communicating
achieved through use of membrane bound organelles and endomembrane system in cells
compartmentalization
the endomembrane system divides the cell into _____________ where different cellular functions occur
compartments
the _______ vacuole in found in some protists and can pump water and is used to maintain water balance in the cell
contractile
the arrangement of actin filaments within the cell cytoplasm allow cells to ________
crawl
_________ is a significant cellular phenomenon, essential to such diverse processes as inflammation, clotting, wound healing and the spread of cancer (white blood cells in particular exhibit this ability
crawling
the inner folded membrane of mitochondria with numerous contiguous layers is called
cristae
semifluid matrix fills the interior of the cell and contains all of the sugars, amino acids and proteins the cell uses to carry out its everyday activities
cytoplasm
the material within a cell, excluding the nucleus
cytoplasm
all eukaryotic cells are supported by an internal protein scaffold
cytoskeleton
by moving and anchoring particular enzymes near one another, the ____________, like the ER, helps organize the cell's activities
cytoskeleton
network of protein fibers found in all eukaryotic cells that supports the shape of the cell and keeps organelles in fixed location
cytoskeleton
the ________ is responsible for the cell's shape and movement, but it also provides a scaffold that holds certain enzymes and other macromolecules in defined areas of the cytoplasm
cytoskeleton
the cytoplasm of all eukaryotic cells is crisscrossed by a network of protein fibers that supports the shape of the cell and anchors organelles to fixed locations
cytoskeleton
this network is a dynamic system, constantly assembling and disassembling
cytoskeleton
the fluid portion of the cytoplasm that contains dissolved organic molecules and ions
cytosol
the part of the cytoplasm that contains organic molecules and ions in solution is call the _________ to distinguish it from the larger organelles suspended in this fluid
cytosol
the two largest compartments of in eukaryotic cells are the inner region of the ER which is called cisternal space or ________ and the region exterior to it ___________ which is the fluid component of the cytoplasm
cytosol
________ are a cadherin-based junction unique to vertebrates, join adjacent cells and these connections support tissues against mechanical stress
desmosomes
most cells are relatively small due to reliance on _____________ of substances in and out of cells
diffusion
the rate at which transport of molecules and waste occurs depends on both the _________ to the membrane and the ________ of the membrane available, which is why organisms made up of smaller cells have advantage over one composed of fewer, larger cells
distance, area
the cytoskeleton is a _________ system, constantly forming and disassembling
dynamic
one of the fundamental distinctions between eukaryotes and prokaryotes is the
endomembrane system
series of membranes throughout the cytoplasm
endomembrane system
the outer membrane of the nuclear envelope is continuous with the cytoplasms interior membrane system, called the _____ _______
endoplasmic reticulum
the largest of the internal membranes is the
endoplasmic reticulum (ER)
mitochondria and chloroplasts arose by
endosymbiosis
one cell, a prokaryote, was engulfed by and became part of another cell, which was the precursor of modern eukaryotes
endosymbiosis
proposes that some of today's eukaryotic organelles evolved by a symbiosis arising between 2 cells that were each free living
endosymbiosis
theory of ___________ proposes that some of today's eukaryotic organelles evolved by a symbiosis arising between two cells that were each free living
endosymbiosis
the membranes of the SER contain many embedded
enzymes
the cellular machinery that replicates DNA and synthesized proteins in archaea is more closely related to bacterial or eukaryotic systems?
eukaryotic
process a membrane bound nucleus, more complex, hallmark is compartmentalization, possess a cytoskeleton for support and to maintain cellular structure
eukaryotic cells
____________ are usually 10-100 micrometers in diameter but __________ are usually 1-10
eukaryotic, prokaryotic
the proteins synthesized on the surface of the RER are destine to be _______ from the cell, sent to ________ or _________, or embedded in the __________ __________
exported, lysosomes, vacuoles, plasma membrane
chromatin is usually in a more ___ form that is organized in the nucleus. when cells divide the chromatin must be ______ into a more highly condensed state that forms the X shaped chromosomes visible in the light microscope
extended, compacted
animal cells lack the cell walls that encase plants, fungi and most protists. instead animal cells secrete an elaborate mixture of glycoproteins into the space around them, forming the
extracellular matrix (ECM)
the fibrous protein ________ (same protein found in cartilage, tendons and ligaments) may be abundant in the
extracellular matrix (ECM)
long, threadlike structures protruding from the surface of the cell that are used in locomotion
flagella
___________ and _________ have a 9+2 arrangement of microtubules
flagella and cilia
as pairs of microtubules move past each other using arms composed of the motor protein dyne, the eukaryotic _________ undulates (waves up and down)
flagellum
the rotary motor uses the energy stored in a gradient that transfers protons across the plasma membrane to power the movement of the _________ (this same principle is used in eukaryotic mitochondria and chloroplasts)
flagellum
_____ ribosomes synthesize proteins that are found in the cytoplasm, nuclear proteins mitochondria proteins and proteins found in other organelles not derived from the endomembrane system
free
vacuoles are specialized depending on the ________
function of the cell
_________ proteins consisting of dimers of alpha and beta tubular subunits polymerize to form the 13 protofilaments that make up microtubules
globular
the _______ (tissue specific cell surface markers) on the surface of red blood cells are responsible for the A, B and O blood types
glycolipids
in the ER newly synthesized proteins can be modified by the addition of a short-chain carbohydrates to form _______
glycoproteins
most common alteration when passing through the golgi is the addition or modification of short sugar chains, forming __________ and _______
glycoproteins and glycolipids
another function of the ______ ______ is the synthesis of cell-wall components
golgi apparatus
vesicles transport molecules to destination for what
golgi apparatus
flattened stacks of interconnected membranes are
golgi bodies
flattened stacks of membranes form a complex called the
golgi body or golgi apparatus
chloroplasts have closed compartments of stacked membranes called ______ which lie inside the inner membrane
grana
larger cells need to synthesize more macromolecules, and have lower/higher energy requirements and waste
higher
surface proteins give cells _________
identity
as the size of a cell increases, the length of time for diffusion from the outside membrane to the interior of the cell ____________
increases
this structure gives the nucleus its shape and is also involved in the deconstruction and reconstruction of the nuclear envelope that accompanies cell division
inner surface of the nuclear envelope
fibronectin molecules bind not only to ECM glycoproteins but also to proteins called ________, which are an integral part of the plasma membrane, extending into the cytoplasm where they are attached to the microfilaments and intermediate filaments of the cytoskeleton
integrins
______________ filaments act as intracellular tendons, preventing excessive stretching of cells
intermediate
between the size of actin filaments and microtubules, very stable - usually not broken down (cytoskeleton fiber)
intermediate filaments
once formed, __________ ________ are stable and usually do not break down
intermediate filaments
the most durable element of the cytoskeleton in animal cells is a system of tough, fibrous protein molecules twined together in an overlapping arrangement (8 to 10 nm in diameter)
intermediate filaments
the inner surface of the nuclear envelope is covered with a network of fibers that make up the nuclear _________ which is composed of intermediate filament fibers called nuclear lamins
lamina
a common feature distinguishing archaea from bacteria is the nature of their membrane ________
lipids
the majority of membrane ________ are assembled in the SER and then sent to whatever parts of the cell need membrane components
lipids
_______ cells have extensive SER as well as enzymes that can process a variety of substances by chemically modifying them
liver
______ are activated by fusing with a food vesicle produced by phagocytosis or by fusing with an old or worn out organelle
lysosomes
_______ contain high levels of degrading enzymes which catalyze the rapid breakdown of proteins, nucleic acids, lipids and carbs to make room for newly formed organelles
lysosomes
___________ are responsible for enzymes catalyze breakdown of macromolecules
lysosomes
membrane bound digestive vesicles ___________, are also components of the endomembrane system and arise from the golgi apparatus
lysosomes
membrane bounded digestive vesicles that arise from golgi apparatus
lysosomes
where are proteins sent to after protein synthesis occurs in the endoplasmic reticulum (2)
lysosomes or plasma membrane
________ destroy cells or foreign matter that the cell has engulfed by _____________
lysosomes, phagocytosis
besides ribosomes, protein synthesis also requires
mRNA and tRNA
receptor proteins can function as _______ that identify the cell as a particular type
markers
the cristae partition the mitochondrion into two compartments:
matrix (lies inside the inner membrane) and inter membrane system (outer compartment the lies between the two mitochondrial membranes)
______-associated ribosomes synthesize membrane proteins, proteins found in the endomembrane system and proteins destined for export from the cell
membrane
molecules used for energy and biosynthesis must be transported through the ___________, along with any metabolic waste that needs to be removed
membrane
the distribution of enzymes to ______ (found in the cells of plants, animals, fungi and protists) is one of the principle ways eukaryotic cells organize their metabolism
microbodies
variety of enzyme-bearing, membrane-enclosed vesicles
microbodies
actin filament, 2 protein chains loosely twined together, movements like contraction, crawling, pinching (cytoskeleton fiber)
microfilament
largest of the cytoskeleton elements, demers of alpha and beta tubular subunits, facilitate movement of cell and materials within cell
microtubule
___________ (cytoskeletal fiber) are in a constant state of flux, continually polymerizing and depolymerizing
microtubules
the largest of the cytoskeletal elements are hollow tubes about 25 nm in diameter each composed of a ring of 13 protein protofilaments
microtubules
______ have their own DNA and basically acts as a cell within a cell, but is not autonomous because most of the genes that encode the enzymes used in oxidative metabolism are located in the cell nucleus
mitochondria
found in all types of eukaryotic cells, bound by membranes, the inner membrane has cristae, and a matrix
mitochondria
on the surface of the inner membrane and also embedded within it are proteins that carry out oxidative metabolism
mitochondria
typically tubular or sausage shaped organelles, bounded by two membranes
mitochondria
what has it's own DNA
mitochondria
two key eukaryotic organelles are believed to be the descendants of endosymbiotic prokaryotes:
mitochondria and chloroplasts
___________ feature of archaea confer greater thermal stability, with the trade off of not being able to adapt to changing environmental temperatures
monolayer
chemical structure of archaeal lipids can include saturated hydrocarbons that are covalently attached to glycerol at both ends, such that their membrane is a __________
monolayer
__________ motors along the actin filaments contract, pulling the contents of the cell toward the newly extended front edge
myosin
overall forward movement of the cell is then achieved through the action of the protein __________, which is best known for its role in muscle contraction
myosin
some cells overcome limitation by being long and skinny like _______
neurons
DNA in a cell's nucleus encodes the amino acid sequence of each protein in the cell, are proteins assembled in the nucleus? yes or no
no
the surface of the nucleus is bounded by two phospholipid bilayer membranes which together make up the _______ ________
nuclear envelope
scattered over the surface of the nuclear envelope are what appear as shallow depressions in the electron micrograph but are in fact structures called _______ _______
nuclear pores
in many cells microtubules form from _______ centers near the center of the cell and radiate toward the periphery
nucleation
many nuclei exhibit a dark-staining zone called the ________ which is a region where intensive synthesis of ribosomal RNA is taking place
nucleolus
region where ribosomal RNA synthesis takes place
nucleolus
___________ is the repository of genetic information
nucleus
most eukaryotic cells posses a single ________
nucleus
skeletal muscle cells have more than one ________, allowing genetic information to be spread around a large cell
nucleus
the ________ is the repository of the genetic info that enables the synthesis of nearly all proteins of a living eukaryotic cell
nucleus
the largest and most easily seen organelle within a eukaryotic cell is the _____, roughly spherical in shape and typically located in the central region of the cell in animal cells
nucleus
we call any discrete macromolecular structure in the cytoplasm specialized for a particular function _________
organelle
protein synthesis is associated with large RNA-protein complexes (ribosomes) outside/inside the nucleus
outside
golgi apparatus functions in _____________ and _____________ of molecules synthesized at one location and used at another within the cell or even outside of it
packing and distribution
the _______ _______ of a prokaryotic cell carries out some of the functions organelles perform in eukaryotic cells
plasma membrane
the ____________ ___________ encloses a cell and separated its contents from its surroundings
plasma membrane
cytoplasmic connections that form across the touching plasma membranes
plasmodesmata
organelles- chloroplasts, leucoplasts and amylosplasus are collectively called _____ and all of these are produced by the division of existing _____ (same)
plastids
the direction a vesicle is moved depends on the type of motor protein involved and the fact that microtubules are organized with their plus/negative ends toward the periphery of the cell
plus
cells regulate the rate of actin __________ through other proteins that act as switches.
polymerization
the ________ allows ions and small molecules to diffuse freely between nucleoplasm and cytoplasm while controlling the passage of proteins and RNA-protein complexes (in the nuclear envelope)
pore
in plants, __________ walls are laid down when the cell is still growing. between the walls of adjacent cells a sticky substance, the ____________ _________ glues the cell together. some plant cells produce ________ walls which are deposited inside the primary walls of fully expanded cells
primary, middle lamella, secondary
_________ are the simplest organisms
prokaryotes
are small, consist of a cytoplasm surrounded by a plasma membrane and are encased within a rigid cell wall with no distinct interior compartments
prokaryotes
archaea share a similar overall cellular architecture with _________ but are more closely related to _____ on a molecular basic
prokaryotes, eukaryotes
____________ flagella are protein fibers that extend out from the cell
prokaryotic
simplest organisms, lack a membrane-bound nucleus, DNA present in the nucleiod, do not contain ribosomes, cell wall outside of plasma membrane
prokaryotic cells
the destination of a particular transport vesicle and its content is determined by the nature of the linking ________ embedded within the vesicle's membrane
protein
cytoplasm is more like jello than water due to the high concentration of ________ and other macromolecules
proteins
_______ and ______ manufactured on the rough and smooth ER membranes are transported into the golgi apparatus and modified as they pass through it
proteins and lipids
transport across the pore is controlled and consists mainly of the import of _______ that function in the nucleus and the export to the cytoplasm of _____ and _____-protein complexes formed in the nucleus
proteins, RNA, RNA
the _________ embedded in the plasma membrane are generally responsible for a cell's ability to ______
proteins, interact with the environment
____________ proteins induce changes within the cell when they come in contact with specific molecules in the environment, such as hormones or with molecules on the surface of neighboring cells
receptor
mammalian erythrocytes (____________) lose their nuclei when they mature
red blood cells
the minimum distance 2 points can be apart and still be distinguished as two separate points
resolution
in vertebrae individual golgi are linked to form a golgi _______, that are abundant in glandular cells which manufacture and secrete substances
ribbon
__________ are among the most complex molecular assemblies found in cell, each being composed of two subunits, each of which is composed of a combination of RNA and proteins. these subunits join to form a functional ___________ (same) only when they are actively synthesizing proteins
ribosomes
_______________ may be free in cytoplasm or associated with internal membranes
ribosomes
before cells can synthesize proteins in large quantity, they must first construct a large number of ___________ to carry out this synthesis
ribosomes
factories that make proteins
ribosomes
found in all cell types and in all 3 domains
ribosomes
prokaryotic cells do contain organelles like __________, but most are not membrane bound like eukaryotic
ribosomes
_____________ endoplasmic reticulum has the attachment of ribosomes to the membrane and deals with the synthesis of proteins to be secreted
rough
cells that synthesize proteins that are secreted, such as antibodies, have such more extensive _____ ER
rough
beams electrons onto the surface of the specimen, producing 3D images
scanning electron microscope (SEM)
__________ junctions are found in both invertebrates and vertebrates and form a barrier that can seal off a sheet of cells
separate
electrons have a much shorter/longer wavelength than light, which is why electron microscopes have 1000 times the resolving power of a light microscope
shorter
storage of intracellular Ca^2+ keep the cytoplasmic level low, allowing Ca^2+ to be used as a _________ molecule
signaling
control over cell contents is more effective when cells are relatively small/large
small because more surface area per unit of volume
______________ endoplasmic reticulum has relatively few bound ribosomes and does a variety of functions including synthesis, storing Ca2+ and detoxification
smooth
a role of the ______ ER is the modification of foreign substances to make them less toxic
smooth
cells that carry out extensive lipid synthesis, such as those in the tests, intestine and brain, have abundant ______ ER
smooth
steroid hormones are synthesized in the ______ ER as well
smooth
the _____ ER has a variety of structures ranging from a network of tubules, to flatted sacs, to higher order tubular arrays
smooth
surrounding the thylakoid is a fluid matrix called the _______, and within this is found the enzymes used to synthesize glucose during photosynthesis
stroma
mitochondria metabolize ______ to generate ATP
sugar
the cell __________ provides the only opportunity for interaction with the environment because all substances enter and exit a cell via this
surface
ratio of _______ to _______ limits size of cell
surface area (r^2) to volume (r^3) -as a cell's size increases, its volume increases much more rapidly than its surface area
the rate of diffusion of cells is affected by (4)
surface area, temperature, concentration gradient and distance
______ is a close relationship between organisms of different species that live together
symbiosis
a eukaryotic cell does not produce brand new mitochondria each time the cell divides, rather _______
the mitochondria itself splits into 2
double membrane structure that surrounds DNA in the nucleus is
the nuclear envelope
one cell, a prokaryote, was engulfed by and became part of another cell, which was the precursor of modern eukaryotes
theory of endosymbiosis
a chloroplast may contain a hundred or more grana and each may contain from a few to several dozen disked shaped structures called ______
thylakoids
__________ are membranous sacs within the inner membrane and ___________ are stacks of these
thylakoids, grana
________ junctions are unique to vertebrates and contain proteins called Claudins because of their ability to occlude or block substances from passing between cells. this form of junction between cells acts as a wall within the tissue, keeping molecules on one side or the other
tight
the membrane surrounding the central vacuole is called the _________ because it contains channels for water that are used to help the cell maintain its tonicity (osmotic balance)
tonoplast
the face where materials exit the golgi body is the ______ face where they are discharged in secretory vesicles
trans
__________ proteins help molecules and ions move across the plasma membrane
transfer
electrons used to visualize the specimens are transmitted through the material, resolving objects only 0.2 nm apart
transmission electron microscopes (TEM)
plant cells have specialized membrane-bounded structures called
vacuoles
both plant and animal cells contain______ which are smaller sacs that store and transport a variety of materials
vesicle
mitochondria are replace in some tissues every _____ days
10
cells were discovered in 1665 by
Robert Hooke
______ can manufacture their own food
chloroplasts
eukarya is a domain of
eukaryotes
the ___________ functions in the collection, packaging and distribution of molecules synthesize at one location and used at another within or even outside of the cell
golgi apparatus
the complicated process of protein synthesis by ribosomes requires ribosomal RNA, along with two other forms of RNA
messenger and transport
eukaryotic cells contain a variety of enzyme bearing membrane enclosed vesicles called
microbodies
most bacterial cells are encased by a strong cell wall composed of
peptidoglycan
surrounding the centrioles in the centrosome is the _______ _______ which contains ring shaped structures composed of tubulin and can nucleate the assembly of microtubules in animal cells
pericentriolar material
an important type of micro body is the _______ which contains enzymes involved in the oxidation of fatty acids
peroxisome
contain enzymes involved in the oxidation of fatty acids
peroxisomes
in addition to breaking down organelles and other structures within cells, lysosomes eliminate other cells that the cell has engulfed by _______
phagocytosis
archaea and bacteria are 2 domains of
prokaryotes
cell's protein synthesis machinery
ribosomes
in both prokaryotes and eukaryotes dan is the molecule that stores genetic information (TRUE OR FALSE)
true
eukaryotic flagellum consist of a circle of nine microtubule pairs surrounding _____ central microtubules
two
ribosomes can be thought of as "________ _________" because they are found in all cell types from all three domains of life
universal organelles
plant cells grow by expanding the _______, rather than by increasing cytoplasmic volume
vacuole
membrane bound structures in plants with various functions depending on the cell types
vacuoles