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