Plant Cell Structure Part 2 Flashcards
make and store needed compounds
plastids
started as a bacteria that were absorbed into plant cells
plastids and mitochondria
most important of all plastids, light -> sugar & oxygen
chloroplasts
organelles in animals do not give the cell shape
vacuole
plant cells push water into these organelles
central vacuole
structural and functional units of living structures
cell
scientist that reported thin slices of cork and other plant materials contained minute partitions separating cavities that are eventually named cells
Robert Hooke
discovered the microscope and “free cells” with nucleus
Anton van Leeuwenhoek
discovered the cell substance (protoplasm)
Dujardin
stated that many living bodies must have parts of cellular tissue or formed by such tissue
Jean Baptiste de Lamarck
described the nucleus as the central feature in plant cells, discovered the movement of microscopic particles
Robert Brown
stated that cells were the unit of structure in animals
Theodor Schwann
concluded that cells come only from other cells
Rudolf Virchow
stated that cells ensure continuity between one generation through mitosis
Alexander Flemming
who proposed the cell theory
Rudolf Virchow and Theodor Schwann
basic tenets of cell theory
all living organisms are made up of cell
the cell is the basic unit of structure of all living organisms
all cells come from pre-existing cells
how small are Rickettsia
0.3 to 0.5 micrometers
how small are prokaryotes (bacterial groups)
1 to 10 micrometers
example of cells that can be seen
“yolks” of eggs in most vertebrates
why are most of the cells are small
ratio of the volume of the cell’s nucleus to the volume of cytoplasm must not be so small for the nucleus to control the cytoplasm
as a roughly spherical cell becomes larger, the innermost regions become farther away from the membrane which makes diffusion ___
difficult
difference of prokaryotes and eukaryotes
prokaryotes have cell walls, only plant cells in eukaryotes have cell walls
prokaryotes does not have nucleus, nuclear membrane, nucleolus
prokaryotes only have ribosomes and cilia and flagella
prokaryotes have single, circular, w/o associated proteins in chromosomes
prokaryotes have RNA and DNA as its genetic material
why does cell volume work to limit cell size
as the cell enlargens, its volume increases more rapidly than its surface area does. Larger cell has a greater need for exchange of nutrients and wastes with the environment.
what cells can get large due to their elongated shape
muscle cells and neurons
three structural parts of an animal cell
plasma membrane
cytosol
nucleus
gatekeeper of the cell, outer limiting membrane in animal cells
plasma membrane
thick-semi fluid portion of the cytoplasm
cytosol
other term for cytosol
intracellular fluid
large, double membrane organelle that contains the chromosomal DNA of a eukaryotic cell
nucleus
highly organized stuctures with characteristic shapes that are highly specialized for specific cellular activities
organelles
temporary structures that contain secretions and storage products of the cell
inclusions
functions of cell membrane
-acts as separation between the internal components of the cell from the extracellular environment
-allows passage of selected molecules, regulating the exchange of substances between the cell’s protoplasm
-communicates with other cells
described the molecular arrangement of the plasma membrane and other membranes in living organisms
fluid mosaic model
pattern of many small pieces fitted together
mosaic
proteins are flowing like what in a sea of lipids
icebergs
percent of phospholipids in the cell membrane
75 percent
form the bilayer, the arrangement occurs because it is ampipathic
phospholipid bilayer
what part faces the watery cytosol and ECF
phosphate head
amphipathic occurring only on the membrane layer facing the ECF
glycolipids
what percent is glycolipid in the cell membrane
5 percent
function of glycolipids
adhesion among cells and tissues
cell-to-cel recognition and communicaton
exposed on brain and nerve cell membranes as antigens
gangliosides
serve as antigens on surfaces of RBCs for blood group interaction
glycosphingolipids
located among the phospholipids in both sides of the bilayer, strengthen the membrane but decrease its flexibility
cholesterol
how many percent is cholesterol in the membrane
20 percent
two types of membrane proteins in plasma membrane
integral and peripheral
extend across the phospholipid bilayer among the fatty acid tails, mostly glycoproteins
intrinsic/integral proteins
loosely attached to the inner and outer surfaces of the membrane and are easily separated from it
extrinsic/peripheral proteins
determine what functions a cell can perform
membrane proteins and glycoproteins
function of proteins
channel
cell identity markers
cytoskeleton anchor
transporter
enzymes
receptor
function of proteins that allows passage of specific molecules (K+ Cl-) to move through the pore
channel
function of proteins that carries specific substance across
transporter
function of proteins that catalyzes different reactions
enzymes
example of a transporter protein
amino acids
example of a enyzme protein
adenylyl cyclase
converts ATP to cAMP
adenylyl cyclase
function of protein that distinguishes cell from other cells
cell identity markers
example of cell identity marker protein
glycosphingolipids
function of proteins that recognizes specific molecules (e.g. hormones) and alter cell’s function in some ways
receptors
function of protein that attaches filaments and tubules inside the cell to the cell membrane to stabilize the structure and shape of the cells
cytoskeleton anchor
usually spherical or oval organelle and is the largest structure in the cell
nucleus
contains the hereditary units of the cell which control cellular structure and direct many cellular activities
nucleus
example of body cells that do not have a nucleus
mature RBCs
what fibers contain several nuclei
skeletal muscle fibers
separates the nucleus from the cytoplasm
nuclear membrane
allow most ions and water-soluble molecules to shuttle between nucleus and cytoplasm
nuclear pore (water-filled)
about ten times large in diameter than channels in the plasma membrane and thus permit larger passage of large molecules such as RNA and various proteins
nuclear pore
nucleus unside a nucleus
nucleoli
aggregation of proteins, DNA, and RNA that are not bounded by a membrane
nucleoli
disperse and disappear during cell division and reorganize once new cells are formed
nucleoli
sites of assembly of ribosomes which can contain rRNA
nucleoli
type of RNA that plays a key role in protein synthesis
rRNA
loosely packed DNA and associated proteins
chromatin
process where DNA and certain proteins condense and coil into rod-shaped bodies
cell division
tightly packed DNA during cell division
chromosomes
through an electron microscope, chromatin appears like
beads on a string
each bead consists of double-stranded DNA wrapped twice around a core of 8 proteins
nucleosome
8 proteins where the nucleosome is wrapped twice around in
histones
strings between heads, which folds an adjacent nucleosomes together
linker DNA
histones that promote the folding of nucleosome into a large diameter structure
chromatin fiber
before cell division, DNA duplicates and chromatin strands subsequently shorten and turn into this
chromatids
pair of chromatids make a
chromosome
specialized structures that have characteristic appearances and specific roles in growth, maintenance, repair, and control
organelles
contains numerous ER and golgi complex to meet its function of production and secretion of bile
liver cell
do not have mitochondria that would consume oxygen
mature red blood cell
universally present within animal cells except in mature red blood cells
mitochondria
capable of self-replication i.e. they have to divide to increase in number in response to cellular need for ATP and cell division
mitochondria
mitochondrion consists of two membran es:
outer mitochondrial and inner mitochondrial membrane
which membrane of the mitochondria is smooth
outer mitochondrial membrane
which membrane of the mitochondria is arrange in a series of folds
inner mitochondrial membrane
series of folds in mitochondria
cristae
central cavity of a mitochondrion that is enclosed by the inner membrane and cristae
matrix
tiny spheres that contain rRNA and several ribosomal proteins
ribosomes
two types of ribosomes
free and attached ribosomes
manufacture proteins for domestic use
free ribosomes
manufacture proteins for export use
attached ribosomes
example of free proteins
membrane proteins and enzymes (catalase)
form perixosomes
catalase
example of attached proteins
secretory proteins (enzymes and hormones)
system of membrane-enclosed channels of varying shapes called cistern/cisternae
endoplasmic reticulum
function of rough endoplasmic reticulum
protein synthesis
glycosylation
addition of carbohydrate groups to glycoproteins
glycosylation
function of smooth endoplasmic reticulum
lipid synthesis
drug detoxification
carbohydrate metabolism
calcium storage
addition of OH groups increasing solubility of hydrophobic drugs in water so they can easily be exerted from the body
hydroxylation
breakdown of glycogen by glucose-6-phosphatase
carbohydrate metabolism
stores and releases calcium during relaxation and contraction respectively
sacroplasmic reticulum
what do muscle cells do to calcium when it relaxes
reduces
what do muscle cells do to calcium when it contracts
stores
membrane-bound enzyme that breaks down glycogen
glucose-6-phosphatase
difference between cristae and cisternae
cristae (mitochondria), cisternae (endoplasmic reticulum, golgi)
cristae (contains proteins, including ATP and cytochrome), cisternae (enzymes)
located near the nucleus, consists of 4-6 flattened sacs called cisternae stacked upon each other like a pile of plates with expanded bulges in the end
golgi complex
shuttle protein and lipid products among the cisterns for further processing and modification
vesicles
route of proteins to be exported
ribosomes -> RER -> transport vesicles -> golgi complex -> secretory vesicles -> released via exocytosis
membrane-enclosed vesicles that form in the Golgi complex
lysosomes
function of lysosomes
intracellular digestion
autophagy
autolysis
extracellular digestion
function of lysosomes where enzymes digest bacteria and other substances
intracellular digestion
examples of intracellular digestion
phagocytosis
pinocytosis
receptor-mediated endocytosis
vesicles that arise during phagocytosis, pinocytosis, and endocytosis
phagosomes (phagocytic vesicles)
pinocytic vesicles
endosomes
function of lysosomes where the cell’s own structure are recycled
autophagy
function of lysosomes wherein it acts as “suicide bags” during apoptosis
autolysis
cells themselves die in order to go about normal development
apoptosis
function of lysosomes where lysosomal enzymes released at the sites of injury help digest cellular debris, which prepares the injured area for effective repair
extracellular digestion
similar in structure to lysosomes and is capable of self-replication like mitochondria
peroxisomes
found in numerous kidney and liver cells
peroxisomes
functions of peroxisomes
hydrogen peroxide metabolism
detoxification of harmful compounds
oxidation of fatty acids
generate hydrogen peroxide
oxidase
degrades hydrogen peroxide
catalase
detoxifies methanol, ethanol, formic acid, formaldehyde, nitrites, phenols
catalase
shorten fatty acids in preparation for subsequent metabolism in mitochondrion to produce acetyl coenzyme A
peroxisomes
complex internal network of filamentous proteins in cytoplasm
cytoskeleton
cellular shape and has a capability to carry out coordinated movements
cytoskeleton
responsible for the movement of whole cells such as phagocytes and movement of organelles and chemicals within the cells
cytoskeleton
three main types of protein filaments
microtubules
intermediate filaments
microfilaments
hollow cylindrical structures about 25nm in diameter
microtubules
protein that assembles microtubules
tubulin
functions of microtubules
support and shape cells with microfilaments
acts as “conveyor belts”, “road”, or “tracts”
assist in movement of pseudopods
form structure of flagella, cilia and centrioless
composed of rope-like protein strands which are 8-12nm in diameter
intermediate filaments
exceptionally strong and tough and are resistance to tensile forces and are relatively insoluble
intermediate filaments
functions of intermediate filaments
mechanical stability due to plectin crossbridges
structural reinforcement inside cells
holds organelles in place
associate closely with microtubules to give shape to the cell
bind intermediate filaments together, also binds microtubules and microfilaments
plectin
twisted double strands, each consisting of a string of protein (actin) subunits about 8nm in diameter
microfilaments
function of microfilaments
plays a key role in contractility and motility
slide past one another to produce contraction (shortening) of muscle fiber
muscle tissue
what are the thin filaments and thick filaments in muscle tissues
actin filaments (thin), myosin filaments (thick)
actin in non-muscle cells provide support and shape to assist in:
cell movement (phagocytic)
movement within cell (phagocytosis and phinocytosis)
latin for eyelash
cilia
latin for whip
flagella
slender extensions of the plasma membrane
cilia and flagella
how many fused pairs of microtubules does cilia and flagella have
9 fused pair
how many unfused pairs of microtubules does cilia and flagella have
2 unfused pair
difference between cilia and flagella in length
50-75 micrometer long (flagella)
10-25 micrometer long (cilia)
difference between cilia and flagella in number
few (flagella)
numerous (cilia)
difference between cilia and flagella in motion
undulate and continuous bending (flagella)
stiff rowing during the Powerstroke (cilia)
without distinct power and return strokes (flagella)
flexible return stroke that brings it to original position (cilia)
difference between cilia and flagella in direction of force
perpendicular to the plasma membrane (flagella)
parallel to the plasma membrane (cilia)
examples of ciliated protozoans
paramecium
dinidium
euplotes
example of flagellated protozoans
euglena
trypansoma
dinoflagellates
example of flagellated cells
sperm cells
cells that propel substances along their surfaces
ciliated cells
examples of ciliated cells
gills of oysters
oviducts of females
respiratory tracts of most land vertebrates
dense area of cytoplasmic material near the nucleus
centrosome
pair of cylindrical structures found within the centrosome
centrioles
each centriole is composed of:
nine clusters of three microtubules arranged in a circular pattern
function of centrioles
centers for organizing microtubules in nondividing cell
organizes the mitotic spindle during cell division
fluid-filled sacs surrounded by single membrane
vacuoles
temporary features of the cell, formed during phagocytosis
food vacuole
freshwater organisms have this in order to withstand a hypotonic environment
contractile vacuoles