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Cells and Tissues

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Cells
microscopic cubelike structures; the smallest structure of all living things.
electrolytes
carry an electrical charge.
generalized cell
demonstrates many normal cellular features
nucleus
the control center for the cell
deoxyribonucleic acid
blue print for all of the body
proteins
DNA is instructions for building proteins
nuclear envelope
double membrane barrier
nuclear membrane
same as nuclear envelope; double membrane barrier
nucleoplasm
jellylike fluid enclosed by the nuclear membrane
nucleoli
small, darkstaining, essentially round bodies contained by the nucleus
chromatin
a loose network of bumpy threads
chromosomes
rod like bodies formed from chromatin
plasma membrane
a fragile, transparent barrier that contains everything in the cell
microvilli
tiny fingerlike projections that greatly increase the cells surface area
membrane junctions
vary structurally depending on their roles; membrane junctions
tight junctions
plasma membranes fuse together tightly like a zipper
desmosomes
anchoring junctions that prevent cells subjected to mechanical stress from being pulled apart
gap junctions
mainly to allow communication
connexons
hollow cylinders composed of proteins that span the entire width of the abutting membranes
cytoplasm
the cellular material outside the nucleus and inside the plasma membrane
cytosol
semitransparent fluid that suspends the other elements
organelles
microscopic organs for the cell
inclusions
not functioning units, but instead are chemical substances that may or may not be present, depending on the specific cell type
lysosomes
contain powerful digestive enzymes
peroxisomes
contain powerful oxidase enzymes
mitochondria
the powerhouse of the cell
ribosomes
made of proteins, and where protein synthesis occurs
endoplasmic reticulum
it is a minicirculatory system for the cell
rough endoplasmic reticulum
contains ribosomes, but the smooth one doesn't
golgi apparatus
a stack of flattened membranous sacs associated with swarms of tiny vesicles
free radicals
highly reactive chemicals with unpaired electrons that can scramble the structure of proteins and nucleic acids
cytoskeleton
acts as the cells bones and muscles
intermediate filaments
help form desmosomes
microfilaments
involved in cell motility and changes in the shape of the cell
centrioles
rod shaped bodies that lie at right angles to each other
cilia
projections
flagella
a tail like thing
solution
homogeneous mixture of 2 or more components
solvent
something present in a larger amount in a mixture
solutes
the thing that dissolves in solution
intracellular fluid
a solution containing small amounts of gases
interstitial fluid
the fluid that continuously bathes the exterior of our cells
selective permeability
has to deal with what goes in and comes out of the cell
passive transport process
things are transported without any energy used from the cell
active transport process
things are transported using cellular energy
diffusion
the process by which molecules tend to scatter themselves throughout the available space.
concentration gradient
where the particles are more abundant
simple diffusion
unassisted diffusion of solutes through the plasma membrane
osmosis
diffusion of water through a selectively permeable membrane
facilitated diffusion
provides a means for certain needed substances
filtration
the process by which water and other substances are forced through a membrane by fluid or hydrostatic pressure
pressure gradient
the gradient that actually pushes solute containing fluid from a place of high pressure to a place of low pressure
solute pumping
similar to facilitated diffusion in which both require protein carriers
solute pumps
protein carriers
exocytosis
moves substances out of cells
endocytosis
moves substances into cells
bulk transport
means of moving things into and out of cells
bulk phase endocytosis
the way cells drink
pinocytosis
what the way the cells drink used to be called
cell life cycle
the cycle of changes in a cell
interphase
the cell grows and carries on metabolistic activities
cell division
the point in a cell's life in which it divides
template
a set of instructions for a new nucleotide strand
mitosis
cell division
cytokinesis
the division of cytoplasm in mitosis
prophase
the process of chromatin coiling up in mitosis
chromosomes
the things that make us who we are
chromatid
the 2 strands that make up chromosomes
centromere
small button like body
mitotic spindle
centrioles separate from each other and begin to move toward opposite sides of the cell, directing the assembly
cleavage furrow
appears over the midline of the spindle, and it eventually squeezes or pinches the original cytoplasmic mass into 2 parts
gene
a DNA segment that carries the info for building one protein or polypeptide
transfer RNA molecules
small cloverleaf-shaped molecules
ribosomal RNA
helps form ribosomes, where proteins are built
messenger RNA molecules
long, single nucleotide strands that resemble half of a DNA molecule and carry the message containing instructions for protein synthesis from the DNA gene in the nucleus to the ribosomes in the cytoplasm
transcription
involves the transfer of information from DNA base sequence into the complementary base sequence of mRNA
triplet
each three base sequence specifying a particular amino acid on the DNA gene
codons
the corresponding three base sequences on mRNA
translation phase
the language of nucleic acids is translated into the language of proteins
anticodon
special three base sequence
epithelium
the lining or covering and glandular tissue of the body
apical surface
exposed to the bodys exterior or to the cavityof an internal organ
basement membrane
a structureless material secreted by the cells
simple epithelium
one layer of cells
stratified epithelium
more that one cell layer
serous membranes
slick membranes that line the ventral body cavity and cover the organs in that cavity
goblet cells
produce a lubricating mucus, are often seen in this type of epithelium
mucous membranes
epithelial membranes that line the body cavities open to the body exterior
pseudostratified columnar eptithelium
rest on a basement membrane
stratified squamous epithelium
the most common stratified epithelium in the body
stradtified cubodical epithelium
usually has just 2 cell layers with the surface cells being in the cubodial shape.
transitional epithelium
highly modified, stratified squamous epithelium that forms the lining of only a few organs
exocrine glands
retain their ducts, and their secretions empty through the ducts to the epithelial surface
connedtive tissues
connects body parts
extracellular matrix
a nonliving substance found outside of cells
hyaline cartilage
has abundant collagen fibers hidden by a rubbery matrix with a glossy, blue white appearance
fibrocartilage
forms the cushionlike disks between the vertebrae of the spinal column
elastic cartilage
found where a structure with elasticity is desired
dense connective tissue
has collagen fibers as its main matrix element
tendons
attach muscles to bones
ligaments
connect bones to bones
areolar tissue
the most widely distributed connective tissue varieties in the body
edema
a puffy condition
adipose tissue
fat tissue below the dermis
reticular connective tissue
a delacate nework of interwoven reticular fibers associated with reticular cells
stroma
bed or mattress
blood
vascular tissue
muscle tissue
tissue that contracts in order to make movement
striations
stripes
intercalated disks
the junctions where branching cells fit tightly together
supporting cells
insulate, and support, and protect the delicate neurons
regeneration
the replacement of destroyed tissue by the same kind of cells
fibrosis
involves repair by dense connective tissue, that is, by the formation of scar tissue