list the four concepts of cell theory

1.basic structural and functional unit 2. organisms activity is based on cells activity 3. biochemical chemical activty determines & is determined by subcellular structure 4. continuity of life is based on cell reproduction

describe three diffferent cell shapes

cubelike, disk shaped, tilelike, spherical, branching, cylindical

name the trhee MAJOR parts of any cell

plasma membrane, cytoplasm, nucleus

define generalized or composite cell

model that describes a cell in terms of common features/ functions that all cells share

does non polar mean hydrophobic or hydrophilic

hydrophobic

what is the structural significance of microvilli

to increase the surface area of the palsma membrane

what type of cell functions does the presence of microvilli typicalls indicate

found on cells involved in secretion and/or absorption

what protien acts as a microvilli stiffener

actin

name two factors in addition to special membrane junctions that help hold cells together

the gylcocalyx and tongue in groove folding of adjacent plasma membranes

which cell junction forms an impermiable barrier

tight junction

which cell junction is buttonlike adhesion

desmosome

which junction has linker protiens spanning the intercellular space

desmosome

which cell junction allows direct passage from one cells cytoplasm to the next

gap junction

what name is given to the transmembrane proteins that allow this direct passage

connexons

engulfment process that require ATP

exocytosis, phagocytosis, receptor-mediated endocytosis, solute pumping

driven by molecular energy

diffusion - simple , diffusion -osmosis

moves down (with) a concentration gradient; requites a carrier

solute pumping

moves up (against) a concentration gradient; requires a carrier

solute pumping

uses a clathrin- coated vesicle (pit)

phagocytosis, pniocytosis, receptor mediated endocytosis

typically involves coupled systems; that is ,symports or antiports

slolute pumping

examples of vesicular transport

exocytosis, phagocytosis,pinocytosis, receptor-mediated endocytosis

a means of bringing fairly large particles into the cell

phagocytosis

used to eject wastes and to seperate cell products

exocytosis

plasma membrane

a) location- external boundry of the cell b) function- confines cell contents, regulates entry and exit of materials

lysosome

a) location- scattered in cytoplasm b) function- digests ingested materials and worn out organelles

mitochondria

a) location - scattered throughout the cell b) function- controls release of energy from foods forms ATP

microvilli

a) location- projections of the plasma membrane b) function - increase the membrane surface area

golgi apparatus

a) location - near the nucleus {in the cytoplasm} b) function- packages protiens to be exported from the cell; packages lysosomal enzymes

centrioles

a) location - two rod shaped bodies near the nucleus b) spin the miotic spindle

smooth ER

a) location- in the cytoplasm b) function- site of steroid synthesis and lipid metabolism

rough ER

a) location- in the cytoplasm b) function- transports proteins (made on its ribosomes) to other site in the cell; site of membrane lipid synthesis

ribosomes

a) location- attached to Er membranes os scattered in the cytoplasm b) function- sythesize proteins

cilia

a) location -extensions of cell to exterior b) function- act collectively to move substances scross cell surface in one direction

microtubules

a) location- internal structure of centrioles; part of the cytoskeleton b) function importnat in cell shape, suspend organelles

peroxisomes

a) location - throughout cytoplasm b) function detoxify alcohol and free radicals accumulating from normal metabolism

microfilaments

a) location - throughout cytoplasm; part of cytoskeleton b) function -contractile protein (actin) moves cell or cell parts, core of microvilli

intermediate filaments

a) location - part of cytoskeleton b) function act as internal "guy wires" help form desmosomes

inclusions

a) location - dispersed in the cytoplasm b) function - provide nutriens, represent cell waste products,etc.

prophase

a. chromatin thickens to form chromosomes b. spindle apparatus form c. nuclear membrane dis appears d. nucleolus disappears

metaphase

chromosomes line up in the middle of the cell

ananphase

chromosomes are pulled to opposite poles by the spindle fiberse

when does cytokinesis begin

during anaphase

telophase

a. chromatin thins b. spindle apparatus disapear c. nuclear membrane appearrs d. nucleolus appears

osmosis

movement of water from high to low concentration

tonicity

ability of a solution to cause a cell to shrink of swell

isotonic

a solution with the same solute concentration as that of the cytosol --- stays the same

hypertonic

a solution having greater solute concentration than that of the cytosol --- cell shrivels

hypotonic

a solution having lesser solute concentration than that of the cytosol --- cell expands and bursts

phagocytosis

pseudopods engulf solids and bring them into cells interior

pniocytosis

the cell gulps drops of extracellular fluid containing solutes into tiny vessicle

exocytosis

the cell getting rid of waste -hormone secretion, neurotransmitter releases, mucus secretion, ejection of wastes

G1

cell growth - reaady for DNA replication

S

DNA replication

G2

cell growth - ready for motosis , The final period of interphase during which the cell prepares for mitosis.

GO phase

a phase of the cell cycle in which the cell is not dividing and its DNA is not replicating

mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

leading strand

the new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' --> 3' direction

lagging strand

A discontinuously synthesized DNA strand that elongates in a direction away from the replication fork.

stages of mitosis

prophase, metaphase, anaphase, telophase

cleavage furrow

The first sign of cleavage in an animal cell; a shallow groove in the cell surface near the old metaphase plate.

miosis

(genetics) cell division that produces reproductive cells in sexually reproducing organisms