56 terms

BIOL 116 chapter 8

cell-cell interactions
fibre composites
consists of a cross-linked network of long filaments embedded in a stiff surrounding material
fibre composites
rugged structures composed of strong rods and filaments
primary cell wall
fibre composite secreted by newly formed cells. consists of cellulose
carbohydrates that have hydrophillic polysaccharides. synthesized in Rough ER and golgi apparatus
carbohydrate that composes the cell wall
turgor pressure
force that exerted when incoming water inflates the plasma membrane
secondary cell wall
layer secreted inside the primary cell wall when plants mature
substance that supports a secondary cell wall. is tough and rigid
extracellular matrix
fibre composite secreted by animal cells. consists of protein fibres and is synthesized by the Rough ER and Golgi apparatus
structural support
the main function of the extracellular matrix
protein that makes up the extracellular matrix
actin filaments in the cytoskeleton are connected to this transmembrane.
proteins that integrins bind to. they link cytoskeleton and extracellular matrix
physical connections between cells
consist of groups similar to cells that perform a similar function
integrated structures that are formed when several tissues are combined
cell-cell attachments
distinctive layer of material that joins plant cells together
cell-cell attachments
primary cell walls of adjacent cells attach to a central layer designated in the middle lamella
glues cell walls together
tissues that form an external and internal surfaces
form layers that separate organs and other structures
tight junctions
cell-cell attachment composed of specialized proteins in the plasma membrane
tight junctions
line up and bind to one another to form a watertight seal
cell-cell connection found in animal cells
selective adhesion
cells of different types adhere to the same tissue type
protein that binds specifically to a section of another protein
molecules in desmosomes
each major type of cell has a different type of __ in its plasma membrane
in plants: connections between cytoplasm of adjacent cells
gaps in cell walls where plasma membrane and cytoplasm of two cells are continuous. smooth er runs through these holes
gap junctions
adjacent animal cells are connected by these structures
gap junctions
create channels between cells. allow water, ions and small molecules to move in between cells
info-carrying molecule that is secreted from a cell
if a __ is lipid soluble, it can diffuse across a membrane
presene of an appropriate ___ dictates which cells will be able to resond to a particular hormone
long-distance signalling
coordinates the activities of cells throughout a multicellular organism
signal receptors
proteins that change overall shape after binding to a signalling molecule
beta blockers
signal receptors can be blocked by these
signal transduction
is triggered by a hormone's arrival at the cell surface
signal transduction
conversion of the signal from one to another
signal amplification
occurs when a hormone arrives at the cell surface and transmits a message. occurs inside the cell at the plasma membrane.
g proteins
peripheral membrane proteins inside the cell
g proteins
bind to GTP and GDP
g proteins
activated by a cell receptor changing shape in response to a hormone binding
protein kinases
activated by several second messengers. activate or inactivate other proteins by adding a P group to them
receptor tyrosine kinases
enzyme linked receptors. when a hormone binds to one of these, the protein responds by forming a dimer
once it is ___, a receptor tyrosine kinases (RTK) becomes an active enzyme
receptor tyrosine kinases
peripheral membrane protein that functions like a G protein
once activated, it triggers phosphorylation of an intracellular protein
proteins form a bridge to this protein. then it exchanges its GDP for a GTP
phosphorylation cascade
each enzyme in this cascade catalyzes phosphorylation
addition of a phosphate group to a molecule.
receptor tyrosine kinase
once activated, it can trigger the activation of thousands of proteins
signal transduction systems
trigger a rapid response and can be shut down quickly
provide the physical basis for selective adhesion and are a critical component of the desmosomes