Bio Exam 2
what is cell theory?
the idea that all living things are composed of cells
what is rate of diffusion?
surface area, temperature, concentration gradient, and distance
the surface area to volume ratio of a cell...
accoubt for their size limits
name two types of microscopes.
light and electron
define light microscope.
microscope that uses beams of light through multiple lenses to magnify object
define electron microscope.
microscope that forms an image by focusing beams of electrons onto a specimen
list the basic structural similarities of all cells.
nucleoid where DNA is located in the nucleus; cytoplasm with organelles and cytosol; ribosomoes that use protein synthesis; plasma membrane that has the phospholipid bilayer
define prokaryotic cell.
a cell that lacks a membrane enclosed nucleus and organelles
name the two domains of prokaryotic cells
bacterial and archaea
bacterial cell walls contain...
peptidoglycan
what is the function of a cell wall?
protect, maintain shape, and prevent excessive uptake or loss of water
archaea lacks...
peptidoglycan
define eukaryotic cells
possessa membrane bound nucleus
what is the function of a eukaryotic cell?
support and maintain cellular structure
animal and plants have the same...
DNA and organelles
what cells have s plasma membrane?
animal and plant cells
plant cells do not present...
eukaryotic cells
plant cells have their cellular wall...
outside
what cell has chloroplasts and speciallized vacuoles internally?
plant cells
define nucleus
repository of genetic information
define nucleolus
region where ribosomal rna takes place
how many nucleuses does eukaryotic cells have?
one
define nuclear envelope
two phospholipid bilayers
define nuclear pores
control movement between nucleus and cytoplasm
what is divided into multiple linear chromosomes in eukaryotic cells?
dna
what is chromosomes plus protein?
chromatin
define ribosomes
site of protein synthesis
protein synthesis requires...
both messenger and transfer rna
define endomembrane system
series of membranes across the cytoplasm
what is the function of endomembrane system
divides cell into compartments
what is the difference between eukaryotes and prokaryotes!
endomembrane system
define endoplasmic reticulum
a cellular structure that forms a maze of passages so proteins can be moved about the cell
define rough er
attachment of ribosomes
what is the function of rough er?
synthesis of proteins are secreted and sent to lysosomes and plasma
define smooth er
makes lipids
what is the function of smooth er?
synthesis, stores ca^2, detoxification
the ratio of smooth er and rough er depends on...
cells function
define golgi apparatus
flattened stack of interconnected membranes
what is the function of golgi apparatus?
modifies, packages, stores, and transports lipids
define lysosomes
organelled containing digestive enzymes
lysosomes come from...
golgi apparatus
lysosomes fuse with the target to initiate...
breakfown
define microbodies
variety of of enzyme bearing, membrane enclosed vesicles
define microbodies peroxisomes
contains enzymes to convert hydrogen peroxide to water and oxygen
define vacuoles
membrane bound structure found in plants
vacuole functions depend on...
cell type
name types of vacuoles
central, storage, contractile
central vacuoles are in...
plant cells
storage vacuoles are in...
plants
contractile vacuoles are in...
fubgi
define mitochondria
organelle found in cells of plants that capture energy from sun and turn it into chemical energy
chloroplasts contain...
chlorophyll for photosynthesis
define thylakoids
membranous sacs within the inner membrane
define grana
stacks of thykaloid
chloroplasts have their own...
DNA
define endosymbiotic theory
proposes that eukaryotic organelles evolved by symbiosis between two free living cells
mitochondria and chloroplasts have similarities to...
prokaryotic cells
define cytoskeleton
network of protein fibers found in all eukaryotic cells
what is the function of a cytoskeleton?
supports the shape and keeps organelles where they are supposed to be
what is constantly forming and disassembling?
dynamic systems
defibe microfilaments
two protein chains loosly intertwined
define microtubules
faciliate movement of cell
define intermediate filaments
between microfilaments and microtubules
define centrosomes
refion surroundjng centrioles in all aminal cells
define glycolipids
tissue specific cell surface markers
define mhc proteins
recognition of self and nonself cells
list cell connections
adhesive junctions that attaches cytoskeletons to ecm; tight junctions that connect plasma membranes to adjacent cells; communicating functions where chemical and electrical signals pass directly from one cell to another
list the four components of cellular membranes
phospholipid bilayer, transmembrane proteins, interior protein network, and cell surface markrrs
what is the structure of phospholipids?
glycerol, two fatty acids attached to glycerol, and phosohate group attached to glycerol
list functions of membrane proteins
transporters, enzymes, cell surface markers, cell to cell adhesion proteins, attachments to cytoskeleton
define passive transport
movement of molecules through membrane
define diffusion
movement of molecules from high to low concentration
define gated channels
open or close in response to stimuli
list functions of carrier proteins
transport ions by movement of diffusion
define saturation
rate of transport limited to number of transporters
define osmosis
net diffusion of water across membrane for both high and low concentration
name two bulk transports
endocytosis and exocytosis
define endocytosis
movement of substances into cell
define exocytosis
movement of substances out of a cell