plasma membrane
outer layer of cell
cytoskeleton
internal protein network for support/transport
cytosol
jelly like fluid in the cell
cytoplasm
the space between the nucleus and plasma membrane
organelles
perform cellular functions
endomembrane system
organelles connected by membranes or exchange membrane bound transport vesicles
organelles job
protein production pathway
nucelus
contain DNA DNA is instructions to build proteins surrounded by nuclear envelope "double membrane"- contains pores
nuclear envelope
membrane barrier that separates the nucleus from the cytoplasm
mRNA
messenger RNA "photocopy" of DNA instructions
nucleolus job
produces ribosome subunits
ribosome job
protein synthesis
if ribosome is free in cytoplasm then
the proteins are used in the cytosol
if ribosomes is bound to the rough ER then
the proteins are exported from the cell
rough endoplasmic reticulum
membrane network lined with ribosomes
rough ER main functions
modifies proteins eliminates faulty proteins produce membrane
ER lumen
continuous space within nuclear envelope
smooth endoplasmic reticulum
enzymes synthesize lipids - fatty acids, phospholipids, steroids, detoxify drugs metabolize carbs store Ca2+ = muscle contractions
golgi complex
processes and distributes product from the ER produces polysaccarides layers of flat membrane sacs vessicles to and from the golgi - more golgi = more secretion
lysosomes
membrane bound organelle that contains digestive enzymes
autophagy
digesting dysfunctional organelles
mitochondria
powerhouse of the cell produces ATP - adenosine triphosphate generates body heat
chloroplasts
captures suns energy
endosymbiosis meaning
inside-together-life
endosymbiosis in mitochondria and chloroplasts
both have 2 membranes both have DNA - circular shape both have their own ribosomes
microfillaments
cell shape, movement, muscle contraction
intermediate fillaments
cell shape, organelle anchoring
microtubules
chromosome and organelle movement flagella and cilia
plants vs animals
plants lack lysosomes plants have -cell walls -central vacuole -chloroplasts
cell wall
provides structure and support
central vacuole
stores h2o, pigments, and waste
plant cell junctions
plasmodesmata channels connecting plant cells helps with diffusion of molecules in cytoplasm
animal cell junctions
gap junctions similar to plasmodemata found in heart and animal embryonic stage
tight conjunctions
leakproof sheet line digestive tract
desmosomes
anchoring junctions strong connection in stressed tissue skin and heart muscle
cell membranes
boundary between cell interior and membrane enables. internal regulation- char. of life membranes are both flexible and stable
all cells have external plasma membrane
but eukaryotes have internal as well
membranes have a
phospholipid bilayer
hydrophillic head
react well with h2o in cell
hydrophobic tail
keep stability in the cell
cholesterol
helps keep membranes more fluid @ cool temps less fluid @ warm temps
membranes are
selectively permeable
selective permeability is
when some substances can cross more easily than others
hydrophobic molec pass through
non-polar membranes
hydrophillic molec pass through
polar membranes
fluid mosaic model
integral membrane proteins
pass into or through hydrophobic region of the membrane
peripheral membrane proteins
attach to the outside of the membrane
membrane protein functions
transport enzymes, cell communication, physical attachment
glycoproteins made of
carb + protein
glycolipid and glycoprotein functions
used in cell identification immunity (self vs non self) embryonic cell sorting
passive transport
not requiring cellular energy
diffusion
passive transport movement from high concentration to low concentration all molec are in constant mostion each molec moves independently from other molec
factors that influence diffusion rate
size of molecule/ membrane the concentration gradient
larger difference in gradient = faster temperature
warmer = faster elec. or pressure gradients
facilitated diffusion
passive transport movement aided by membrane proteins with a channel or carrier
what needs facilitated diffusion
larger molec, polar molec, charged molec
aquaporin
facilitated protein for H2O needed bc water is polar
facilitated proteins have
specific shape for each substance ex enzymes
osmosis
movement of free H2O molec from low solute concentration to high across a semi permeable membrane
isotonic
same concentration on each side no net movement on each side of cell but flow in and out
hypotonic
lower concentration
hypertonic
higher concentration
cells ____ to maintain balance
osmoregulate
animal- lysed
exploded hypotonic
animal- plasmolysed
shrivled hypertonic
plant- flacid
limp hypertonic
plant- turgid
firm hypotonic ideal for plant doesnt explode due to cell wall
____ is ideal for animal cell
isotonic
active transport
cell expends energy for transport up/ against concentration gradient driven by ATP Na+ and K+ pump inside of cell has slight negative charge
cotransport
active transport transport of diff solutes through common protein
exocytosis
exit cell
endocytosis
enter cell
endocytosis and exocytosis functions
fuse with plasma membrane to transport larger molec
phagocytosis
cell eating
pinocytosis
cell drinking
receptor-mediated endocytosis
is a process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane
ligand
molec that binds to the receptor
size of plasma membrane
8nm
DNA
deoxyribonucleic acid
genome
complete set of an organisms genetic information
gene
a segment of DNA that is the coding for polypeptides sequence of amino acids proteins > 1 polypeptide
humans have ___ genes
25,000
there is a ____ copy of genes in almost every cell
full copy
what is DNA's monomer
nucleotides
DNA structure
5 carbon sugar phosphate group nitrogenous base = rungs
sugar phosphate backbone held with H bonds
DNA has a _____ shape
double helix
Purines
adenine and guanine 2 ring structure
pyramidines
cytosine, thymine, uracil in RNA 1 ring structure
A pairs with
T
G pairs with
C/U
differences between DNA and RNA
DNA
double strand
deoxyribose = H, no oxygen
thymine RNA
single strand
ribose = OH
uracil
deoxyribose
5 carbon sugar 1' 2' 3' 4' 5' 1' to nitrogenous base 5' to phosphate group 3' to next nucleotide phosphate
there are ____ bonds within a nucleotide
covalent
there are ____ bonds between nitrogenous bases
hydrogen
what is semiconservative replication
when the parent strand is conserved and acts as a template for the daughter strand
how many origins of replication do prokaryotes have
one
what shape are prokaryotes DNA
circular
how many origins of replication are there for eukaryotes
multiple
what shape is a eukaryotes DNA
linear
helicase function
unwinds DNA