CELL Flashcards
2 types of cells in the body
sex cells and somatic cells
the cytoplasm consists of
cytosol + organelles
4 major functions of the PM
- physical barrier
- regulates exchange of material with the environment
- shows sensitivity to respond to changes in the ECF
- provides cell to cell communication, adhesion, and structural support
4 components of PM
- phospholipids
- proteins
- glycolipids
- sterols
glycoproteins and glycolipids form the
GLYCOCALYX COATING
function of glycocalyx
protection
helps cells survive in stressful environments
are glycolipids and gllycoproteins on the inner or outer layer
outer
what type of protein can be channels
integral proteins
peripheral proteins can be on the inside or outer layer T or F
T
glycolipids are associated only with the _____ and many serve as ___
outer layer
receptors
what stabilizes the cell membrane structure
sterols
membrane allows some material to pass through while inhibiting other material from crossing
selectively permeable
nothing passes
impermeable
are endocytosis and exocytosis passie or active
active
3 forms of passive transport
diffusion
osmosis
facilitated diffusion
osmolarity
total concentration of solute particles in solution
most diffusion of water occurs through
aquaporins
a hyperosmotic solution has
high osmolarity
a hypotonic solution ___ water relative to the cell
loses
solutes are passively transported across a PM by a carrier protein
facilitated diffusion
the cytoskeleton consists of
MT and MF
microvilli contain
microfilaments
what increases the SA/V ratio of a cell
microvilli
what are centrosomes made of
2 centriolles = 9 MT triplets
cilia function
move cell
cilia made of
MT doublets in a 9+2 array
ribosomes are
RNA + protein
what is a network of channels through the cytoplasm
ER
what removes damaged organelles or pathogens
lysosomes
what catabolizes fats and neutralizes toxic compounds
peroxisomes
what synthesizes proteins
ribosomes
osmosis
water molecules moving down a concentration gradient
can facilitated diffusion be unidirectional
yes, but can also be bidirectional depending on conc gradient
what facilitates transport of glucose
GLUT4
active transport uses
exchange pumps
pinocytosis
small molecules + ECF
phagocytosis
solid paticles
phagosomes fuse with ___ to form ____
lysosome
phagolysosome
what removes waste products from cell and recycles membrane components to PM
exocytosis
polar molecules require ___ or __ to cross membrane
ion channels or mediated transport
molecules bind to specific receptors on the cell membrane
receptor mediated endocytosis
exocytosis requires ATP and ___ __ for movement
calcium ions
what absorb material from ECF
microvilli
posttranscriptional processing of pre-mRNA
splicing to remove introns
processed mRNA is selectively transported through ____ to go into the cytosol
nuclear pores
nuclear pores allow mRNA out and ___ ___ in
transcription factors
what catalyzes the formation of peptide bonds
peptidyl transferase
translation of ___ results in binding to signal recognition protein which binds to receptor protein on rough ER
leader sequence (signal sequence)
if there is no leader sequence, the protein will remain in the
cytosol
detoxifies + metabolism functions is the ____ ER
smooth
those proteins to be integrated into mitochondria or peroxisomes are synthesized in the
cytosol, then are directly taken to their organelles (do not go through rough ER)
those destined for secretion are syntheized
on rough ER (not like mitochondria and peroxisomes that the ribosomes go directly to)
is calmodulin a secondary messenger
no
hydrophilic messengers bind to receptors on the
PM
the cytosol has a higher concentration of ___ than ___ ions
potassium than sodium
the cell cytosol has a net __ charge
-
the cytoskeleton has 4 parts
microfilaments
IF
thick filaments
microtubules
microfilaments are made of
actin protein
what component of the cytoskeleton is used for anchoring and stabilization
microfilaments
what part of the cytoskeleton provides strength + stability and transports materials within the cytosol
IF
____ support the axons of nerves
neurofilaments (IF)
thick filaments are composed of
myosin protein
microtubules are made of
tubulin protein
what is the main component of the cytoskeleton
microtubules
what moves organelles inside the cell, change the shape of the cell, forms centrioles
microtubules
peroxisomes contain ___ to break down H2O2
catalase
paracrine
neighbouring
endocrine
through blood - long range
hormones are transported through the
blood
drugs with intracellular receptors are lipo___
philic
receptors in PM (3)
ion channel
enzyme, or directly activates an enzyme
GPLR
2 double layered organelles
mitochondria and nucleus
tyrosine kinases ___ proteins in the cell
phosphorylates
Gs stimulates
AC to convert ATP to cAMP
deactivation of alpha subunit occurs when
subunit hydrolyzes GTP to GDP
Gi
inhibits AC
cAMP activates
PKA
Gq results in
alpha subunit activating PLC which converts PIP2 to IP3 and DAG
IP3 moves to the cytosol and stimulates release of
Ca2+ from ER
DAG activates PKC which
phosphorylates proteins
increasng Ca2+ can cause
muscle contraction
secretion
Ca2+ as a 2nd messenger
binds to calmodulin - complex activates a protein kinase
cGMP is produced from _____ by _____
GTP
guanylate cyclases
cGMP activates
PKG
